Ultrahigh pressure generation at high temperatures is technologically challenging for large sample volumes.In this study,we successfully generated pressures of 37.3-40.4 GPa at 1900-2100 K in a Walker-type large-volum...Ultrahigh pressure generation at high temperatures is technologically challenging for large sample volumes.In this study,we successfully generated pressures of 37.3-40.4 GPa at 1900-2100 K in a Walker-type large-volume press(LVP).Expansion of the pressure range at high temperatures was achieved by adapting newly designed ZK01F tungsten carbide(WC)anvils with tapered surfaces and using cell assemblies with an^(-1) mm^(3) sample volume and hard materials,as well as by applying certain adjustments to the apparatus.The pressure efficiencies of the different types of WC anvils and cell assemblies were also studied.Using the above-mentioned techniques,we successfully synthesized and characterized bulk samples of nearly pure sp3-hybridized ultrahard amorphous carbon,core-shell nanocrystals with high Néel temperatures,as well as large-sized single crystals of lower-mantle minerals.The developed LVP techniques presented here could enable the exploration of the chemical and physical properties of novel materials and Earth’s interior.展开更多
Tight gas reservoirs are often characterized by pronounced heterogeneity and poor continuity,resulting in wide variability in production enhancement and net present value(NPV)for different geological parameter combina...Tight gas reservoirs are often characterized by pronounced heterogeneity and poor continuity,resulting in wide variability in production enhancement and net present value(NPV)for different geological parameter combinations(see e.g.,the Ordos Basin).The conditions governing geological adaptability remain insufficiently defined.To address these challenges,this study integrates large-volume hydraulic fracturing,numerical production simulation,and economic evaluation to elucidate the mechanisms by which large-scale fracturing enhances fracture parameters in tight gas formations.The analysis reveals that,for identical proppant and fluid volumes,increasing the fracturing injection rate leads to longer and taller fractures.Over the same production period,this results in a more rapid decline in average reservoir pressure and a higher cumulative gas output.Through simulations conducted at varying injection rates across 11 production wells in the target block,the study demonstrates that large-volume fracturing can effectively connect otherwise isolated tight gas pockets,enlarge the drainage area,and substantially boost individual well production.A comparative assessment of simulation outcomes and economic performance shows that large-volume fracturing significantly improves gas recovery and NPV compared to conventional smaller-scale treatments.The study identifies the key geological indicators that influence differences in production enhancement and economic returns between small-and large-volume fracturing strategies.Based on these findings,a decision matrix is developed(utilizing a trapezoidal membership function)to evaluate the geological suitability of large-volume fracturing in tight gas reservoirs.This matrix is applied to the 11 target wells,with the evaluation results aligning well with those obtained from numerical simulations.展开更多
Deformation can change the transition pathway of materials under high pressure,thus significantly affects physical and chemical properties of matters.However,accurate pressure calibration under deformation is challeng...Deformation can change the transition pathway of materials under high pressure,thus significantly affects physical and chemical properties of matters.However,accurate pressure calibration under deformation is challenging and thereby causes relatively large pressure uncertainties in deformation experiments,resulting in the synthesis of complex multiphase materials.Here,pressure generations of three types of deformation assemblies were well calibrated in a Walker-type largevolume press(LVP)by electrical resistance measurements combined with finite element simulations(FESs).Hard Al_(2)O_(3) or diamond pistons in shear and uniaxial deformation assemblies significantly increase the efficiency of pressure generation compared with the conventional quasi-hydrostatic assembly.The uniaxial deformation assembly using flat diamond pistons possesses the highest efficiency in these deformation assemblies.This finding is further confirmed by stress distribution analysis based on FESs.With this deformation assembly,we found shear can effectively promote the transformation of C60 into diamond under high pressure and realized the synthesis of phase-pure diamond at relatively moderate pressure and temperature conditions.The present developed techniques will help improve pressure efficiencies in LVP and explore the new physical and chemical properties of materials under deformation in both science and technology.展开更多
Neutron diffraction techniques of large-volume samples at high pressure using compact opposed-anvil cells are developed at a reactor neutron source, China＇s Mianyang research reactor. We achieve a high-pressure condi...Neutron diffraction techniques of large-volume samples at high pressure using compact opposed-anvil cells are developed at a reactor neutron source, China＇s Mianyang research reactor. We achieve a high-pressure condition of in situ neutron diffraction by means of a newly designed large-volume opposed-anvil cell. This pressure calibration is based on resistance measurements of bismuth and the neutron diffraction of iron. Pressure calibration experiments are performed at room temperature for a new cell using the tungsten carbide anvils with a tapered angle of 30°, Φ4.5 mm culet diameter and the metal-nonmetal composite gasket with a thickness of 2 mm. Transitions in Bi（Ⅰ–Ⅱ 2.55 GPa, Ⅱ–V 7.7 GPa） are observed at 100 and 300 kN, respectively, by resistance measurements.The pressure measurement results of neutron diffraction are consistent with resistance measurements of bismuth.As a result, pressures up to about 7.7 GPa can routinely and stably be achieved using this apparatus, with the sample volume of 9 mm^3.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 paper shows selected aspects of the microclimate change inside the selected type of the large-volume buildings--sacral buildings and for comparison--in the residential apartment buildings, caused by the heat emitt...The paper shows selected aspects of the microclimate change inside the selected type of the large-volume buildings--sacral buildings and for comparison--in the residential apartment buildings, caused by the heat emitted by people. Microclimate parameters such as air temperature or air relative humidity change because of heat emission from people staying inside there. Exemplary methods and results of research conducted in the existing sacral buildings and in the residential apartment buildings are shown. It is based on author＇s research, whose novelty is the research of the human heat emission in case of a big number of people staying inside a large-volume building. It can be useful for sacral buildings and other large-volume buildings design and for a microclimate shaping. In some large-volume buildings as the sacral buildings with a big number of people staying inside at the same time heat emitted from people significantly influences on a microclimate. Human heat streams can be useful as a part of the heat balance of the room.展开更多
A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith p...A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass spectrometry.Thewater samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction plates.The method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface water.For a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most analytes.For the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for mostanalytes.The new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other chemicals.As a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water.展开更多
For cirrhotic refractory ascites,diuretics combined with albumin and vasoactive drugs are the first-line choice for ascites management.However,their therapeutic effects are limited,and most refractory ascites do not r...For cirrhotic refractory ascites,diuretics combined with albumin and vasoactive drugs are the first-line choice for ascites management.However,their therapeutic effects are limited,and most refractory ascites do not respond to medication treat-ment,necessitating consideration of drainage or surgical interventions.Con-sequently,numerous drainage methods for cirrhotic ascites have emerged,including large-volume paracentesis,transjugular intrahepatic portosystemic shunt,peritoneovenous shunt,automated low-flow ascites pump,cell-free and concentrated ascites reinfusion therapy,and peritoneal catheter drainage.This review introduces the advantages and disadvantages of these methods in different aspects,as well as indications and contraindications for this disease.展开更多
To provide an overview of the properties of human serum albumin(HSA), and to review the evidence for the use of human albumin solution(HAS) in critical illness, sepsis and cirrhosis. A MEDLINE search was performed usi...To provide an overview of the properties of human serum albumin(HSA), and to review the evidence for the use of human albumin solution(HAS) in critical illness, sepsis and cirrhosis. A MEDLINE search was performed using the terms "human albumin", "critical illness", "sepsis" and "cirrhosis". The references of retrieved articles were reviewed manually. Studies published between 1980 and 2014 were selected based on quality criteria. Data extraction was performed by all authors. HSA is the main plasma protein contributing greatly to its oncotic pressure. HSA demonstrates important binding properties for endogenous and exogenous toxins, drugs and drug metabolites that account for its anti-oxidant and anti-inflammatory properties. In disease states, hypoalbuminaemia is secondary to decreased HSA production, increased loss or transcapillary leakage into the interstitial space. HSA function can be also altered in disease with reduced albumin binding capacity and increased production of modified isoforms. HAS has been used as volume expander in critical illness, but received criticism due to cost and concerns regarding safety. More recent studies confirmed the safety of HAS, but failed to show any survival benefit compared to the cheaper crystalloid fluids, therefore limiting its use. On the contrary, in cirrhosis there is robust data to support the efficacy of HAS for the prevention of circulatory dysfunction post-large volume paracentesis and in the context of spontaneous bacterial peritonitis, and for the treatment of hepato-renal syndrome and hypervolaemic hyponatraemia. It is likely that not only the oncotic properties of HAS are beneficial in cirrhosis, but also its functional properties, as HAS replaces the dysfunctional HSA. The role of HAS as the resuscitation fluid of choice in critically ill patients with cirrhosis, beyond the established indications for HAS use, should be addressed in future studies.展开更多
In this paper,a three-dimensional non-equilibrium steady arc model is used to investigate the temperature,velocity and electromagnetic field in multi-cathode arc torch,and the formation mechanism of a large-area,unifo...In this paper,a three-dimensional non-equilibrium steady arc model is used to investigate the temperature,velocity and electromagnetic field in multi-cathode arc torch,and the formation mechanism of a large-area,uniform and diffused arc plasma is analyzed.The numerical simulation results show that a large volume plasma region can be formed in the central region of the generator during discharge.During this process,the maximum electron temperature appears near the cathode and in the central convergence region,while the maximum heavy particle temperature only appears in the central convergence region.This phenomenon is consistent with the experimental arc images.Near the cathode tip,the arc column is in a contraction state.In the area slightly away from the cathode,the six arc columns begin to join together.In the plasma generator,there is a large-scale current distribution in all directions of X,Y and Z,forming a stable arc plasma with a wide range of diffusion.The calculated electron temperature distribution is in good agreement with the measured electron temperature.The results suggest that the largearea diffused arc plasma in the multi-cathode arc torch is the combined effect of current distribution,convection heat transfer and heat conduction.展开更多
The Anhui Experiment, a pilot experiment of "Yangtze River Geoscience Project "conducted in October,2015,is a large active-source experiment using airgun sources. It was the first 3-dimensional seismic surve...The Anhui Experiment, a pilot experiment of "Yangtze River Geoscience Project "conducted in October,2015,is a large active-source experiment using airgun sources. It was the first 3-dimensional seismic survey with active sources in the Yangtze River. The sources are airguns in 20 fixed shot points,and the observation system consists mainly of109 permanent stations and 11 wide-angle profiles. Using the data from permanent stations,we investigated the seismic signals generated by airgun sources in the Yangtze River. The results show that the airgun signals are observable in the records from permanent stations to a maximum distance of 300 km. Further analysis on absolute amplitude of airgun signals shows that:( 1) the strength of airgun signals is of the order of10 nm at 50 km away from the source,and then,decreases significantly to less than 1nm at 200 km;( 2) an azimuthal anisotropy is observed in spatial distribution of the strength of airgun signals,which may be related to the geometry of Yangtze River; and( 3) a low ambient noise level is essential for retrieving weak airgun signals from the records,and the high-quality China National Seismic Network and regional networks offer a great opportunity to retrieving airgun signals with amplitude as small as nanometers.展开更多
In this paper, a new of oxygen fugaeity controltechnique that can be widely applied to in-situ measurement of the grain interior electrical conductivities of minerals and rocks is presented for high temperature and hi...In this paper, a new of oxygen fugaeity controltechnique that can be widely applied to in-situ measurement of the grain interior electrical conductivities of minerals and rocks is presented for high temperature and high pressure. Inside the sample assembly, a metal and corresponding metal oxide form a solid oxygen buffer. The principle of this technique is to randomly monitor and adjust oxygen fugacity in the large-volume multi-anvil press by changing the types of solid oxygen buffer, metal shielding case and electrodes. At a pressure of up to 5.0 GPa and a temperature of up to 1423 K, the electrical conductivities of the dry peridotite are tested under the conditions of different oxygen fugacities. By virtue of this new technique, more and more reasonable and accurate laboratory electrical property data will be successfully obtained under controlled thermodynamic conditions.展开更多
Decompensated cirrhosis is characterized by chronic inflammation and severe portal hypertension leading to systemic circulatory dysfunction.Albumin infusion has been widely used in decompensated cirrhosis in patients ...Decompensated cirrhosis is characterized by chronic inflammation and severe portal hypertension leading to systemic circulatory dysfunction.Albumin infusion has been widely used in decompensated cirrhosis in patients with spontaneous bacterial peritonitis,large-volume paracentesis and hepatorenal syndrome.Emerging data suggest long-term albumin infusion has both oncotic and non-oncotic properties which may improve the clinical outcomes in decompensated cirrhosis patients.We review the current literature on both the established and potential role of albumin,and specifically address the controversies of long-term albumin infusion in decompensated cirrhosis patients.展开更多
In order to further deepen the understanding of seismic wave propagation characteristics induced by the large volume airgun source,experimental data from multiple fixed excitation points in Fujian Province were used t...In order to further deepen the understanding of seismic wave propagation characteristics induced by the large volume airgun source,experimental data from multiple fixed excitation points in Fujian Province were used to obtain the equivalent single excitation high signal-to-noise ratio velocity and displacement records through linear stacking and simulation techniques.Then the peak displacements of different epicentral distances were used to calculate the equivalent magnitude of the airgun source excitation at different fixed excitation points so as to establish the attenuation relationship between equivalent magnitude,epicenter distance and velocity peak.Our results show that:①Within 270 km of epicentral distance,for the large-volume airgun’s single shot,the peak velocity range is about 700-4 nm/s,and the peak displacement range is about 200.0-0.2 nm;②The equivalent magnitude of the P-wave from the airgun source with a total capacity of 8,000 in 3 is 0.181-0.760,and the equivalent magnitude of the S-wave is 0.294-0.832.By contrast,the equivalent magnitude of the P-wave from the airgun source with a total capacity of 12,000 in 3 is 0.533-0.896,and the equivalent magnitude of the S-wave is 0.611-0.946.The S-wave energy is greater than the P-wave energy,and the excitation efficiency varies greatly with different excitation environment;③The peak velocity increases with the equivalent magnitude,and decreases with the epicentral distance.The vertical component of the P-wave peak velocity is the largest among those three components,while the S-wave has the smallest vertical component and similar horizontal components.Hence,our research can provide an important basis for the quantitative judgment of the seismic wave propagation distance using the airgun and the design of the observation system in deep exploration or monitoring with airgun.展开更多
Objective:To evaluate the efficacy of transbronchoscopic large volume lung lavage in the treatment of pneumoconiosis complicated with chronic obstructive pulmonary disease(COPD).Methods:The clinical data of 80 patient...Objective:To evaluate the efficacy of transbronchoscopic large volume lung lavage in the treatment of pneumoconiosis complicated with chronic obstructive pulmonary disease(COPD).Methods:The clinical data of 80 patients with pneumoconiosis complicated with COPD admitted to our hospital from June 2017 to January 2019 were retrospectively analyzed.40 patients in the control group were treated with conventional drugs and 40 patients in the observation group treated with conventional drugs plus transbronchoscopic large-volume lung lavage.Dyspnea score and healthy quality of life were compared between the two groups.Results:the scores of dyspnea in the observation group were significantly lower than those in the control group at 12,24 and 48 weeks after treatment,and the(SGRQ)scores of George’s respiratory problems questionnaire in the observation group were significantly lower than those in the control group at 12,24 and 48 weeks after treatment.Conclusion:Thetransbronchoscopic large volume of lung lavage has a significant effect on the treatment of pneumoconiosis patients with COPD,which can effectively reduce the degree of dyspnea and improve the quality of life.展开更多
It is essential to determine the occurrence of emerging organic contaminants(EOCs),such as pharmaceuticals and personal care products(PPCPs),in the ambient environment to address growing public concerns.However,such a...It is essential to determine the occurrence of emerging organic contaminants(EOCs),such as pharmaceuticals and personal care products(PPCPs),in the ambient environment to address growing public concerns.However,such analysis is quite challenging due to the low trace level of such contaminants in water,which therefore requires several litres of water samples.In this study,a large volume solid phase extraction(LV-SPE)device was developed and evaluated for its performance in monitoring PPCPs as an example.Relatively good recoveries and reproducibility were obtained under specific operating conditions:a water sample volume of no more than 20 L,a flow rate not exceeding 120 mL/min,and a methanol elution volume of at least 30 mL.In addition,the results from the onsite enrichment approach using LV-SPE were compared with those from the conventional approach using a standard SPE device in the laboratory for real groundwater samples.Among the eight selected PPCPs(nalidixic acid,carbamazepine,bezafibrate,clofibric acid,sulfadiazine,sulfamethoxypyridazine,sulfamethazine and sulfamonomethoxine),LV-SPE approach detected more target compounds.While the detected concentrations were generally comparable,slightly higher concentrations were observed for carbamazepine,clofibric acid,sulfadiazine and sulfamethazine using the LV-SPE method.The developed LV-SPE device provides an alternative approach for trace analysis of PPCPs and may also be applicable for other emerging organic contaminants.展开更多
To decipher the organizational logic of complex brain circuits,it is important to chart long-distance pathways while preserving micron-level accuracy of local network.However,mapping the neuronal projections with indi...To decipher the organizational logic of complex brain circuits,it is important to chart long-distance pathways while preserving micron-level accuracy of local network.However,mapping the neuronal projections with individual-axon resolution in the large and complex primate brain is still challenging.Herein,we describe a highly efficient pipeline for three-dimensional mapping of the entire macaque brain with subcellular resolution.The pipeline includes a novel poly-N-acryloyl glycinamide(PNAGA)-based embedding method for long-term structure and fluorescence preservation,high-resolution and rapid whole-brain optical imaging,and image post-processing.The cytoarchitectonic information of the entire macaque brain was acquired with a voxel size of 0.32μm×0.32μm×10μm,showing its anatomical structure with cell distribution,density,and shape.Furthermore,thanks to viral labeling,individual long-distance projection axons from the frontal cortex were for the first time reconstructed across the entire brain hemisphere with a voxel size of 0.65μm×0.65μm×3μm.Our results show that individual cortical axons originating from the prefrontal cortex simultaneously target multiple brain regions,including the visual cortex,striatum,thalamus,and midbrain.This pipeline provides an efficient method for cellular and circuitry investigation of the whole macaque brain with individual-axon resolution,and can shed light on brain function and disorders.展开更多
Annually,10%of cirrhotic patients with ascites develop refractory ascites for which large-volume paracentesis(LVP)is a frequently used therapeutic procedure.LVP,although a safe method,is associated with circulatory dy...Annually,10%of cirrhotic patients with ascites develop refractory ascites for which large-volume paracentesis(LVP)is a frequently used therapeutic procedure.LVP,although a safe method,is associated with circulatory dysfunction in a significant percentage of patients,which is termed para-centesis-induced circulatory dysfunction(PICD).PICD results in faster reaccumulation of ascites,hyponatremia,renal impairment,and shorter survival.PICD is diagnosed through laboratory results,with increases of>50%of baseline plasma renin activity to a value≥4 ng/mL/h on the fifth to sixth day after paracentesis.In this review,we discuss the pathophysi-ology and prevention of PICD.展开更多
基金supported by the National Key Research and Development Program of China(2022YFB3706600 and 2023YFA1406200)the National Natural Science Founda-tion of China(42272041,52302043,12304015,41902034,and 12011530063)+1 种基金the Jilin University High-level Innovation Team Foundation,China(2021TD-05)the National Major Science Facility Synergetic Extreme Condition User Facility Achievement Transformation Platform Construction(2021FGWCXNLJSKJ01).
文摘Ultrahigh pressure generation at high temperatures is technologically challenging for large sample volumes.In this study,we successfully generated pressures of 37.3-40.4 GPa at 1900-2100 K in a Walker-type large-volume press(LVP).Expansion of the pressure range at high temperatures was achieved by adapting newly designed ZK01F tungsten carbide(WC)anvils with tapered surfaces and using cell assemblies with an^(-1) mm^(3) sample volume and hard materials,as well as by applying certain adjustments to the apparatus.The pressure efficiencies of the different types of WC anvils and cell assemblies were also studied.Using the above-mentioned techniques,we successfully synthesized and characterized bulk samples of nearly pure sp3-hybridized ultrahard amorphous carbon,core-shell nanocrystals with high Néel temperatures,as well as large-sized single crystals of lower-mantle minerals.The developed LVP techniques presented here could enable the exploration of the chemical and physical properties of novel materials and Earth’s interior.
基金open fund of Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(Yangtze University)YQZC202404.
文摘Tight gas reservoirs are often characterized by pronounced heterogeneity and poor continuity,resulting in wide variability in production enhancement and net present value(NPV)for different geological parameter combinations(see e.g.,the Ordos Basin).The conditions governing geological adaptability remain insufficiently defined.To address these challenges,this study integrates large-volume hydraulic fracturing,numerical production simulation,and economic evaluation to elucidate the mechanisms by which large-scale fracturing enhances fracture parameters in tight gas formations.The analysis reveals that,for identical proppant and fluid volumes,increasing the fracturing injection rate leads to longer and taller fractures.Over the same production period,this results in a more rapid decline in average reservoir pressure and a higher cumulative gas output.Through simulations conducted at varying injection rates across 11 production wells in the target block,the study demonstrates that large-volume fracturing can effectively connect otherwise isolated tight gas pockets,enlarge the drainage area,and substantially boost individual well production.A comparative assessment of simulation outcomes and economic performance shows that large-volume fracturing significantly improves gas recovery and NPV compared to conventional smaller-scale treatments.The study identifies the key geological indicators that influence differences in production enhancement and economic returns between small-and large-volume fracturing strategies.Based on these findings,a decision matrix is developed(utilizing a trapezoidal membership function)to evaluate the geological suitability of large-volume fracturing in tight gas reservoirs.This matrix is applied to the 11 target wells,with the evaluation results aligning well with those obtained from numerical simulations.
基金the National Natural Science Foundation of China(Grant Nos.42272041,41902034,52302043,12304015,52302043,and 12011530063)the National Major Science Facility Synergetic Extreme Condition User Facility Achievement Transformation Platform Construction(Grant No.2021FGWCXNLJSKJ01)+2 种基金the China Postdoctoral Science Foundation(Grant Nos.2022M720054 and 2023T160257)the National Key Research and Development Program of China(Grant No.2022YFB3706602)the Jilin Univer-sity High-level Innovation Team Foundation,China(Grant No.2021TD-05).
文摘Deformation can change the transition pathway of materials under high pressure,thus significantly affects physical and chemical properties of matters.However,accurate pressure calibration under deformation is challenging and thereby causes relatively large pressure uncertainties in deformation experiments,resulting in the synthesis of complex multiphase materials.Here,pressure generations of three types of deformation assemblies were well calibrated in a Walker-type largevolume press(LVP)by electrical resistance measurements combined with finite element simulations(FESs).Hard Al_(2)O_(3) or diamond pistons in shear and uniaxial deformation assemblies significantly increase the efficiency of pressure generation compared with the conventional quasi-hydrostatic assembly.The uniaxial deformation assembly using flat diamond pistons possesses the highest efficiency in these deformation assemblies.This finding is further confirmed by stress distribution analysis based on FESs.With this deformation assembly,we found shear can effectively promote the transformation of C60 into diamond under high pressure and realized the synthesis of phase-pure diamond at relatively moderate pressure and temperature conditions.The present developed techniques will help improve pressure efficiencies in LVP and explore the new physical and chemical properties of materials under deformation in both science and technology.
基金Supported by the National Key Research and Development Program of China under Grant No 2016YFA0401503the Science Challenge Project under Grant No TZ2016001the National Natural Science Foundation of China under Grant No 11427810
文摘Neutron diffraction techniques of large-volume samples at high pressure using compact opposed-anvil cells are developed at a reactor neutron source, China＇s Mianyang research reactor. We achieve a high-pressure condition of in situ neutron diffraction by means of a newly designed large-volume opposed-anvil cell. This pressure calibration is based on resistance measurements of bismuth and the neutron diffraction of iron. Pressure calibration experiments are performed at room temperature for a new cell using the tungsten carbide anvils with a tapered angle of 30°, Φ4.5 mm culet diameter and the metal-nonmetal composite gasket with a thickness of 2 mm. Transitions in Bi（Ⅰ–Ⅱ 2.55 GPa, Ⅱ–V 7.7 GPa） are observed at 100 and 300 kN, respectively, by resistance measurements.The pressure measurement results of neutron diffraction are consistent with resistance measurements of bismuth.As a result, pressures up to about 7.7 GPa can routinely and stably be achieved using this apparatus, with the sample volume of 9 mm^3.
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 paper shows selected aspects of the microclimate change inside the selected type of the large-volume buildings--sacral buildings and for comparison--in the residential apartment buildings, caused by the heat emitted by people. Microclimate parameters such as air temperature or air relative humidity change because of heat emission from people staying inside there. Exemplary methods and results of research conducted in the existing sacral buildings and in the residential apartment buildings are shown. It is based on author＇s research, whose novelty is the research of the human heat emission in case of a big number of people staying inside a large-volume building. It can be useful for sacral buildings and other large-volume buildings design and for a microclimate shaping. In some large-volume buildings as the sacral buildings with a big number of people staying inside at the same time heat emitted from people significantly influences on a microclimate. Human heat streams can be useful as a part of the heat balance of the room.
基金The authors thank LEAP Technologies(Carrboro,NC,USA)for providing the technical support of the automated solid-phase extraction system.
文摘A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass spectrometry.Thewater samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction plates.The method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface water.For a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most analytes.For the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for mostanalytes.The new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other chemicals.As a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water.
基金Supported by Sanming Project of Medicine in Shenzhen,No.SZSM202211029.
文摘For cirrhotic refractory ascites,diuretics combined with albumin and vasoactive drugs are the first-line choice for ascites management.However,their therapeutic effects are limited,and most refractory ascites do not respond to medication treat-ment,necessitating consideration of drainage or surgical interventions.Con-sequently,numerous drainage methods for cirrhotic ascites have emerged,including large-volume paracentesis,transjugular intrahepatic portosystemic shunt,peritoneovenous shunt,automated low-flow ascites pump,cell-free and concentrated ascites reinfusion therapy,and peritoneal catheter drainage.This review introduces the advantages and disadvantages of these methods in different aspects,as well as indications and contraindications for this disease.
文摘To provide an overview of the properties of human serum albumin(HSA), and to review the evidence for the use of human albumin solution(HAS) in critical illness, sepsis and cirrhosis. A MEDLINE search was performed using the terms "human albumin", "critical illness", "sepsis" and "cirrhosis". The references of retrieved articles were reviewed manually. Studies published between 1980 and 2014 were selected based on quality criteria. Data extraction was performed by all authors. HSA is the main plasma protein contributing greatly to its oncotic pressure. HSA demonstrates important binding properties for endogenous and exogenous toxins, drugs and drug metabolites that account for its anti-oxidant and anti-inflammatory properties. In disease states, hypoalbuminaemia is secondary to decreased HSA production, increased loss or transcapillary leakage into the interstitial space. HSA function can be also altered in disease with reduced albumin binding capacity and increased production of modified isoforms. HAS has been used as volume expander in critical illness, but received criticism due to cost and concerns regarding safety. More recent studies confirmed the safety of HAS, but failed to show any survival benefit compared to the cheaper crystalloid fluids, therefore limiting its use. On the contrary, in cirrhosis there is robust data to support the efficacy of HAS for the prevention of circulatory dysfunction post-large volume paracentesis and in the context of spontaneous bacterial peritonitis, and for the treatment of hepato-renal syndrome and hypervolaemic hyponatraemia. It is likely that not only the oncotic properties of HAS are beneficial in cirrhosis, but also its functional properties, as HAS replaces the dysfunctional HSA. The role of HAS as the resuscitation fluid of choice in critically ill patients with cirrhosis, beyond the established indications for HAS use, should be addressed in future studies.
基金supported by National Natural Science Foundation of China(Nos.11875256,12005023,11705202)Scientific Research Fund Project of Anhui Jianzhu University(No.2020QDZ09)Anhui Provincial Natural Science Foundation(No.1808085MA12).
文摘In this paper,a three-dimensional non-equilibrium steady arc model is used to investigate the temperature,velocity and electromagnetic field in multi-cathode arc torch,and the formation mechanism of a large-area,uniform and diffused arc plasma is analyzed.The numerical simulation results show that a large volume plasma region can be formed in the central region of the generator during discharge.During this process,the maximum electron temperature appears near the cathode and in the central convergence region,while the maximum heavy particle temperature only appears in the central convergence region.This phenomenon is consistent with the experimental arc images.Near the cathode tip,the arc column is in a contraction state.In the area slightly away from the cathode,the six arc columns begin to join together.In the plasma generator,there is a large-scale current distribution in all directions of X,Y and Z,forming a stable arc plasma with a wide range of diffusion.The calculated electron temperature distribution is in good agreement with the measured electron temperature.The results suggest that the largearea diffused arc plasma in the multi-cathode arc torch is the combined effect of current distribution,convection heat transfer and heat conduction.
基金jointly supported by the Fundamental Research Funds for Central Public Welfare Research Institutes(DQJB15B09)National Natural Science Foundation of China(41574052,41374070)Academician of Chen Yong Workstation Project of Yunnan Province(2014IC007)
文摘The Anhui Experiment, a pilot experiment of "Yangtze River Geoscience Project "conducted in October,2015,is a large active-source experiment using airgun sources. It was the first 3-dimensional seismic survey with active sources in the Yangtze River. The sources are airguns in 20 fixed shot points,and the observation system consists mainly of109 permanent stations and 11 wide-angle profiles. Using the data from permanent stations,we investigated the seismic signals generated by airgun sources in the Yangtze River. The results show that the airgun signals are observable in the records from permanent stations to a maximum distance of 300 km. Further analysis on absolute amplitude of airgun signals shows that:( 1) the strength of airgun signals is of the order of10 nm at 50 km away from the source,and then,decreases significantly to less than 1nm at 200 km;( 2) an azimuthal anisotropy is observed in spatial distribution of the strength of airgun signals,which may be related to the geometry of Yangtze River; and( 3) a low ambient noise level is essential for retrieving weak airgun signals from the records,and the high-quality China National Seismic Network and regional networks offer a great opportunity to retrieving airgun signals with amplitude as small as nanometers.
基金supported by the Knowledge Innovation Key Orientation Project of the Chinese Academy of Sciences (CAS) (Grant Nos. KZCX2-YW-Q08-3-4,KZCX2-YW-QN110,and KZCX3-SW-124)Large-scale Scientific Apparatus Development Program of CAS (Grant No. YZ200720)+1 种基金the National High Technology Research and Development Program of China (Grant No. 2006AA09Z205)the National Natural Science Foundation of China (Grant Nos. 40974051,40704010 and 40573046)
文摘In this paper, a new of oxygen fugaeity controltechnique that can be widely applied to in-situ measurement of the grain interior electrical conductivities of minerals and rocks is presented for high temperature and high pressure. Inside the sample assembly, a metal and corresponding metal oxide form a solid oxygen buffer. The principle of this technique is to randomly monitor and adjust oxygen fugacity in the large-volume multi-anvil press by changing the types of solid oxygen buffer, metal shielding case and electrodes. At a pressure of up to 5.0 GPa and a temperature of up to 1423 K, the electrical conductivities of the dry peridotite are tested under the conditions of different oxygen fugacities. By virtue of this new technique, more and more reasonable and accurate laboratory electrical property data will be successfully obtained under controlled thermodynamic conditions.
基金Supported by Nurturing Clinician Scientist Scheme Award by SingHealth Duke-NUS Medicine Academic Medicine Programme(Medicine ACP),Changi General Hospital Research Grant.
文摘Decompensated cirrhosis is characterized by chronic inflammation and severe portal hypertension leading to systemic circulatory dysfunction.Albumin infusion has been widely used in decompensated cirrhosis in patients with spontaneous bacterial peritonitis,large-volume paracentesis and hepatorenal syndrome.Emerging data suggest long-term albumin infusion has both oncotic and non-oncotic properties which may improve the clinical outcomes in decompensated cirrhosis patients.We review the current literature on both the established and potential role of albumin,and specifically address the controversies of long-term albumin infusion in decompensated cirrhosis patients.
基金the National Natural Science Foundation of China(41790461)
文摘In order to further deepen the understanding of seismic wave propagation characteristics induced by the large volume airgun source,experimental data from multiple fixed excitation points in Fujian Province were used to obtain the equivalent single excitation high signal-to-noise ratio velocity and displacement records through linear stacking and simulation techniques.Then the peak displacements of different epicentral distances were used to calculate the equivalent magnitude of the airgun source excitation at different fixed excitation points so as to establish the attenuation relationship between equivalent magnitude,epicenter distance and velocity peak.Our results show that:①Within 270 km of epicentral distance,for the large-volume airgun’s single shot,the peak velocity range is about 700-4 nm/s,and the peak displacement range is about 200.0-0.2 nm;②The equivalent magnitude of the P-wave from the airgun source with a total capacity of 8,000 in 3 is 0.181-0.760,and the equivalent magnitude of the S-wave is 0.294-0.832.By contrast,the equivalent magnitude of the P-wave from the airgun source with a total capacity of 12,000 in 3 is 0.533-0.896,and the equivalent magnitude of the S-wave is 0.611-0.946.The S-wave energy is greater than the P-wave energy,and the excitation efficiency varies greatly with different excitation environment;③The peak velocity increases with the equivalent magnitude,and decreases with the epicentral distance.The vertical component of the P-wave peak velocity is the largest among those three components,while the S-wave has the smallest vertical component and similar horizontal components.Hence,our research can provide an important basis for the quantitative judgment of the seismic wave propagation distance using the airgun and the design of the observation system in deep exploration or monitoring with airgun.
基金Social Benefiting Project by Science and Technology for Ningxia Hui Autonomous Region:Comprehensive Demonstration of Integrated Prevention and Control Technology of Pneumoconiosis in Ningdong Coal Mine(Project No.:KJHM201503)。
文摘Objective:To evaluate the efficacy of transbronchoscopic large volume lung lavage in the treatment of pneumoconiosis complicated with chronic obstructive pulmonary disease(COPD).Methods:The clinical data of 80 patients with pneumoconiosis complicated with COPD admitted to our hospital from June 2017 to January 2019 were retrospectively analyzed.40 patients in the control group were treated with conventional drugs and 40 patients in the observation group treated with conventional drugs plus transbronchoscopic large-volume lung lavage.Dyspnea score and healthy quality of life were compared between the two groups.Results:the scores of dyspnea in the observation group were significantly lower than those in the control group at 12,24 and 48 weeks after treatment,and the(SGRQ)scores of George’s respiratory problems questionnaire in the observation group were significantly lower than those in the control group at 12,24 and 48 weeks after treatment.Conclusion:Thetransbronchoscopic large volume of lung lavage has a significant effect on the treatment of pneumoconiosis patients with COPD,which can effectively reduce the degree of dyspnea and improve the quality of life.
基金This research was financially supported by the Major Science and Technology Program for Water Pollution Control and Treatment in China(Grant No.2017ZX07202004).
文摘It is essential to determine the occurrence of emerging organic contaminants(EOCs),such as pharmaceuticals and personal care products(PPCPs),in the ambient environment to address growing public concerns.However,such analysis is quite challenging due to the low trace level of such contaminants in water,which therefore requires several litres of water samples.In this study,a large volume solid phase extraction(LV-SPE)device was developed and evaluated for its performance in monitoring PPCPs as an example.Relatively good recoveries and reproducibility were obtained under specific operating conditions:a water sample volume of no more than 20 L,a flow rate not exceeding 120 mL/min,and a methanol elution volume of at least 30 mL.In addition,the results from the onsite enrichment approach using LV-SPE were compared with those from the conventional approach using a standard SPE device in the laboratory for real groundwater samples.Among the eight selected PPCPs(nalidixic acid,carbamazepine,bezafibrate,clofibric acid,sulfadiazine,sulfamethoxypyridazine,sulfamethazine and sulfamonomethoxine),LV-SPE approach detected more target compounds.While the detected concentrations were generally comparable,slightly higher concentrations were observed for carbamazepine,clofibric acid,sulfadiazine and sulfamethazine using the LV-SPE method.The developed LV-SPE device provides an alternative approach for trace analysis of PPCPs and may also be applicable for other emerging organic contaminants.
基金supported by the National Basic Research Program of China(973 Project2015CB755602)+3 种基金the National Natural Science Foundation of China(61721092,61890953,31871088,and 81871082)Key-Area Research and Development Program of Guangdong Province(2019B030335001)CAMS Innovation Fund for Medical Sciences(2019-I2M-5-014)the Director Fund of Wuhan National Laboratory for Optoelectronics。
文摘To decipher the organizational logic of complex brain circuits,it is important to chart long-distance pathways while preserving micron-level accuracy of local network.However,mapping the neuronal projections with individual-axon resolution in the large and complex primate brain is still challenging.Herein,we describe a highly efficient pipeline for three-dimensional mapping of the entire macaque brain with subcellular resolution.The pipeline includes a novel poly-N-acryloyl glycinamide(PNAGA)-based embedding method for long-term structure and fluorescence preservation,high-resolution and rapid whole-brain optical imaging,and image post-processing.The cytoarchitectonic information of the entire macaque brain was acquired with a voxel size of 0.32μm×0.32μm×10μm,showing its anatomical structure with cell distribution,density,and shape.Furthermore,thanks to viral labeling,individual long-distance projection axons from the frontal cortex were for the first time reconstructed across the entire brain hemisphere with a voxel size of 0.65μm×0.65μm×3μm.Our results show that individual cortical axons originating from the prefrontal cortex simultaneously target multiple brain regions,including the visual cortex,striatum,thalamus,and midbrain.This pipeline provides an efficient method for cellular and circuitry investigation of the whole macaque brain with individual-axon resolution,and can shed light on brain function and disorders.
文摘Annually,10%of cirrhotic patients with ascites develop refractory ascites for which large-volume paracentesis(LVP)is a frequently used therapeutic procedure.LVP,although a safe method,is associated with circulatory dysfunction in a significant percentage of patients,which is termed para-centesis-induced circulatory dysfunction(PICD).PICD results in faster reaccumulation of ascites,hyponatremia,renal impairment,and shorter survival.PICD is diagnosed through laboratory results,with increases of>50%of baseline plasma renin activity to a value≥4 ng/mL/h on the fifth to sixth day after paracentesis.In this review,we discuss the pathophysi-ology and prevention of PICD.
