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Differences in Light Response Curve and CO_2 Response Curve of Korla Fragrant Pear Trees in Different Training Systems 被引量:2
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作者 江振斌 廖康 +5 位作者 曼苏尔.那斯尔 牛莹莹 庞洪翔 孙琪 徐乐 章世奎 《Agricultural Science & Technology》 CAS 2016年第8期1762-1766,共5页
[Objective] This study was conducted to evaluate three training systems for Korla fragrant pear trees by comparing the characteristic parameters of light response curve and CO2 response curve, and to provide some theo... [Objective] This study was conducted to evaluate three training systems for Korla fragrant pear trees by comparing the characteristic parameters of light response curve and CO2 response curve, and to provide some theoretical basis for improving the pruning techniques of Korla fragrant pear trees. [Method] The light response curve and CO2 response curve of the trees trained to three systems were measured by LI-6400 portable photosynthesis system. The SPAD value was measured using SPAD-502 chlorophyll meter, and specific leaf weight was calculated, to evaluate the effects of the three training systems. [Result] The CO2 response curves of the three training systems were basically in agreement with their light response curves, but there were some differences in their characteristic parameters. Among the three training systems, the maximum net photosynthetic rate, apparent quantum yield and light compensation point of espalier trained trees were the highest, while their light saturation point was the lowest. The CO2 saturation point of delayed-open central leader trained trees and open center trained trees were 1 752 and 1 665 μmol/mol, both of which were much higher than that of espalier trained trees. In addition, the carboxylation efficiency and photorespiration rate of espalier trained trees were both higher than those of delayed-open central leader trained trees and open center trained trees, while the CO2 compensation point of espalier trained trees was the lowest. The leaf SPAD value of espalier trained trees was the largest, followed by that of open center trained trees, and the leaf SPAD value of delayed-open central leader trained trees was the smallest. In addition, the leaf area and specific leaf weight of espalier trained trees were both the highest, followed by those of open center trained trees. [Conclusion] Among the training systems for Korla fragrant pear trees, the espalier training system had better ability to capture light, higher photosynthetic productivity and strongest adaptability to light environment, and open center training system takes the second place. On the contrary, delayed-open central leader training system has the weakest adaptability to light environment, but it can adapt to a higher CO2 concentration. In summary, for the training of Korla fragrant pear trees, espalier training system, which has the highest theoretical yield, is the best among the three training systems, and delayed-open central leader training system is the worst. 展开更多
关键词 Korla fragrant pear Training system Light response curve co2 response curve
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Ideal Drift Response Curve for Robust Optimal Damper Design for Elastic-Plastic MDOF Structures under Multi-Level Earthquakes Dedicated to Professor Karl S.Pister for his 95th birthday
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作者 Hiroki Akehashi Izuru Takewaki 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第12期1181-1207,共27页
A new method of robust damper design is presented for elastic-plastic multi-degree-of-freedom(MDOF)building structures under multi-level ground motions(GMs).This method realizes a design that is effective for various ... A new method of robust damper design is presented for elastic-plastic multi-degree-of-freedom(MDOF)building structures under multi-level ground motions(GMs).This method realizes a design that is effective for various levels of GMs.The robustness of a design is measured by an incremental dynamic analysis(IDA)curve and an ideal drift response curve(IDRC).The IDRC is a plot of the optimized maximum deformation under a constraint on the total damper quantity vs.the design level of the GMs.The total damper quantity corresponds to the total cost of the added dampers.First,a problem of generation of IDRCs is stated.Then,its solution algorithm,which consists of the sensitivity-based algorithm(SBA)and a local search method,is proposed.In the application of the SBA,the passive added dampers are removed sequentially under the specified-level GMs.On the other hand,the proposed local search method can search the optimal solutions for a constant total damper quantity under GMs’increased levels.In this way,combining these two algorithms enables the comprehensive search of the optimal solutions for various conditions of the status of the GMs and the total damper quantity.The influence of selecting the type of added dampers(oil,hysteretic,and so on)and the selection of the input GMs on the IDRCs are investigated.Finally,a robust optimal design problem is formulated,and a simple local search-based algorithm is proposed.A simple index using the IDRC and the IDA curve of the model is used as the objective function.It is demonstrated that the proposed algorithm works well in spite of its simplicity. 展开更多
关键词 Optimal damper placement robust damper design multi-level earthquake ideal drift response curve elastic-plastic MDOF model viscous damper hysteretic damper
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Research on Light Response Curve Fitting Model of Four Chamaenerion Plants on the Serzilla Mountains
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作者 Lusheng Wan Zhen Xing +2 位作者 Xinyue Chang Jiang Liu Guorong Zhang 《American Journal of Plant Sciences》 2018年第8期1630-1645,共16页
In order to study the applicability of different light response models to the photoresponse curves of four species of Chamaenerion, four species of Chamaenerion collected from Serzilla were used as test materials. Fou... In order to study the applicability of different light response models to the photoresponse curves of four species of Chamaenerion, four species of Chamaenerion collected from Serzilla were used as test materials. Four common photosynthetic models were used to fit the photosynthetic response curve of the leaves. The results show that: 1) The effect of different photosynthetic response models on photosynthetic response curve of the genus chromasia was different. The fitted value of the correction model of right angled hyperbola was closest to the measured value, the R2 was 0.998, and RE was 0.216. 2) In terms of fitting the photosynthetic parameters, the initial quantum efficiency, light compensation point and dark respiration rate were suitable for fitting with non-right angle hyperbolic model. In terms of fitting the photosynthetic parameters, the initial quantum efficiency, light compensation point and dark respiration rate were suitable for fitting with non-right angle hyperbolic model. 3) The photosynthetic characteristics of C. angustifolium subsp. circumvagum reflect the negative response to high altitude radiation. Under strong radiation, the photosynthetic rate, apparent quantum efficiency, and light saturation point are low. On the other hand, C. conspersum has a positive response to high altitude radiation. C. angustifolium and C. latifolium has a higher light compensation point and higher light saturation point, but it is also positive for high altitude radiation. The response is only a choice of light intensity at different elevations, which also explains the distribution of C. angustifolium and C. latifolium in the salmonella with a single elevation, habitat, and slope. 展开更多
关键词 ALPINE Plant Chamaenerion Optical response curve RIGHT Angle HYPERBOLIC Correction Model
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Energy Dependence of the New Gafchromic EBT3 Film:Dose Response Curves for 50 KV, 6 and 15 MV X-Ray Beams
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作者 Guerda Massillon-JL Sou-Tung Chiu-Tsao +1 位作者 Ivan Domingo-Munoz Maria F. Chan 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2012年第2期60-65,共6页
Purpose: To study and compare the dose response curves of the new GafChromic EBT3 film for megavoltage and kilovoltage x-ray beams, with different spatial resolutions. Methods: EBT3 films (lot#A101711-02) were exposed... Purpose: To study and compare the dose response curves of the new GafChromic EBT3 film for megavoltage and kilovoltage x-ray beams, with different spatial resolutions. Methods: EBT3 films (lot#A101711-02) were exposed to each x-ray beam (6 MV, 15 MV, and 50 kV) at 7 dose values (50-3200 cGy). Each film piece was scanned three consecutive times in the center of Epson 10000XL flatbed scanner in 48-bit color at two separate spatial resolutions of 75 and 300 dpi. The data were analyzed using ImageJ and, for each scanned image, a region of interest (ROI) of 2 × 2 cm2 at the field center was selected to obtain the mean pixel value with its standard deviation in the ROI. For each energy, dose value and spatial resolution, the average net optical density (netOD) and its associated uncertainty were determined. The Student’s t-test was performed to evaluate the statistical differences between the net OD/dose values of the three energy modalities, with different color channels and spatial resolutions. Results and Discussion: The dose response curves for the three energy modalities were compared in three color channels. Weak energy dependence was found. For doses above 100 cGy, no statistical differences were observed between 6 and 15 MV beams, regardless of spatial resolution and color channel. However, statistical differences were observed between 50 kV and the megavoltage beams. The degree of energy dependence (from MV to 50 kV) was found to be a function of color channel, dose level, and spatial resolution. Conclusions: The dose response curves for GafChromic EBT3 films were found to be weakly dependent on the energy of the photon beams from 6 MV to 15 MV. For very low energy photon (e.g. 50 kV), variation of more than 11% due to the energy-dependence is observed, depending on the absorbed dose, spatial resolution and color channel used. 展开更多
关键词 Radiochromic FILM EBT3 FILM Dose response curve Quality ASSURANCE LOW-ENERGY PHOTONS
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Modified non-rectangular hyperbola equation with plant height for photosynthetic light-response curves of Potentilla anserina and Elymus nutans at various growth phases in the Heihe River Basin, Northwest China 被引量:1
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作者 LIU Junjie WANG Xiaoping +8 位作者 RONG Zhanlei GAO Yunfei ZHANG Guangde WANGWenbin GE Lijuan MAO Yahua GUO Zhaoxia WANG Qingtao ZHAO Chuanyan 《Journal of Arid Land》 SCIE CSCD 2019年第5期764-773,共10页
The non-rectangular hyperbola(NRH)equation is the most popular method that plots the photosynthetic light-response(PLR)curve and helps to identify plant photosynthetic capability.However,the PLR curve can't be plo... The non-rectangular hyperbola(NRH)equation is the most popular method that plots the photosynthetic light-response(PLR)curve and helps to identify plant photosynthetic capability.However,the PLR curve can't be plotted well by the NRH equation at different plant growth phases due to the variations of plant development.Recently,plant physiological parameters have been considered into the NRH equation to establish the modified NRH equation,but plant height(H),an important parameter in plant growth phases,is not taken into account.In this study,H was incorporated into the NRH equation to establish the modified NRH equation,which could be used to estimate photosynthetic capability of herbage at different growth phases.To explore photosynthetic capability of herbage,we selected the dominant herbage species Potentilla anserina L.and Elymus nutans Griseb.in the Heihe River Basin,Northwest China as the research materials.Totally,twenty-four PLR curves and H at different growth phases were measured during the growing season in 2016.Results showed that the maximum net photosynthetic rate and the initial slope of PLR curve linearly increased with H.The modified NRH equation,which is established by introducing H and an H-based adjustment factor into the NRH equation,described better the PLR curves of P.anserina and E.nutans than the original ones.The results may provide an effective method to estimate the net primary productivity of grasslands in the study area. 展开更多
关键词 plant height MODIFIED non-rectangular HYPERBOLA EQUATION Potentilla anserina Elymus nutans PHOTOSYNTHETIC light-response curve Qilian Mountains
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A numerical simulation study of CO2 injection for enhancing hydrocarbon recovery and sequestration in liquid-rich shales 被引量:9
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作者 Sumeer Kalra Wei Tian Xingru Wu 《Petroleum Science》 SCIE CAS CSCD 2018年第1期103-115,共13页
Less than 10% of oil is usually recovered from liquid-rich shales and this leaves much room for improvement, while water injection into shale formation is virtually impossible because of the extremely low permeability... Less than 10% of oil is usually recovered from liquid-rich shales and this leaves much room for improvement, while water injection into shale formation is virtually impossible because of the extremely low permeability of the formation matrix. Injecting carbon dioxide(CO2) into oil shale formations can potentially improve oil recovery. Furthermore, the large surface area in organicrich shale could permanently store CO2 without jeopardizing the formation integrity. This work is a mechanism study of evaluating the effectiveness of CO2-enhanced oil shale recovery and shale formation CO2 sequestration capacity using numerical simulation. Petrophysical and fluid properties similar to the Bakken Formation are used to set up the base model for simulation. Result shows that the CO_2 injection could increase the oil recovery factor from7.4% to 53%. In addition, petrophysical characteristics such as in situ stress changes and presence of a natural fracture network in the shale formation are proven to have impacts on subsurface CO2 flow. A response surface modeling approach was applied to investigate the interaction between parameters and generate a proxy model for optimizing oil recovery and CO2 injectivity. 展开更多
关键词 co2 EOR Tight formations EXPERIMENTALDESIGN response surface modeling Recovery of shaleliquid co2 sequestration
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Air/CO2 cooling garment: Description and benefits of use for subjects exposed to a hot and humid climate during physical activities 被引量:12
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作者 Chady Al Sayed Ludwig Vinches +3 位作者 Olivier Dupuy Wafa Douzi Benoit Dugue Stephane Halle 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第6期899-903,共5页
The severity of the hot and humid conditions to which miners are exposed increases as the depth of the work site increases.This can cause heat stress that can greatly affect the health and safety of workers.To resolve... The severity of the hot and humid conditions to which miners are exposed increases as the depth of the work site increases.This can cause heat stress that can greatly affect the health and safety of workers.To resolve this,a cooling garment has been developed that uses an atmospheric discharge of liquid CO2 to create a cool microclimate with an average temperature of 12.5(±0.4)℃ beneath the garment.To evaluate the garment's cooling efficiency,19 male subjects participated in an experimental procedure.The two modes,cooling on and off,were compared.Significant physiological differences were found between the two modes after minute 27(p<0.05)until the end of the recovery phase for the heart rate(maximum difference of 10 beats per minute)and the internal body temperature(maximum difference of 0.33℃).It was found that the modes also affected the subjects'perceptions.The ON-mode was associated with better well-being and thermal comfort,and reduced humidity sensation.Perceptions of exertion were lower in the ON-mode condition from minute 2.The findings provide strong evidence of the ability of this cooling garment to reduce heat stress in hot and humid conditions similar to those encountered in deep mines. 展开更多
关键词 COOLING GARMENT Deep mining HOT and humid Liquid co2 expansion PHYSIOLOGICAL measurements Perceptual responses
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Long-Term H2O and CO2 Trends in Conifer Disc Tree Rings and Meteorological Parameters
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作者 Ageev Boris Grigor'evich Gruzdev Aleksandr Nikolaevich +1 位作者 Bondarenko Svetlana Leonidovna Sapozhnikova Valeria Aleksandrovna 《Journal of Life Sciences》 2013年第9期1002-1008,共7页
Results of investigations into the CO2 content in tree disc rings by the method proposed here have shown that a considerable part of CO2 generated under cell respiration is found in tree stems. Besides, annual CO2 dis... Results of investigations into the CO2 content in tree disc rings by the method proposed here have shown that a considerable part of CO2 generated under cell respiration is found in tree stems. Besides, annual CO2 distribution in tree rings exhibits a well-defined cyclicity. Results obtained from investigations into long-term CO2 and H2O variations in tree discs performed by different methods are presented. Wavelet and spectral analyses of the relationship between CO2 and H2O variations in a Siberian stone pine disc and meteorological parameters were made. The CO2 annual distributions of seven spruce tree discs were examined by the Caterpiller-SSA method. Wood samples of Siberian stone pine and spruce trees were taken from the same site in Tomsk region (Siberia, Russia) that characterized by an optimum growth habitat. Conclusions are made regarding the response of the annual CO2 and H2O conifer disc tree ring distributions to different climatic factors. 展开更多
关键词 H2O co2 CYCLICITY tree rings laser photoacoustic gas analysis climate response
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The Yin-Yang of Stress and Senescence:Integrated Stress Response and SASP Crosstalk in Stem Cell Fate,Regeneration,and Disease
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作者 Douglas M.Ruden 《BIOCELL》 2026年第1期11-27,共17页
Stem cell fate decisions are increasingly understood through the dynamic interplay of two fundamental stress-adaptive programs:the integrated stress response(ISR)and the senescence-associated secretory phenotype(SASP)... Stem cell fate decisions are increasingly understood through the dynamic interplay of two fundamental stress-adaptive programs:the integrated stress response(ISR)and the senescence-associated secretory phenotype(SASP).These pathways act as a Yin-Yang system,balancing beneficial and detrimental outcomes across development,tissue homeostasis,and disease.On the yin(protective)side,transient ISR activation and acute SASP signaling foster adaptation,embryonic patterning,wound healing,and regeneration.On the yang(maladaptive)side,chronic ISR signaling and unresolved SASP output drive stem cell exhaustion,fibrosis,inflammation,and tumorigenesis.This duality highlights their roles as both guardians and disruptors of stem cell integrity.Mechanistically,ISR regulates translational control via eukaryotic initiation factor 2 alpha(eIF2α)phosphorylation and activating transcription factor 4(ATF4)-dependent transcription,while SASP reprograms the extracellular milieu through cytokines,growth factors,and proteases.Their crosstalk creates feedback loops that shape tissue niches and long-termstemcell potential.Framing ISR-SASP interactions through a Yin-Yang lens underscores the balance between resilience and decline,to offer new insights into regenerative medicine,anti-aging interventions,and cancer therapeutics. 展开更多
关键词 Integrated stress response(ISR) senescence-associated secretory phenotype(SASP) stem cells activating transcription factor 4(ATF4) eukaryotic initiation factor 2 alpha(eIF2α) inflammation cancer
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Modified ground response curve(GRC)in strain-softening rock mass based on the generalized Zhang-Zhu strength criterion considering over-excavation 被引量:6
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作者 Chen Xu Caichu Xia Changling Han 《Underground Space》 SCIE EI 2021年第5期585-602,共18页
The ground response curve(GRC)depicts the relationship between support reaction force and ground displacement,which improves the understanding of ground-support interaction and provides important references to the tun... The ground response curve(GRC)depicts the relationship between support reaction force and ground displacement,which improves the understanding of ground-support interaction and provides important references to the tunnel design.However,it is difficult to anticipate the tunneling-induced large deformation with sufficient reliability in soft rock with high geostress since the small strain theory is not applicable.When large deformation occurs,the tunnel needs to be over-excavated.Thus,the GRC should be modified considering the enlarged excavation radius since the actual excavation radius is usually greater than the designed one.To overcome the shortcomings of small strain theory in recognizing ground-support interaction under large deformation circumstances,a new large strain numerical approach for modifying the GRC was proposed considering over-excavation in strain-softening rock masses based on the generalized Zhang-Zhu strength criterion.A case study was conducted based on the Lianchengshan tunnel in China.The modified GRC was employed to investigate the ground-support behavior for different support schemes and to explore the applicability of the stress release measures.Combined with field tests,the proposed approach was validated.By comparing with GRCs proposed by previous work,the present modified GRC was proved to be superior to others.Parametric studies were conducted and it is found that over-excavation,for example,reserving a very large clearance between the surrounding rock and the support,is necessary to reduce ground pressure to a large extent.The yielding supports which can provide high support pressure during the process of deformation are highly recommended when tunneling in high geostress environment.However,if the initial geostress is not very high,it is not necessary to pursue unwarranted overexcavation since the ground pressure applied on the support is mainly the loosening stress when the deformation is large.Ample support stiffness should be provided in the process of deformation to prevent uncontrolled large deformation of surrounding rock. 展开更多
关键词 Ground response curve Large strain Over-excavation STRAIN-SOFTENING Soft rock tunnel
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An analytical solution for the undrained ground response to tunnelling considering the excavation-induced desaturation
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作者 Alexandros N.Nordas Linard Cantieni Georgios Anagnostou 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期1961-1972,共12页
When tunnelling through low-permeability saturated ground,the pore pressure decreases in the vicinity of the cavity.In certain instances of deep tunnels crossing weak rocks,the pore pressure may even become negative.A... When tunnelling through low-permeability saturated ground,the pore pressure decreases in the vicinity of the cavity.In certain instances of deep tunnels crossing weak rocks,the pore pressure may even become negative.All existing analytical solutions for the undrained ground response curve(GRC)in the literature assume that the ground fully retains its saturation,in which case the development of negative pore pressures has a stabilising effect e it results in increased effective stresses,and thus shearing resistance,which in turn leads to reduced deformations and plastification.In practice,however,negative pore pressures can induce partial or complete ground desaturation,which may even invalidate the premise of undrained conditions and lead to considerably increased deformations and plastification.In such cases,existing solutions are unsafe for design.The present paper aims to address this shortcoming,by presenting a novel analytical solution for the undrained GRC which incorporates the effect of the excavation-induced desaturation.The solution is derived under the assumption that the ground desaturates completely and immediately under negative pore pressures,which provides the upper bound of deformations and plastification for cases of partial desaturation.The rock is considered to be a linear elastic,brittle-plastic material,obeying a non-associated Mohr-Coulomb(MC)yield criterion.Nevertheless,the solution is also applicable to perfectly plastic rocks via a simple modification of the input parameters.Although the solution is in general semi-analytical,simple closed-form expressions are obtained in the special case of non-dilatant rocks.These expressions are also applicable to rocks exhibiting limited dilatancy,which is usually the case.An application example,based on the planned deep geological repository for radioactive waste in Switzerland,demonstrates the significant practical value and usefulness of the novel solution and underscores its necessity in cases where existing solutions that disregard desaturation are rendered thoroughly unsafe for design. 展开更多
关键词 Ground response curve(GRC) Undrained conditions Desaturation Suction Brittle softening
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Measuring Carbon Dioxide Sink of Betung Bamboo (Dendrocallamus asper (Schult f.) Backer ex Heyne) by Sinusoidal Curves Fitting on Its Daily Photosynthesis Light Response 被引量:1
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作者 Effendi Tri Bahtiar Naresworo Nugroho Anne Carolina Aditya Chandra Maulana 《Journal of Agricultural Science and Technology(B)》 2012年第7期780-788,共9页
Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditiona... Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditionally used by Indonesian people for construction material since a long time ago. Poaceae family commonly has better carbon sink ability than trees because of its Ca photosynthesis mechanisms, but bamboo sub-family (Bambusoideae) lacks the Ca photosynthetic pathway and anatomy. In the absence of this feature the maximum possible productivity of bamboos is unlikely to greatly exceed that of other bioenergy crops with C3 photosynthesis such as fast growing tree species. This research proposed a sinusoidal equation as a basic equation for plant's daily photosynthesis light response curve fitting. The sinusoidal equation was success for Betung bamboo's daily photosynthesis light response curve fitting (R2 〉 60%). It had similar result in estimating carbon sink (82.35 kg/clump/year) compared to those which calculated by annual increment (69.01-107.82 kg/clump/year). It is better to choose sinusoidal equation than quadratic or cubic Betung bamboo is a good choice to be planted in order to resist the global warming effect because it has superior carbon sink capability (82.35 kg/clump/year) than slow growing tree, and equal to fast growing tree species, besides many other advantages. 展开更多
关键词 Carbon sink Betung bamboo daily photosynthesis light response sinusoidal curve fitting.
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Hierarchical NiCo2O4 microspheres assembled by nanorods with p-type response for detection of triethylamine 被引量:1
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作者 Chen Yang Yongshan Xu +4 位作者 Lingli Zheng Yingqiang Zhao Wei Zheng Xianghong Liu Jun Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第8期2077-2082,共6页
The morphological and structural design provides an efficient protocol to optimize the performance of gas sensing materials.In this work,a gas sensor with high sensitivity for triethylamine(TEA)detection is developed ... The morphological and structural design provides an efficient protocol to optimize the performance of gas sensing materials.In this work,a gas sensor with high sensitivity for triethylamine(TEA)detection is developed based on p-type NiCo2 O4 hierarchical microspheres.The NiCo2 O4 microspheres,synthesized by a hydrothermal route,have a three-dimensional(3 D)urchin-like structure assembled by nanorod building blocks.The structure-property correlation has been investigated by powder X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscope,scanning electron microscope,N2 adsorption-desorption tests and comprehensive gas sensing experiments.The influence of calcination temperature on the morphological structure and sensing performances has been investigated.Results reveal that the material annealed at 300℃has a very large specific surface area of 125.27 m2/g,thereby demonstrating the best TEA sensing properties including high response and low limit of detection(145 ppb),good selectivity and stability.The further increase of the calcination temperature leads to the collapse of the 3 D hierarchical structure with significantly decreased surface area,which is found to decline the sensing performances.This work indicates the promise of ternary p-type metal oxide nanostructures for application in highly sensitive gas sensors. 展开更多
关键词 Microstructures Nico2O4 Metal oxide p-type response Gas sensor
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Dynamic Response of Curved Beam under Moving Load
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作者 单德山 李乔 蒋永林 《Journal of Modern Transportation》 1999年第2期163-172,共10页
In this paper an integral transform method is used to analyze the dynamic response of simple supported curved beam under single moving load with constant speed, and some parameters are defined. These parameters, such ... In this paper an integral transform method is used to analyze the dynamic response of simple supported curved beam under single moving load with constant speed, and some parameters are defined. These parameters, such as radius of curvature, ratio of stiffness, velocity, warping stiffness, which may influence the response, are also discussed. 展开更多
关键词 DYNAMIC response curved BEAM MOVING LOAD
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Magneto-Caloric Response of a Gd55Co25Al18Sn2 Bulk Metallic Glass
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作者 丁鼎 张一清 夏雷 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期80-83,共4页
The magneto-caloric effect (MCE) of a Gd55Co25Al18Sn2 bulk metallic glass (BMG) is investigated. The Gd55Co25AllsSn2 as-cast rod prepared by a water-cooled copper mold suction casting method exhibits typi- cal amo... The magneto-caloric effect (MCE) of a Gd55Co25Al18Sn2 bulk metallic glass (BMG) is investigated. The Gd55Co25AllsSn2 as-cast rod prepared by a water-cooled copper mold suction casting method exhibits typi- cal amorphous characteristics. The maximum magnetic entropy change (--ASPmeak) and the magnetic refrigerant capacity (Re) of the BMG under a field of 5 T are about 9.32 J.kg-X.K 1 and 832 J.kg-1, respectively, both of which are larger than the values of the Gd55 Co25A120 BMG. The mechanism for the improved MCE by minor Sn addition is studied and the field dependence of - magneto-caloric behaviors of Gd55Co25Al18Sn2 BMG ASPmeak is investigated for a better understanding on the 展开更多
关键词 BMG CO Magneto-Caloric response of a Gd Sn2 Bulk Metallic Glass AL
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QSAR study on the non-monotonic dose-response curve of PCBs in chicken embryo hepatocyte bioassay
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作者 YunSong Mu AiQian Zhang +2 位作者 ChangAn Gao SuFen Peng LianSheng Wang 《Science China Chemistry》 SCIE EI CAS 2009年第5期662-669,共8页
Endocrine disrupting chemicals (EDCs) in the natural environment exhibit a unique non-monotonic dose-response curve and it is impossible to select one simple index to characterize the bilogogical activity of these com... Endocrine disrupting chemicals (EDCs) in the natural environment exhibit a unique non-monotonic dose-response curve and it is impossible to select one simple index to characterize the bilogogical activity of these compounds. Quantitative structure-activity relationship (QSAR) study on non-monotonic dose-response curve has become a real challenge presently. In order to explore the possible mechanism for the non-monotonic dose-response curve of polychlorinated biphenyls congeners (PCBs) in chicken embryo hepatocyte bioassay, AM1 method of ChemOffice was adopted to calculate necessary structure descriptors for PCBs, while the interactions between PCBs and simulated AhR ligand binding domain (LBD) were analyzed by using FlexX in SYBYL7.0. Different binding modes for PCBs have been distinguished not only from aligned conformation but also from free binding energy. Some QSAR models were established separately for both low and high doses ranges, revealing that receptor binding may predominate in the interference of the physiological function of cytochrome P4501A-P4501A in the low doses range. But with the higher doses range, the EROD suppression might be related to acute toxicity owing to molecular polarity or distribution of charges and consequently damage structure and function of chicken embryo hepatocyte. 展开更多
关键词 POLYCHLORINATED BIPHENYLS CONGENERS (PCBs) non-monotonic DOSE-response curve quantitative STRUCTURE-ACTIVITY relationship (QSAR)
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A self-powered Ag/β-Ga_(2)O_(3) photodetector with broadband response from 200 to 980 nm based on the photovoltaic and pyro-phototronic effects 被引量:1
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作者 Xiongxin Luo Yueming Zhang +5 位作者 Lindong Liu Andy Berbille Kaixuan Wang Gaosi Han Laipan Zhu Zhong Lin Wang 《Journal of Materials Science & Technology》 2025年第3期125-134,共10页
β-Ga_(2)O_(3),as one of the important 4th generation semiconductors,is widely used in solar-blind ultraviolet(UV)detectors with a short detection range of 200-280 nm benefiting from its ultra-wide bandgap,strong radi... β-Ga_(2)O_(3),as one of the important 4th generation semiconductors,is widely used in solar-blind ultraviolet(UV)detectors with a short detection range of 200-280 nm benefiting from its ultra-wide bandgap,strong radiation resistance,and excellent chemical and thermal stabilities.Here,a self-powered photodetector(PD)based on an Ag/β-Ga_(2)O_(3) Schottky heterojunction was designed and fabricated.Through a subtle design of electrodes,the pyro-phototronic effect was discovered,which can be coupled to the common photovoltaic effect and further enhance the performance of the PD.Compared to traditional Ga_(2)O_(3)-based PD,the as-used PD exhibited a self-driving property and a broadband response beyond the bandgap lim-itations,ranging from 200 nm(deep UV)to 980 nm(infrared).Moreover,the photoresponse time was greatly shrunk owing to the coupling effect.Under laser irradiation,with a wavelength of 450 nm and a power density of 8 mW cm-2,the photocurrent could be improved by around 41 times compared with the sole photovoltaic effect.Besides,the performances of the Schottky PD were enhanced at both high and low temperatures.The device also possessed long-term working stability.This paper not only re-veals basic physics lying in the 4th generation semiconductor Ga_(2)O_(3) but also sheds light on the multi-encryption transmission of light information using this PD. 展开更多
关键词 PHOTODETECTOR β-Ga_(2)O_(3) Broadband response Pyro-phototronic effect SELF-POWERED
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Effect of Modulen vs budesonide on clinical response and mucosal healing in Crohn’s patients 被引量:1
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作者 Baruch Ovadia Eva Niv +3 位作者 Sara Stern Katie Elisabeth Mahajna Oren Gal Yael Kopelman 《World Journal of Gastroenterology》 2025年第5期84-93,共10页
BACKGROUND Mucosal healing has become an important goal of Crohn’s disease(CD)treat-ments.Modulen,enriched with transforming growth factor-beta 2,and budeso-nide are commonly accepted treatments for mild-moderate CD.... BACKGROUND Mucosal healing has become an important goal of Crohn’s disease(CD)treat-ments.Modulen,enriched with transforming growth factor-beta 2,and budeso-nide are commonly accepted treatments for mild-moderate CD.However,their effects on the small bowel(SB)mucosa remain underexplored.AIM To prospectively assess clinical and mucosal responses to Modulen vs budesonide in adults with CD,using SB capsule endoscopy.METHODS Thirty patients were divided into two groups:Modulen+home-based diet(21 patients)and budesonide(9 patients)for an eight-week intervention followed by four weeks of follow-up.Clinical,laboratory,and endoscopic responses were evaluated.The mucosal changes were assessed through SB capsule endoscopy.RESULTS Results indicated significant clinical improvement in the Modulen group with reduced CD activity index(P=0.041)and improved inflammatory bowel disease questionnaire score(P=0.016).Moreover,Modulen was associated with a signifi-cant SB mucosal improvement,evidenced by a decrease in Lewis score(P=0.027).No significant changes were observed in calprotectin or other laboratory parame-ters.Conversely,budesonide exhibited more modest clinical effects,but it improved calprotectin,hemoglobin,and C-reactive protein levels(P=0.051,P=0.014,and P=0.038,respectively).The capsule endoscopy did not reveal a significant mucosal response in the budesonide group.CONCLUSION Both interventions have a role in CD treatment.Yet,their effects differ and may complement each other:Modulen yields clinical and mucosal improvements,while budesonide primarily leads mainly to laboratory improvements. 展开更多
关键词 Crohn’s disease Modulen oral polymeric diet Transforming growth factor-beta 2 BUDESONIDE Mucosal healing Clinical response Capsule endoscopy Small bowel capsule
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2,3,5,4'-Tetrahydroxystilbene-2-O-β-glucoside Alleviates PCOS-like Characteristics by Upregulating The Expression of CYP19A1 in Granular Cells of Sinus Follicles to Inhibit Inflammatory Response
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作者 YAO Jian-Feng XU Bo +5 位作者 LIU Pin-Yue CHENG Di WEI Le PAN Xin-Yun MO Zhong-Cheng LI Ming 《生物化学与生物物理进展》 北大核心 2025年第3期735-750,共16页
Objective To investigate whether 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucoside(TSG)ameliorated polycystic ovary syndrome(PCOS)-like characteristics by inhibiting inflammation.Methods PCOS models were established ... Objective To investigate whether 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucoside(TSG)ameliorated polycystic ovary syndrome(PCOS)-like characteristics by inhibiting inflammation.Methods PCOS models were established by injecting subcutaneously with dehydroepiandrosterone into female Sprague-Dawley rats,followed by receiving intraperitoneal injection of TSG.The granular cells(GCs)KGN were transfected with small interfering RNAs(si-NC and si-CYP19A1).The cells were preincubated with lipopolysaccharide(LPS)and then treated with or without TSG.The estrous cycle was monitored using vaginal exfoliated cells.The morphology of ovarian follicles was analyzed by H&E staining.ELISA was used to analyze estradiol(E2),testosterone(T),follicle stimulating hormone(FSH),luteinizing hormone(LH),IL-6,TNF-α,AGEs,CRP and Omentin-1 levels in serum.Immunohistochemistry was performed to analyze PCNA and CYP19A1 expressions in the GCs of ovaries.Tunel staining was executed to detect the apoptosis of GCs.Quantitative polymerase chain reaction(qPCR)and Western blot were implemented to measure the expression of CYP19A1 in the ovaries and transfected cells.qPCR was used to analyze the expression of IL-6 and TNF-αin the transfected cells treated with LPS and TSG.Results The estrous cycles were restored in TSG group.Compared with model group,the sinus follicles were reduced and corpus luteums were increased in TSG group.TSG group showed increased E2,and decreased T and LH,compared with model group.Pro-inflammatory factors(IL-6,TNF-α,CRP and AGEs)were decreased,and anti-inflammatory factor(Omentin-1)was increased in TSG group compared with those in model group.TSG could partially inhibit decrease of PNCA-positive GCs and increase of Tunel-positive GCs caused by PCOS.The CYP19A1 expression of GCs in TSG group was upregulated compared with model group.The expressions of IL-6 and TNFαin si-CYP19A1 cells were increased compared with si-NC cells.Compared with cells(si-NC and si-CYP19A1)treated without LPS,the expressions of IL-6 and TNF-αcells were increased,and the expression of CYP19A1 was downregulated in LPS-preincubated cells.Compared with cells treated with LPS,the expression of IL-6 and TNF-αwere decreased,and the expression of CYP19A1 was increased in cells treated with LPS and TSG.Compared with si-NC cells treated with LPS and TSG,the expressions of IL-6 and TNF-αcells were increased in the si-CYP19A1 cells treated with LPS and TSG.Conclusion TSG could alleviate PCOS-like characteristics by increasing the expression of CYP19A1 in GCs to inhibit inflammatory response. 展开更多
关键词 2 3 5 4'-tetrahydroxystilbene-2-O-β-glucoside granular cells CYP19A1 polycystic ovary syndrome inflammatory response
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Parameter influence analysis and optimization of wheel–rail creepage characteristics in high-speed railway curves
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作者 Bolun An Jiapeng Liu +3 位作者 Guang Yang Feng shou Liu Tong Shi Ming Zhai 《Railway Sciences》 2025年第1期37-51,共15页
Purpose–To investigate the influence of vehicle operation speed,curve geometry parameters and rail profile parameters on wheel–rail creepage in high-speed railway curves and propose a multi-parameter coordinated opt... Purpose–To investigate the influence of vehicle operation speed,curve geometry parameters and rail profile parameters on wheel–rail creepage in high-speed railway curves and propose a multi-parameter coordinated optimization strategy to reduce wheel–rail contact fatigue damage.Design/methodology/approach–Taking a small-radius curve of a high-speed railway as the research object,field measurements were conducted to obtain track parameters and wheel–rail profiles.A coupled vehicle-track dynamics model was established.Multiple numerical experiments were designed using the Latin Hypercube Sampling method to extract wheel-rail creepage indicators and construct a parameter-creepage response surface model.Findings–Key service parameters affecting wheel–rail creepage were identified,including the matching relationship between curve geometry and vehicle speed and rail profile parameters.The influence patterns of various parameters on wheel–rail creepage were revealed through response surface analysis,leading to the establishment of parameter optimization criteria.Originality/value–This study presents the systematic investigation of wheel–rail creepage characteristics under multi-parameter coupling in high-speed railway curves.A response surface-based parameter-creepage relationship model was established,and a multi-parameter coordinated optimization strategy was proposed.The research findings provide theoretical guidance for controlling wheel–rail contact fatigue damage and optimizing wheel–rail profiles in high-speed railway curves. 展开更多
关键词 High-speed railway curve track Wheel-rail creepage Parameter analysis response surface methodology Optimization design
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