We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2....We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2.55 GPa,Ⅲ-Ⅴ 7.67 GPa) and ZnTe(LPP-HPP Ⅰ 9.6 GPa,HPP Ⅰ-Ⅱ 12.0 GPa).As verification and application,sound velocity measurements on poly crystalline Al_(2)O_(3) to 12 GPa at room temperature were conducted and the ultrasonic result is in good agreement with previous reports.It demonstrates the feasibility of performing sound velocity measurements close to the mantle transition zone pressure condition in our laboratory.展开更多
A new heating method is proposed to increase the cell temperature of the 6-8 type multi-anvil apparatus without reducing the volume of the sample chamber. The double-layer heater assembly (DHA) has two layers of heate...A new heating method is proposed to increase the cell temperature of the 6-8 type multi-anvil apparatus without reducing the volume of the sample chamber. The double-layer heater assembly (DHA) has two layers of heaters connected in parallel. The temperature of the cell was able to reach 2500 ℃ by using 0.025 mm rhenium foils, and the temperature limit was increased by 25% compared with that of the traditional single-layer assembly. The power-temperature relationships for these two assemblies with different sizes were calibrated by using W/Re thermocouple at 20 GPa. When the volume of samples was the same, the DHA not only attained higher temperature, but also kept the holding time longer, compared to the traditional assembly. The results of more than ten experiments showed that the new 10/4 DHA with a relatively large sample size (2 mm in diameter and 4 mm in height) can work stably with the center temperature of the sample cavity exceeding 2300 ℃ under the pressure of 20 GPa.展开更多
Expansion of the pressure range of Kawai-type multi-anvil presses (KMAPs) with tungsten carbide (WC) anvils is called for, especially in the field of Earth science. However, no significant progress in pressure generat...Expansion of the pressure range of Kawai-type multi-anvil presses (KMAPs) with tungsten carbide (WC) anvils is called for, especially in the field of Earth science. However, no significant progress in pressure generation has been made for 40 years. Our recent studies have expanded the pressure generation of a KMAP with WC anvils to 65 GPa, which is the world record for high-pressure generation in this device and is more than 2.5 times higher than conventional pressure generation. We have also successfully generated pressures of about 50 GPa at high temperatures. This work reviews our recently developed technology for high-pressure generation. High-pressure generation at room temperature and at high temperature was attained by integration of the following techniques:① a precisely aligned guideblock system,② a high degree of hardness of the second-stage anvils,③ tapering of the second-stage anvil faces,④ a high-pressure cell consisting of materials with a high bulk modulus, and ⑤ high thermal insulation of the furnace. Our high-pressure technology will facilitate investigation of the phase stability and physical properties of materials under the conditions of the upper part of the lower mantle, and will permit the synthesis and characterization of novel materials.展开更多
Cell function has a tight relationship with cell architecture.Distribution of proteins to the correct compartment is one of the functions of the traffic pathway through the Golgi apparatus.The others are to ensure pro...Cell function has a tight relationship with cell architecture.Distribution of proteins to the correct compartment is one of the functions of the traffic pathway through the Golgi apparatus.The others are to ensure proper protein folding,the addition of post-translational modifications,and delivering to intracellular and extracellular destinations.Astrocytes are fundamental homeostatic cells,controlling multiple aspects of the central nervous system physiology,such as ion balance,nutrients,blood flow,neurotransmitters,and responses to insults.Astrocytes are polarized cells,and,such as neurons,extensively use the secretory pathway for secreting factors and exposing functional receptors,channels,and transporters on the plasma membrane.In this review,we will underline the importance of studying the Golgi apparatus and the secretory pathway in astrocytes,based on the possible tight connection between the Golgi apparatus and astrocytes’homeostatic function.Given the topic of this review,we will provide examples mostly about the Golgi apparatus structure,function,localization,and its involvement in astrocytes’homeostatic response,with an insight into congenital glycosylation disorders,as an example of a potential future field in the study of astrocyte homeostatic failure and Golgi apparatus alteration.展开更多
The Ilizarov apparatus was designed by its author 75 years ago and addresses a wide range of orthopedic conditions.Its classical assemblies are still self-sufficient and versatile.However,certain clinical scenarios re...The Ilizarov apparatus was designed by its author 75 years ago and addresses a wide range of orthopedic conditions.Its classical assemblies are still self-sufficient and versatile.However,certain clinical scenarios require a more specialized approach,and some groups of patients may benefit from customized Ilizarov constructs.Engineering science has designed various external fixators for orthopedic purposes,and some of those have become the gold standard for specific clinical tasks.We aimed to determine the current state and novel modifications of specialized external fixators for specific clinical situations which are based on the principles of the Ilizarov method.They are half-pin-based fixators for temporal fracture fixation,ring or hybrid devices for gradual deformity correction,and compression-distraction devices tailored for definite limb segments.Gradual correction of deformities can be achieved with external hexapods incorporating universal reduction units.Alternatively,external fixators with special connection mechanisms are able to provide independent movement of the rings in six degrees of freedom.Deformity correction can be performed with combined or sequential use of external and internal fixators.Special devices were developed for moving the split fragment for revascularization of the tibia.The units of external frames on the foot were modified to consider its complex anatomy and the clinical needs ranging from correction of multi-plane deformities,joint arthrodesis to distraction arthroplasty.Mini-fixators are compact external fixators for small bones of the hand and foot.The varieties of external fixators based on the Ilizarov principles have been designed to fulfill an ultimate goal of improving treatment outcomes.展开更多
The uniaxial compressive strength(UCS)of rocks is a vital geomechanical parameter widely used for rock mass classification,stability analysis,and engineering design in rock engineering.Various UCS testing methods and ...The uniaxial compressive strength(UCS)of rocks is a vital geomechanical parameter widely used for rock mass classification,stability analysis,and engineering design in rock engineering.Various UCS testing methods and apparatuses have been proposed over the past few decades.The objective of the present study is to summarize the status and development in theories,test apparatuses,data processing of the existing testing methods for UCS measurement.It starts with elaborating the theories of these test methods.Then the test apparatus and development trends for UCS measurement are summarized,followed by a discussion on rock specimens for test apparatus,and data processing methods.Next,the method selection for UCS measurement is recommended.It reveals that the rock failure mechanism in the UCS testing methods can be divided into compression-shear,compression-tension,composite failure mode,and no obvious failure mode.The trends of these apparatuses are towards automation,digitization,precision,and multi-modal test.Two size correction methods are commonly used.One is to develop empirical correlation between the measured indices and the specimen size.The other is to use a standard specimen to calculate the size correction factor.Three to five input parameters are commonly utilized in soft computation models to predict the UCS of rocks.The selection of the test methods for the UCS measurement can be carried out according to the testing scenario and the specimen size.The engineers can gain a comprehensive understanding of the UCS testing methods and its potential developments in various rock engineering endeavors.展开更多
Objectives:Triple-negative breast cancer(TNBC)presents a major treatment challenge due to its aggressive behavior.The dysfunction of the Golgi apparatus(GA)contributes to the development of various cancers.This study ...Objectives:Triple-negative breast cancer(TNBC)presents a major treatment challenge due to its aggressive behavior.The dysfunction of the Golgi apparatus(GA)contributes to the development of various cancers.This study aimed to utilize GA-related genes(GARGs)to forecast the prognosis and immune profile of TNBC.Methods:The data were downloaded from The Cancer Genome Atlas(TCGA)database,including 175 TNBC and 99 healthy samples.The differentially expressed GARGs(DEGARGs)were analyzed using the TCGA biolinks package.The patients with TNBC were classified into two clusters utilizing the ConsensusClusterPlus package according to prognosis-related DEGARGs,followed by comparing the differences in prognosis and immune infiltration between the two clusters.Next,LASSO and stepwise Cox regression were applied to establish a GARGs signature to forecast the TNBC prognosis.The association of the GARGs signature with immune infiltrates and drug sensitivity was further explored.Results:In total,430 DEGARGs were identified between TNBC and healthy samples,among which 20 were related to TNBC prognosis.Two GARG-related molecular clusters associated with different survival times and immune heterogeneity were identified.A risk model for TNBC was established based on six GARGs,and the high-risk(HR)group exhibited a poor prognosis.The HR group demonstrated a distinctly high M2 macrophage infiltration and low M1 macrophage infiltration,which contributed to an immunosuppressive tumor microenvironment and thus led to poor prognosis of the HR group.Immune dysfunction scores and programmed cell death ligand 1(PD-L1)expression were substantially elevated in the HR group.The HR group showed increased sensitivity to anticancer drugs,such as cisplatin.Conclusion:Our findings suggest that GARGs are involved in the pathogenesis of TNBC and provide new insights into prognostic prediction.The identified clusters and GARGs signatures have the potential to guide individualized therapy.展开更多
The structural and histochemical changes of the egg apparatus in the polyembryonic rice ( Oryza sativa L.), ApⅢ with the highest frequence of additional embryos among the polyembryonic rice investigated, before an...The structural and histochemical changes of the egg apparatus in the polyembryonic rice ( Oryza sativa L.), ApⅢ with the highest frequence of additional embryos among the polyembryonic rice investigated, before and after fertilization were studied and compared with those of normal and other polyembryonic rices in a similar developmental period. A total of 2 932 ovules were observed and each of them contained only a single embryo sac with a set of egg apparatus. Among 1 655 embryo sacs, there were 1 643 embryo sacs (99.27%) with one normal egg apparatus in each embryo sac, and only 12 embryo sacs (0.73%) from the remainder with 4_celled egg apparatus, i.e. two eggs and two synergids. Neither the numerous poly_egg apparatus and egg_like cells, nor the double set of embryo sacs each containing one egg apparatus and other abnormal egg apparatus in single ovary, which were reported by earlier investigators to have high frequency of embryo production in SB_1 and ApⅣ, were observed. The egg cell was located at the subterminal site of the micropylar end of embryo sac. The cytoplasm of egg cell was rich in protein materials and polysaccharide grains, which did not disappear until the division of zygote. The prominent nucleus was closely surrounded by protein and polysaccharide grains, which did not disappear until the division of zygote. No cytological difference was found between egg cells from the normal and abnormal egg apparatus. The two synergids were fully developed and situated at the upper most part of the micropylar end of the mature embryo sac. In most embryo sacs, the synergids were flask_shaped with longer necks, and a widened cap_shaped top, in close contact with the micropyle. The synergids had a well developed filiform apparatus. The characteristic appearance of the filiform apparatus as well as the cap_neck region of synergids before and after pollen tube penetration were easily distinguishable from the egg cell. The structure, the stainability with Coomassie Brilliant Blue and PAS reaction, the process of accumulation, distribution and disapperance of the cytoplasmic protein materials and polysaccharide grains of the two synergids, the persistent and rarely the receptive synergids before and after pollen tube penetration, were closely similar to those of egg cell of the same developmental stage. In comparison with normal and other polyembryonic rice reported, the size of nucleus and nucleolus and their stainability also strongly resembled those of egg cell. Based on the results observed, the main conclusions are summarized as follows: (1) the additional embryos very frequently developed in the young and mature seed of polyembryonic rice ApⅢ were produced by one or two synergids of normal egg apparatus, rarely by 4_celled egg apparatus; (2) during fertilization, the synergids, in addition to the natural specific function of introducing pollen tube and transferring sperms to egg cell and central cell, could be closely associated with the potentiality to breed one or two additional embryos; and (3) as compared with that of normal or other polyembryonic rice it is firstly disclosed that in a few embryo sacs of ApⅢ, the cytoplasmic and nuclear structure, the active anabolism and catabolism of protein and polysaccharide materials and the delayed disorganization at the mid_basal region of the receptive and persistent synergid still remained unchanged before the division of zygote. Such salient features could be the predisposition for the origin of additional embryos in ApⅢ.展开更多
Pressure allows the precise tuning of a fundamental parameter, the interatomic distance, which controls the electronic structure and virtually all interatomic interactions that determine material properties. Hence, pr...Pressure allows the precise tuning of a fundamental parameter, the interatomic distance, which controls the electronic structure and virtually all interatomic interactions that determine material properties. Hence, pressure tuning is an effective tool in the search for new materials with enhanced properties. To realize pressure tuning on matter, large-volume press (LVP) apparatuses have been widely used not only to synthesize novel materials but also to implement the in situ measurement of physical properties. Herein, we introduce the LVP apparatuses, including belt-type, cubic anvil, and 6-8 type multi-anvil, that will be constructed at the Synergetic Extreme Condition User Facility (SECUF) at Jilin University. Typically, cell volumes of 1000 mm3 can be obtained at 20 GPa in a belt-type apparatus that is significantly larger than that obtained in a 6-8 type multi-anvil apparatus at the same pressure. Furthermore, the in situ measurement of physical prop- erties, including thermological, electrical, and mechanical behaviors, is coupled to these LVP apparatuses. Some typical results of both synthetic experiments and in situ measurements obtained from the LVP apparatuses are also reviewed.展开更多
The present paper deals with stridulation apparatuses,observed by SEM,of 6 species of the genus Agromyza from China (2 species among them are newly recorded to China).Some morphological terms are proposed for the ...The present paper deals with stridulation apparatuses,observed by SEM,of 6 species of the genus Agromyza from China (2 species among them are newly recorded to China).Some morphological terms are proposed for the first time,and a key to 6 species of Agromyza applied by the characteristics of stridulatory file is given.We also scheme out a diagram showing relationship between two stridulatory file types.展开更多
An approach for studying the adsorption and desorption behaviors of single-stranded DNA( ssDNA) molecules on the mica surface by the surface forces apparatus( SFA) is reported,which can be used to characterize the...An approach for studying the adsorption and desorption behaviors of single-stranded DNA( ssDNA) molecules on the mica surface by the surface forces apparatus( SFA) is reported,which can be used to characterize the precise thickness,configuration and mechanical properties of ssDNA layers on the mica surface at a certain buffer solution. The formation of ss DNA layers is first studied by tuning the ssDNA concentrations, and the experimental results indicate that the ss DNA concentration of 100 ng / μL is ideal for forming a ssDNA monolayer structure on the mica surface, and the hardwall value measured to be 1.04 nm under this circumstance is regarded as the thickness of the ssDNA monolayer confined on mica. The desorption behavior of ssDNA molecules from the mica surface is further studied by observing and comparing different shapes of the force-distance curves under certain conditions. It is found that the desorption of ss DNA molecules from the mica surface occurs as the monovalent salts are added into the gap buffer. It is inferred that the competition effect between monovalent and divalent salts can induce the release of ssDNA from substrate.The results also reveal that 10 mmol / L monovalent salts( Na~+)is sufficient for the desorption of ssDNA from mica. This work provides an applicable method to study the binding mechanism of ss DNA molecules on inorganic substrates.展开更多
Almost all aspects of conodont research rely on a sound taxonomy based on comparative analysis.This is founded on hypotheses of homology which ultimately rest on knowledge of the location of elements in the apparatus....Almost all aspects of conodont research rely on a sound taxonomy based on comparative analysis.This is founded on hypotheses of homology which ultimately rest on knowledge of the location of elements in the apparatus.Natural assemblages—fossils that preserve the articulated remains of the conodont skeletal apparatus—provide our only direct evidence for element location,but very few are known from the Late Triassic.Here we describe fused clusters(natural assemblages)from the late Norian limestone beds of the Nanshuba Formation in Baoshan,Yunnan Province,southwestern China.Recurrent arrangements and juxtaposition of S and M elements in multiple clusters reveal the composition of the apparatus of Mockina and,probably,Parvigondolella.They indicate that these taxa had a standard 15 elements ozarkodinid apparatus,and provide new insights into the morphology of the elements occupying the P2,M and S locations of the apparatus.The apparatus comprised a single alate(hibbardelliform)S0 element,paired breviform digyrate(grodelliform)S1 and(enantiognathiform)S2 elements,paired bipennate(hindeodelliform)S3 and S4 elements,paired breviform digyrate(cypridodellifrom)M elements,paired,modified-angulate P2 elements(with reduced or lacking‘posterior’process)and segminiplanate(mockiniform and parvigondolelliform)P1 elements.Our results will allow testing of the hypothesis that Mockina,Parvigondolella and Misikella—critical taxa in Late Triassic biostratigraphy—are closely related and possessed morphologically similar elements in homologous locations.展开更多
The tried and tested multianvil apparatus has been widely used for high-pressure and hightemperature experimental studies in Earth science. As a result, many important results have been obtained for a better understan...The tried and tested multianvil apparatus has been widely used for high-pressure and hightemperature experimental studies in Earth science. As a result, many important results have been obtained for a better understanding of the components, structure and evolution of the Earth. Due to the strength limi- tation of materials, the attainable multianvil pressure is generally limited to about 30 GPa (corresponding to about 900 km of the depth in the Earth) when tungsten carbide cubes are adopted as second-stage anvils. Compared with tungsten carbide, the sintered diamond is a much harder material. The sintered diamond cubes were introduced as second-stage anvils in a 6--8 type multianvil apparatus in the 1980s, which largely enhanced the capacity of pressure generation in a large volume press. With the development of material synthesis and processing techniques, a large sintered diamond cube (14 ram) is now available. Recently, maximum attainable pressures reaching higher than 90 GPa (corresponding to about 2700 km of the depth in the Earth) have been generated at room temperature by adopting 14-mm sintered diamond anvils. Using this technique, a few researches have been carried out by the quenched method or combined with synchrotron radiation in situ observation. In this paper we review the properties of sintered diamond and the evolu- tion of pressure generation using sintered diamond anvils. As-yet unsolved problems and perspectives for uses in Earth Science are also discussed.展开更多
A precise and noninvasive method for the size and shape measurement of gold nanorods(GNRs) has been proposed based on depolarized dynamic light scattering(DDLS). A home-made DDLS apparatus has been established. By app...A precise and noninvasive method for the size and shape measurement of gold nanorods(GNRs) has been proposed based on depolarized dynamic light scattering(DDLS). A home-made DDLS apparatus has been established. By applying depolarized optical path with precise alignment method, the signal-to-noise ratio(SNR) of this apparatus is highly improved. GNRs with three different diameter and length has been precisely measured by using DDLS method as well as scanning electron microscopy(SEM). The thickness of adsorption layer of cetyltrimethylammonium bromide(CTAB) in solution has been taken into consideration. Results show that size measurement of GNRs by using DDLS method agrees very well with that by using SEM. In addition, it is shown that the extinction spectroscopy strongly limited the application of DDLS method by affecting the effective scattering light intensity. Proper laser wavelength should be chosen before the application of this method.展开更多
This paper reviews 19 apparatuses having highvelocity capabilities,describes a rotary-shear low to highvelocity friction apparatus installed at Institute of Geology,China Earthquake Administration,and reports results ...This paper reviews 19 apparatuses having highvelocity capabilities,describes a rotary-shear low to highvelocity friction apparatus installed at Institute of Geology,China Earthquake Administration,and reports results from velocity-jump tests on Pingxi fault gouge to illustrate technical problems in conducting velocity-stepping tests at high velocities.The apparatus is capable of producing plate to seismic velocities(44 mm/a to 2.1 m/s for specimens of 40 mm in diameter),using a 22 kW servomotor with a gear/belt system having three velocity ranges.A speed range can be changed by 103 or 106by using five electromagnetic clutches without stopping the motor.Two cam clutches allow fivefold velocity steps,and the motor speed can be increased from zero to 1,500 rpm in 0.1-0.2 s by changing the controlling voltage.A unique feature of the apparatus is a large specimen chamber where different specimen assemblies can be installed easily.In addition to a standard specimen assembly for friction experiments,two pressure vessels were made for pore pressures to 70 MPa;one at room temperature and the other at temperatures to 500 °C.Velocity step tests are needed to see if the framework of rate-and-state friction is applicable or not at high velocities.We report results from velocity jump tests from 1.4 mm/s to 1.4 m/s on yellowish gouge from a Pingxi fault zone,located at the northeastern part of the Longmenshan fault system that caused the 2008 Wenchuan earthquake.An instantaneous increase in friction followed by dramatic slip weakening was observed for the yellowish gouge with smooth sliding surfaces of host rock,but no instantaneous response was recognized for the same gouge with roughened sliding surfaces.Instantaneous and transient frictional properties upon velocity steps cannot be separated easily at high velocities,and technical improvements for velocity step tests are suggested.展开更多
The effects of acetylsalicylic acid (ASA), CaCl2, and ASA + CaCl2 on the photosynthetic apparatus and antioxidant enzyme activities were investigated in chrysanthemum Jinba (a cut flower cultivar) under low tempe...The effects of acetylsalicylic acid (ASA), CaCl2, and ASA + CaCl2 on the photosynthetic apparatus and antioxidant enzyme activities were investigated in chrysanthemum Jinba (a cut flower cultivar) under low temperature stress with low light (TL stress) (16/12℃, day/night, PFD 100 μmol m^-2 s-1). The results showed that under TL stress, the net photosynthesis rate (Pn), carboxylation efficiency (CE), apparent quantum yield (AQY), maximal photochemical efficiency (Fv/Fm) of PSII, quantum yield of PSII electron transport (ФPSII), and photochemical quenching (qP) of the chrysanthemum leaves in all treatments were significantly decreased, but the decreases were alleviated by ASA, CaCl2, and ASA + CaCl2 treatments compared with the controls. The alleviating effect of ASA + CaCI2 was better than either ASA or CaCl2 single treatment. Moreover, the ASA + CaCl2 treatment highly improved the chlorophyll content, relatively improved the number and size of chloroplast and starch grain in the leaves of chrysanthemum plants compared with ASA and CaCl2 treatments. It was indicated that ASA and/or CaCI2 could regulate the photosynthetic functions in the leaves of chrysanthemum plants to enhance the resistance against TL stress. On the other hand, reduction in relative conductance rate implied that ASA and/ or CaCl2 could protect from membrane injury in leaves of chrysanthemum plants. The activities of SOD, POD, and CAT in the treated leaves of chrysanthemum were increased as compared with the controls. It was suggested that ASA and/or CaCl2 had positive regulation effects on the defence enzyme activities in chrysanthemum leaves which could protect the photosynthetic apparatus to a certain degree under the TL stress. In brief, the treatment of ASA together with CaCl2 was better for chrysanthemum plants to adapt TL stress than single ASA or CaCl2 treatments.展开更多
Blood samples were harvested from the antecubital vein of 20 fasting patients with acute cerebral infarction at 1, 7 and 15 days after onset to prepare blood platelet suspension. Fasting antecubital vein blood was col...Blood samples were harvested from the antecubital vein of 20 fasting patients with acute cerebral infarction at 1, 7 and 15 days after onset to prepare blood platelet suspension. Fasting antecubital vein blood was collected from an additional 20 normal adults as controls. Under transmission elec- tron microscope, platelet Golgi tubules and vesicles became significantly thickened, enlarged, and irregular after acute cerebral infarction. Alpha granules in platelets significantly reduced in number, especially 1 day after cerebral infarction. Under immunoelectron microscopy, a few alpha granules aggregated around Golgi tubules and vesicles after infarction. These results suggested that platelet Golgi apparatus displayed significant morphological changes, which were possibly associated with enhanced synthetic and secretory functions of activated platelets after acute cerebral infarction. This study used Golgi apparatus blocking agent Brefeldin A to block Golgi apparatus in an aim to study the effects of Golgi apparatus on CD40L expression on the surface of activated platelets. Flow cytometry revealed that CD40L expression on activated platelet surfaces decreased significantly when Golgi apparatus was blocked, which indicated that Golgi apparatus participated in the syn- thesis and transport of CD40L to the platelet surface.展开更多
Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric...Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric field apparatus array group.The electric field component measurement model of the atmospheric electric field apparatus is established,and the orientation parameters of the thunderstorm point charge are defined.Based on the mirror method,the thunderstorm point charge coordinates are obtained by using the potential distribution formulas.To test the validity of the basic algorithm,the electric field component measurement error and the localization accuracy are studied.Besides the azimuth angle and the elevation angle,the localization parameters also include the distance from the apparatus to the thunderstorm cloud.Based on a primary electric field apparatus,we establish the array group of apparatuses.Based on this,the data measured by each apparatus is complementarily processed to regain the thunderstorm point charge position.The results show that,compared with the radar map data,this method can accurately reflect the location of the thunderstorm point charge,and has a better localization effect.Additionally,several observation results during thunderstorm weather have been presented.展开更多
Terpenes, aldehydes, ketones, benzene, and toluene are the important volatileorganic compounds (VOCs) emitted from wood composites. A sampling apparatus of VOCs for woodcomposites was designed and manufactured by Nort...Terpenes, aldehydes, ketones, benzene, and toluene are the important volatileorganic compounds (VOCs) emitted from wood composites. A sampling apparatus of VOCs for woodcomposites was designed and manufactured by Northeast Forestry University in China. Theconcentration of VOCs derived from wood based materials, such as flooring, panel wall, finishing,and furniture can be sampled in a small stainless steel chambers. A protocol is also developed inthis study to sample and measure the new and representative specimens. Preliminary research showedthat the properties of the equipment have good stability. The sort and the amount of differentcomponents can be detected from it. The apparatus is practicable.展开更多
The solidification process of metals plays a critical role in their final microstructure and, correspondingly, in their performance. It is therefore important to probe the solidification behavior of metals using advan...The solidification process of metals plays a critical role in their final microstructure and, correspondingly, in their performance. It is therefore important to probe the solidification behavior of metals using advanced in situ techniques. Synchrotron radiation X-ray imaging is one of the most powerful techniques to observe the solidification process of metals directly. Here, we review the development of the solidification apparatus, including the directional solidification device, resistance furnace, multi-field coupling device, semisolid forming device, aerodynamic levitation apparatus, and laser additive manufacturing apparatus. We highlight the recent research progress on the use of synchrotron radiation X-ray imaging to reveal the solidification behavior of metals in the above circumstances. The future perspectives of synchrotron radiation X-ray imaging in metal research are discussed. Further development of this technique will contribute to improve the understanding of the solidification process of metals and other types of materials at different scales.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.41873075the West Light Foundation of The Chinese Academy of Sciences。
文摘We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2.55 GPa,Ⅲ-Ⅴ 7.67 GPa) and ZnTe(LPP-HPP Ⅰ 9.6 GPa,HPP Ⅰ-Ⅱ 12.0 GPa).As verification and application,sound velocity measurements on poly crystalline Al_(2)O_(3) to 12 GPa at room temperature were conducted and the ultrasonic result is in good agreement with previous reports.It demonstrates the feasibility of performing sound velocity measurements close to the mantle transition zone pressure condition in our laboratory.
基金Project supported by the National Natural Science Foundation of China (Grant No. 51872189)the Fundamental Research Funds for the Central Universities, China (Grant No. 2018SCUH0022).
文摘A new heating method is proposed to increase the cell temperature of the 6-8 type multi-anvil apparatus without reducing the volume of the sample chamber. The double-layer heater assembly (DHA) has two layers of heaters connected in parallel. The temperature of the cell was able to reach 2500 ℃ by using 0.025 mm rhenium foils, and the temperature limit was increased by 25% compared with that of the traditional single-layer assembly. The power-temperature relationships for these two assemblies with different sizes were calibrated by using W/Re thermocouple at 20 GPa. When the volume of samples was the same, the DHA not only attained higher temperature, but also kept the holding time longer, compared to the traditional assembly. The results of more than ten experiments showed that the new 10/4 DHA with a relatively large sample size (2 mm in diameter and 4 mm in height) can work stably with the center temperature of the sample cavity exceeding 2300 ℃ under the pressure of 20 GPa.
基金supported by an Alexander von Humboldt Postdoctoral Fellowship to T.Ishiifunding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (787527)
文摘Expansion of the pressure range of Kawai-type multi-anvil presses (KMAPs) with tungsten carbide (WC) anvils is called for, especially in the field of Earth science. However, no significant progress in pressure generation has been made for 40 years. Our recent studies have expanded the pressure generation of a KMAP with WC anvils to 65 GPa, which is the world record for high-pressure generation in this device and is more than 2.5 times higher than conventional pressure generation. We have also successfully generated pressures of about 50 GPa at high temperatures. This work reviews our recently developed technology for high-pressure generation. High-pressure generation at room temperature and at high temperature was attained by integration of the following techniques:① a precisely aligned guideblock system,② a high degree of hardness of the second-stage anvils,③ tapering of the second-stage anvil faces,④ a high-pressure cell consisting of materials with a high bulk modulus, and ⑤ high thermal insulation of the furnace. Our high-pressure technology will facilitate investigation of the phase stability and physical properties of materials under the conditions of the upper part of the lower mantle, and will permit the synthesis and characterization of novel materials.
文摘Cell function has a tight relationship with cell architecture.Distribution of proteins to the correct compartment is one of the functions of the traffic pathway through the Golgi apparatus.The others are to ensure proper protein folding,the addition of post-translational modifications,and delivering to intracellular and extracellular destinations.Astrocytes are fundamental homeostatic cells,controlling multiple aspects of the central nervous system physiology,such as ion balance,nutrients,blood flow,neurotransmitters,and responses to insults.Astrocytes are polarized cells,and,such as neurons,extensively use the secretory pathway for secreting factors and exposing functional receptors,channels,and transporters on the plasma membrane.In this review,we will underline the importance of studying the Golgi apparatus and the secretory pathway in astrocytes,based on the possible tight connection between the Golgi apparatus and astrocytes’homeostatic function.Given the topic of this review,we will provide examples mostly about the Golgi apparatus structure,function,localization,and its involvement in astrocytes’homeostatic response,with an insight into congenital glycosylation disorders,as an example of a potential future field in the study of astrocyte homeostatic failure and Golgi apparatus alteration.
文摘The Ilizarov apparatus was designed by its author 75 years ago and addresses a wide range of orthopedic conditions.Its classical assemblies are still self-sufficient and versatile.However,certain clinical scenarios require a more specialized approach,and some groups of patients may benefit from customized Ilizarov constructs.Engineering science has designed various external fixators for orthopedic purposes,and some of those have become the gold standard for specific clinical tasks.We aimed to determine the current state and novel modifications of specialized external fixators for specific clinical situations which are based on the principles of the Ilizarov method.They are half-pin-based fixators for temporal fracture fixation,ring or hybrid devices for gradual deformity correction,and compression-distraction devices tailored for definite limb segments.Gradual correction of deformities can be achieved with external hexapods incorporating universal reduction units.Alternatively,external fixators with special connection mechanisms are able to provide independent movement of the rings in six degrees of freedom.Deformity correction can be performed with combined or sequential use of external and internal fixators.Special devices were developed for moving the split fragment for revascularization of the tibia.The units of external frames on the foot were modified to consider its complex anatomy and the clinical needs ranging from correction of multi-plane deformities,joint arthrodesis to distraction arthroplasty.Mini-fixators are compact external fixators for small bones of the hand and foot.The varieties of external fixators based on the Ilizarov principles have been designed to fulfill an ultimate goal of improving treatment outcomes.
基金the National Natural Science Foundation of China(Grant Nos.52308403 and 52079068)the Yunlong Lake Laboratory of Deep Underground Science and Engineering(No.104023005)the China Postdoctoral Science Foundation(Grant No.2023M731998)for funding provided to this work.
文摘The uniaxial compressive strength(UCS)of rocks is a vital geomechanical parameter widely used for rock mass classification,stability analysis,and engineering design in rock engineering.Various UCS testing methods and apparatuses have been proposed over the past few decades.The objective of the present study is to summarize the status and development in theories,test apparatuses,data processing of the existing testing methods for UCS measurement.It starts with elaborating the theories of these test methods.Then the test apparatus and development trends for UCS measurement are summarized,followed by a discussion on rock specimens for test apparatus,and data processing methods.Next,the method selection for UCS measurement is recommended.It reveals that the rock failure mechanism in the UCS testing methods can be divided into compression-shear,compression-tension,composite failure mode,and no obvious failure mode.The trends of these apparatuses are towards automation,digitization,precision,and multi-modal test.Two size correction methods are commonly used.One is to develop empirical correlation between the measured indices and the specimen size.The other is to use a standard specimen to calculate the size correction factor.Three to five input parameters are commonly utilized in soft computation models to predict the UCS of rocks.The selection of the test methods for the UCS measurement can be carried out according to the testing scenario and the specimen size.The engineers can gain a comprehensive understanding of the UCS testing methods and its potential developments in various rock engineering endeavors.
文摘Objectives:Triple-negative breast cancer(TNBC)presents a major treatment challenge due to its aggressive behavior.The dysfunction of the Golgi apparatus(GA)contributes to the development of various cancers.This study aimed to utilize GA-related genes(GARGs)to forecast the prognosis and immune profile of TNBC.Methods:The data were downloaded from The Cancer Genome Atlas(TCGA)database,including 175 TNBC and 99 healthy samples.The differentially expressed GARGs(DEGARGs)were analyzed using the TCGA biolinks package.The patients with TNBC were classified into two clusters utilizing the ConsensusClusterPlus package according to prognosis-related DEGARGs,followed by comparing the differences in prognosis and immune infiltration between the two clusters.Next,LASSO and stepwise Cox regression were applied to establish a GARGs signature to forecast the TNBC prognosis.The association of the GARGs signature with immune infiltrates and drug sensitivity was further explored.Results:In total,430 DEGARGs were identified between TNBC and healthy samples,among which 20 were related to TNBC prognosis.Two GARG-related molecular clusters associated with different survival times and immune heterogeneity were identified.A risk model for TNBC was established based on six GARGs,and the high-risk(HR)group exhibited a poor prognosis.The HR group demonstrated a distinctly high M2 macrophage infiltration and low M1 macrophage infiltration,which contributed to an immunosuppressive tumor microenvironment and thus led to poor prognosis of the HR group.Immune dysfunction scores and programmed cell death ligand 1(PD-L1)expression were substantially elevated in the HR group.The HR group showed increased sensitivity to anticancer drugs,such as cisplatin.Conclusion:Our findings suggest that GARGs are involved in the pathogenesis of TNBC and provide new insights into prognostic prediction.The identified clusters and GARGs signatures have the potential to guide individualized therapy.
文摘The structural and histochemical changes of the egg apparatus in the polyembryonic rice ( Oryza sativa L.), ApⅢ with the highest frequence of additional embryos among the polyembryonic rice investigated, before and after fertilization were studied and compared with those of normal and other polyembryonic rices in a similar developmental period. A total of 2 932 ovules were observed and each of them contained only a single embryo sac with a set of egg apparatus. Among 1 655 embryo sacs, there were 1 643 embryo sacs (99.27%) with one normal egg apparatus in each embryo sac, and only 12 embryo sacs (0.73%) from the remainder with 4_celled egg apparatus, i.e. two eggs and two synergids. Neither the numerous poly_egg apparatus and egg_like cells, nor the double set of embryo sacs each containing one egg apparatus and other abnormal egg apparatus in single ovary, which were reported by earlier investigators to have high frequency of embryo production in SB_1 and ApⅣ, were observed. The egg cell was located at the subterminal site of the micropylar end of embryo sac. The cytoplasm of egg cell was rich in protein materials and polysaccharide grains, which did not disappear until the division of zygote. The prominent nucleus was closely surrounded by protein and polysaccharide grains, which did not disappear until the division of zygote. No cytological difference was found between egg cells from the normal and abnormal egg apparatus. The two synergids were fully developed and situated at the upper most part of the micropylar end of the mature embryo sac. In most embryo sacs, the synergids were flask_shaped with longer necks, and a widened cap_shaped top, in close contact with the micropyle. The synergids had a well developed filiform apparatus. The characteristic appearance of the filiform apparatus as well as the cap_neck region of synergids before and after pollen tube penetration were easily distinguishable from the egg cell. The structure, the stainability with Coomassie Brilliant Blue and PAS reaction, the process of accumulation, distribution and disapperance of the cytoplasmic protein materials and polysaccharide grains of the two synergids, the persistent and rarely the receptive synergids before and after pollen tube penetration, were closely similar to those of egg cell of the same developmental stage. In comparison with normal and other polyembryonic rice reported, the size of nucleus and nucleolus and their stainability also strongly resembled those of egg cell. Based on the results observed, the main conclusions are summarized as follows: (1) the additional embryos very frequently developed in the young and mature seed of polyembryonic rice ApⅢ were produced by one or two synergids of normal egg apparatus, rarely by 4_celled egg apparatus; (2) during fertilization, the synergids, in addition to the natural specific function of introducing pollen tube and transferring sperms to egg cell and central cell, could be closely associated with the potentiality to breed one or two additional embryos; and (3) as compared with that of normal or other polyembryonic rice it is firstly disclosed that in a few embryo sacs of ApⅢ, the cytoplasmic and nuclear structure, the active anabolism and catabolism of protein and polysaccharide materials and the delayed disorganization at the mid_basal region of the receptive and persistent synergid still remained unchanged before the division of zygote. Such salient features could be the predisposition for the origin of additional embryos in ApⅢ.
文摘Pressure allows the precise tuning of a fundamental parameter, the interatomic distance, which controls the electronic structure and virtually all interatomic interactions that determine material properties. Hence, pressure tuning is an effective tool in the search for new materials with enhanced properties. To realize pressure tuning on matter, large-volume press (LVP) apparatuses have been widely used not only to synthesize novel materials but also to implement the in situ measurement of physical properties. Herein, we introduce the LVP apparatuses, including belt-type, cubic anvil, and 6-8 type multi-anvil, that will be constructed at the Synergetic Extreme Condition User Facility (SECUF) at Jilin University. Typically, cell volumes of 1000 mm3 can be obtained at 20 GPa in a belt-type apparatus that is significantly larger than that obtained in a 6-8 type multi-anvil apparatus at the same pressure. Furthermore, the in situ measurement of physical prop- erties, including thermological, electrical, and mechanical behaviors, is coupled to these LVP apparatuses. Some typical results of both synthetic experiments and in situ measurements obtained from the LVP apparatuses are also reviewed.
文摘The present paper deals with stridulation apparatuses,observed by SEM,of 6 species of the genus Agromyza from China (2 species among them are newly recorded to China).Some morphological terms are proposed for the first time,and a key to 6 species of Agromyza applied by the characteristics of stridulatory file is given.We also scheme out a diagram showing relationship between two stridulatory file types.
基金The National Basic Research Program of China(973Program)(No.2011CB707605)the Fundamental Research Funds for the Central Universities(No.2242015K42085)+1 种基金the Scientific Innovation Research of College Graduates in Jiangsu Province(No.KYLX-0100)the Research Start-Up Fund of Southeast University
文摘An approach for studying the adsorption and desorption behaviors of single-stranded DNA( ssDNA) molecules on the mica surface by the surface forces apparatus( SFA) is reported,which can be used to characterize the precise thickness,configuration and mechanical properties of ssDNA layers on the mica surface at a certain buffer solution. The formation of ss DNA layers is first studied by tuning the ssDNA concentrations, and the experimental results indicate that the ss DNA concentration of 100 ng / μL is ideal for forming a ssDNA monolayer structure on the mica surface, and the hardwall value measured to be 1.04 nm under this circumstance is regarded as the thickness of the ssDNA monolayer confined on mica. The desorption behavior of ssDNA molecules from the mica surface is further studied by observing and comparing different shapes of the force-distance curves under certain conditions. It is found that the desorption of ss DNA molecules from the mica surface occurs as the monovalent salts are added into the gap buffer. It is inferred that the competition effect between monovalent and divalent salts can induce the release of ssDNA from substrate.The results also reveal that 10 mmol / L monovalent salts( Na~+)is sufficient for the desorption of ssDNA from mica. This work provides an applicable method to study the binding mechanism of ss DNA molecules on inorganic substrates.
基金supported by the National Natural Sciences Foundation of China(Nos.41830320,41972033,41572324)。
文摘Almost all aspects of conodont research rely on a sound taxonomy based on comparative analysis.This is founded on hypotheses of homology which ultimately rest on knowledge of the location of elements in the apparatus.Natural assemblages—fossils that preserve the articulated remains of the conodont skeletal apparatus—provide our only direct evidence for element location,but very few are known from the Late Triassic.Here we describe fused clusters(natural assemblages)from the late Norian limestone beds of the Nanshuba Formation in Baoshan,Yunnan Province,southwestern China.Recurrent arrangements and juxtaposition of S and M elements in multiple clusters reveal the composition of the apparatus of Mockina and,probably,Parvigondolella.They indicate that these taxa had a standard 15 elements ozarkodinid apparatus,and provide new insights into the morphology of the elements occupying the P2,M and S locations of the apparatus.The apparatus comprised a single alate(hibbardelliform)S0 element,paired breviform digyrate(grodelliform)S1 and(enantiognathiform)S2 elements,paired bipennate(hindeodelliform)S3 and S4 elements,paired breviform digyrate(cypridodellifrom)M elements,paired,modified-angulate P2 elements(with reduced or lacking‘posterior’process)and segminiplanate(mockiniform and parvigondolelliform)P1 elements.Our results will allow testing of the hypothesis that Mockina,Parvigondolella and Misikella—critical taxa in Late Triassic biostratigraphy—are closely related and possessed morphologically similar elements in homologous locations.
基金supported by National Natural Science Foundation of China(Grant Nos.40973045 and 41010104017)
文摘The tried and tested multianvil apparatus has been widely used for high-pressure and hightemperature experimental studies in Earth science. As a result, many important results have been obtained for a better understanding of the components, structure and evolution of the Earth. Due to the strength limi- tation of materials, the attainable multianvil pressure is generally limited to about 30 GPa (corresponding to about 900 km of the depth in the Earth) when tungsten carbide cubes are adopted as second-stage anvils. Compared with tungsten carbide, the sintered diamond is a much harder material. The sintered diamond cubes were introduced as second-stage anvils in a 6--8 type multianvil apparatus in the 1980s, which largely enhanced the capacity of pressure generation in a large volume press. With the development of material synthesis and processing techniques, a large sintered diamond cube (14 ram) is now available. Recently, maximum attainable pressures reaching higher than 90 GPa (corresponding to about 2700 km of the depth in the Earth) have been generated at room temperature by adopting 14-mm sintered diamond anvils. Using this technique, a few researches have been carried out by the quenched method or combined with synchrotron radiation in situ observation. In this paper we review the properties of sintered diamond and the evolu- tion of pressure generation using sintered diamond anvils. As-yet unsolved problems and perspectives for uses in Earth Science are also discussed.
基金This work has been supported by the National Natural Science Foundation of China(No.51805505)the Key R&D Projects of Science and Technology(No.2016YFA0200901)the Basic Science Research Operating Fund of NIM(No.AKY 1817)。
文摘A precise and noninvasive method for the size and shape measurement of gold nanorods(GNRs) has been proposed based on depolarized dynamic light scattering(DDLS). A home-made DDLS apparatus has been established. By applying depolarized optical path with precise alignment method, the signal-to-noise ratio(SNR) of this apparatus is highly improved. GNRs with three different diameter and length has been precisely measured by using DDLS method as well as scanning electron microscopy(SEM). The thickness of adsorption layer of cetyltrimethylammonium bromide(CTAB) in solution has been taken into consideration. Results show that size measurement of GNRs by using DDLS method agrees very well with that by using SEM. In addition, it is shown that the extinction spectroscopy strongly limited the application of DDLS method by affecting the effective scattering light intensity. Proper laser wavelength should be chosen before the application of this method.
基金supported by State Key Laboratory of Earthquake Dynamics (Project No.LED2014A06 & LED2010A05)
文摘This paper reviews 19 apparatuses having highvelocity capabilities,describes a rotary-shear low to highvelocity friction apparatus installed at Institute of Geology,China Earthquake Administration,and reports results from velocity-jump tests on Pingxi fault gouge to illustrate technical problems in conducting velocity-stepping tests at high velocities.The apparatus is capable of producing plate to seismic velocities(44 mm/a to 2.1 m/s for specimens of 40 mm in diameter),using a 22 kW servomotor with a gear/belt system having three velocity ranges.A speed range can be changed by 103 or 106by using five electromagnetic clutches without stopping the motor.Two cam clutches allow fivefold velocity steps,and the motor speed can be increased from zero to 1,500 rpm in 0.1-0.2 s by changing the controlling voltage.A unique feature of the apparatus is a large specimen chamber where different specimen assemblies can be installed easily.In addition to a standard specimen assembly for friction experiments,two pressure vessels were made for pore pressures to 70 MPa;one at room temperature and the other at temperatures to 500 °C.Velocity step tests are needed to see if the framework of rate-and-state friction is applicable or not at high velocities.We report results from velocity jump tests from 1.4 mm/s to 1.4 m/s on yellowish gouge from a Pingxi fault zone,located at the northeastern part of the Longmenshan fault system that caused the 2008 Wenchuan earthquake.An instantaneous increase in friction followed by dramatic slip weakening was observed for the yellowish gouge with smooth sliding surfaces of host rock,but no instantaneous response was recognized for the same gouge with roughened sliding surfaces.Instantaneous and transient frictional properties upon velocity steps cannot be separated easily at high velocities,and technical improvements for velocity step tests are suggested.
基金supported by the National Key Tech-nologies R&D Program of China during the 11th Five-Year-Plan period (2006BAD10B07)the Project for Returned Overseas Atudents to Start Research from Ministry of Education,China (33206)
文摘The effects of acetylsalicylic acid (ASA), CaCl2, and ASA + CaCl2 on the photosynthetic apparatus and antioxidant enzyme activities were investigated in chrysanthemum Jinba (a cut flower cultivar) under low temperature stress with low light (TL stress) (16/12℃, day/night, PFD 100 μmol m^-2 s-1). The results showed that under TL stress, the net photosynthesis rate (Pn), carboxylation efficiency (CE), apparent quantum yield (AQY), maximal photochemical efficiency (Fv/Fm) of PSII, quantum yield of PSII electron transport (ФPSII), and photochemical quenching (qP) of the chrysanthemum leaves in all treatments were significantly decreased, but the decreases were alleviated by ASA, CaCl2, and ASA + CaCl2 treatments compared with the controls. The alleviating effect of ASA + CaCI2 was better than either ASA or CaCl2 single treatment. Moreover, the ASA + CaCl2 treatment highly improved the chlorophyll content, relatively improved the number and size of chloroplast and starch grain in the leaves of chrysanthemum plants compared with ASA and CaCl2 treatments. It was indicated that ASA and/or CaCI2 could regulate the photosynthetic functions in the leaves of chrysanthemum plants to enhance the resistance against TL stress. On the other hand, reduction in relative conductance rate implied that ASA and/ or CaCl2 could protect from membrane injury in leaves of chrysanthemum plants. The activities of SOD, POD, and CAT in the treated leaves of chrysanthemum were increased as compared with the controls. It was suggested that ASA and/or CaCl2 had positive regulation effects on the defence enzyme activities in chrysanthemum leaves which could protect the photosynthetic apparatus to a certain degree under the TL stress. In brief, the treatment of ASA together with CaCl2 was better for chrysanthemum plants to adapt TL stress than single ASA or CaCl2 treatments.
基金supported by grants from the National Natural Science Foundation of China, No.81171239/H0914Frontier Research Key Project,Central South University in China (2010-2011), No.2177-721500065the Education Expenditure of Hunan Provincial Finance Department in China, No.2010163
文摘Blood samples were harvested from the antecubital vein of 20 fasting patients with acute cerebral infarction at 1, 7 and 15 days after onset to prepare blood platelet suspension. Fasting antecubital vein blood was collected from an additional 20 normal adults as controls. Under transmission elec- tron microscope, platelet Golgi tubules and vesicles became significantly thickened, enlarged, and irregular after acute cerebral infarction. Alpha granules in platelets significantly reduced in number, especially 1 day after cerebral infarction. Under immunoelectron microscopy, a few alpha granules aggregated around Golgi tubules and vesicles after infarction. These results suggested that platelet Golgi apparatus displayed significant morphological changes, which were possibly associated with enhanced synthetic and secretory functions of activated platelets after acute cerebral infarction. This study used Golgi apparatus blocking agent Brefeldin A to block Golgi apparatus in an aim to study the effects of Golgi apparatus on CD40L expression on the surface of activated platelets. Flow cytometry revealed that CD40L expression on activated platelet surfaces decreased significantly when Golgi apparatus was blocked, which indicated that Golgi apparatus participated in the syn- thesis and transport of CD40L to the platelet surface.
基金This work is supported by the National Key Research and Development Program of China(Grant No.2021YFE0105500)the National Natural Science Foundation of China(Grant No.61671248)+2 种基金the Key Research and Development Plan of Jiangsu Province,China(Grant No.BE2018719)Postgraduate Research and Practice Innovation Program of Jiangsu Province(Grant No.SJCX19_0309)the Advantage Discipline Information and Communication Engineering of Jiangsu Province,China.
文摘Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric field apparatus array group.The electric field component measurement model of the atmospheric electric field apparatus is established,and the orientation parameters of the thunderstorm point charge are defined.Based on the mirror method,the thunderstorm point charge coordinates are obtained by using the potential distribution formulas.To test the validity of the basic algorithm,the electric field component measurement error and the localization accuracy are studied.Besides the azimuth angle and the elevation angle,the localization parameters also include the distance from the apparatus to the thunderstorm cloud.Based on a primary electric field apparatus,we establish the array group of apparatuses.Based on this,the data measured by each apparatus is complementarily processed to regain the thunderstorm point charge position.The results show that,compared with the radar map data,this method can accurately reflect the location of the thunderstorm point charge,and has a better localization effect.Additionally,several observation results during thunderstorm weather have been presented.
基金This project is supported by the grand of the Oversea Back Scholar Research Startup of China Education Ministry, Heilongjiang Post-doctorial Research Startup and NEFU Creative Item.
文摘Terpenes, aldehydes, ketones, benzene, and toluene are the important volatileorganic compounds (VOCs) emitted from wood composites. A sampling apparatus of VOCs for woodcomposites was designed and manufactured by Northeast Forestry University in China. Theconcentration of VOCs derived from wood based materials, such as flooring, panel wall, finishing,and furniture can be sampled in a small stainless steel chambers. A protocol is also developed inthis study to sample and measure the new and representative specimens. Preliminary research showedthat the properties of the equipment have good stability. The sort and the amount of differentcomponents can be detected from it. The apparatus is practicable.
基金supported by the National Natural Science Foundation of China for Excellent Young Scholars(No.51922068)the National Natural Science Foundation of China(Nos.51821001,51904186)the fund of the State Key Laboratory of Solidification Processing in NWPU,China(No.SKLSP202102)。
文摘The solidification process of metals plays a critical role in their final microstructure and, correspondingly, in their performance. It is therefore important to probe the solidification behavior of metals using advanced in situ techniques. Synchrotron radiation X-ray imaging is one of the most powerful techniques to observe the solidification process of metals directly. Here, we review the development of the solidification apparatus, including the directional solidification device, resistance furnace, multi-field coupling device, semisolid forming device, aerodynamic levitation apparatus, and laser additive manufacturing apparatus. We highlight the recent research progress on the use of synchrotron radiation X-ray imaging to reveal the solidification behavior of metals in the above circumstances. The future perspectives of synchrotron radiation X-ray imaging in metal research are discussed. Further development of this technique will contribute to improve the understanding of the solidification process of metals and other types of materials at different scales.