期刊文献+
共找到114,364篇文章
< 1 2 250 >
每页显示 20 50 100
Experimental research on the mixed sand ratio and initial dry density of weathered sand improved expansive soil free load swelling rate
1
作者 Yang Jun Yang Zhi +2 位作者 Zhang Guodong Tang Yunwei Chen Hongping 《Engineering Sciences》 EI 2014年第3期77-82,共6页
In this paper, through the indoor free load swelling rate test, expansive soil in a section of a first- class highway reconstruction project in Yichang City was studied. It emphatically analyzed the interrelations amo... In this paper, through the indoor free load swelling rate test, expansive soil in a section of a first- class highway reconstruction project in Yichang City was studied. It emphatically analyzed the interrelations among free load swelling rate, non-load time, the proportion of mixed sand and initial dry density. Experimen- tal studies have shown that: Free load swelling deformation is mainly divided into three stages of rapid expan- sion, slow expansion and final stability; when the initial dry density is constant, free load swelling rate of the weathered sand modified soil will reduce rapidly before they slow down with the increase of sand proportion, and weathered sand modified soil free load swelling rate is not sensitive to the large amount of sand mixed; in the same mixed sand ratio, weathered sand modified soil free load swelling rate increases rapidly with the in- crease of initial dry density, there is a good linear correlation between them. To take appropriate control of the initial dry density during the expansive soil subgrade construction helps to reduce its swelling deformation and ensures the stability of the embankment. 展开更多
关键词 expansive soil weathered SAND INITIAL dry density MIXING SAND ratio free LOAD SWELLING rate
下载PDF
Effect of dry density on the liquefaction behaviour of Quaternary silt 被引量:2
2
作者 ZHANG Chong-lei JIANG Guan-lu +2 位作者 SU Li-jun Liu Wei-ming ZHOU Gong-dan 《Journal of Mountain Science》 SCIE CSCD 2018年第7期1597-1614,共18页
Quaternary silt is widely distributed in China and easily liquefies during earthquakes. To identify the influence of the dry density on the liquefaction behaviour of Quaternary silt, 40 cyclic triaxial liquefaction te... Quaternary silt is widely distributed in China and easily liquefies during earthquakes. To identify the influence of the dry density on the liquefaction behaviour of Quaternary silt, 40 cyclic triaxial liquefaction tests were performed on loose silt(dry density rd=1.460 g/cm^3) and dense silt(rd=1.586 g/cm^3) under different cyclic stress ratios(CSRs) to obtain liquefaction assessment criteria, determine the liquefaction resistance, improve the excess pore water pressure(EPWP) growth model and clarify the relationship between the shear modulus and damping ratio. The results indicate that the initial liquefaction assessment criteria for the loose and dense silts are a double-amplitude axial strain of 5% and an EPWP ratio of 1. The increase in the anti-liquefaction ability for the dense silt is more significant under lower confining pressures. The CSR of loose silt falls well within the results of the sandy silt and Fraser River silt, and the dense silt exhibits a higher liquefaction resistance than the sand-silt mixture. The relationships between the CSR and loading cycles were obtained at a failure strain of 1%. The EPWP development in the dense and loose silts complies with the "fast-stable" and "fast-gentle-sharp" growth modes, respectively. The power function model can effectively describe the EPWP growth characteristics of the dense silt. Finally, based on the liquefaction behaviour of silt, a suggestion for reinforcing silt slopes or foundations is proposed. 展开更多
关键词 淤泥 液化 密度 干燥 行为 四级 评价标准 CSR
原文传递
Influence of Dry Density on Soil-Water Retention Curve of Unsaturated Soils and Its Mechanism Based on Mercury Intrusion Porosimetry
3
作者 李博 陈宇龙 《Transactions of Tianjin University》 EI CAS 2016年第3期268-272,共5页
The soil-water retention curve(SWRC)can be used to evaluate the ability of unsaturated soils to attract water at various water contents and suctions. In this study, drying SWRCs for a kind of sandy soil were obtained ... The soil-water retention curve(SWRC)can be used to evaluate the ability of unsaturated soils to attract water at various water contents and suctions. In this study, drying SWRCs for a kind of sandy soil were obtained in the laboratory by using self-modified SWRC apparatus. In addition, the porosity and the pore size distribution of the samples were investigated by a mercury porosimetry test in order to analyze the effect of dry density. Results showed that the soil-water retention of the soil specimens was strongly dependent on the dry density. Under zero suction, soil specimens with a higher dry density exhibited lower initial volumetric water content. The higher the dry density of soil, the more slowly the volumetric water content decreased with the increase of suction. There was a general and consistent trend for a soil specimen to possess a larger air-entry value and residual suction, while smaller slope of SWRC when it had a higher density. This was probably attributed to the presence of smaller interconnected pores in the soil specimen with a higher dry density. The proportion of large diameter pores decreased in comparison to pores with small diameters in the soil tested. The measured total pore volume of the soil specimen, which had a larger dry density, was lower than that of the relatively loose specimens. 展开更多
关键词 土壤水分特征曲线 土壤干密度 非饱和土 压汞法 土壤样品 土壤含水量 体积含水量 机制
下载PDF
Increasing the appropriate seedling density for higher yield in dry direct-seeded rice sown by a multifunctional seeder after wheatstraw return
4
作者 TIAN Jin-yu LI Shao-ping +8 位作者 CHENG Shuang LIU Qiu-yuan ZHOU Lei TAO Yu XING Zhi-peng HU Ya-jie GUO Bao-wei WEI Hai-yan ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第2期400-416,共17页
Dry direct-seeded rice(DDR) sown using a multifunctional seeder that performs synchronous rotary tillage and sowing has received increased attention because it is highly efficient,relatively cheap,and environmentally ... Dry direct-seeded rice(DDR) sown using a multifunctional seeder that performs synchronous rotary tillage and sowing has received increased attention because it is highly efficient,relatively cheap,and environmentally friendly.However,this method of rice production may produce lower yields in a rice–wheat rotation system because of its poor seedling establishment.To address this problem,we performed field experiments to determine the rice yield at five seedling density levels(B1,B2,B3,B4,and B5=100,190,280,370,and 460 seedlings m-2,respectively) and clarify the physiological basis of yield formation.We selected a representative high-quality rice variety and a multifunctional seeder that used in a typical rice–wheat rotation area in 2016 and 2018.The proportion of main stem panicle increased with increasing seedling density.There was a parabolic relationship between yield and seedling density,and the maximum yield(9.34-9.47 t ha-1) was obtained under B3.The maximum yield was associated with a higher total spikelet number m-2 and greater biomass accumulation from heading to maturity.The higher total spikelet number m-2 under B3 was attributed to an increase in panicle number m-2 compared with B1 and B2.Although the panicle numbers also increased under B4 and B5,these increases were insufficient to compensate for the reduced spikelet numbers per panicle.Lower biomass,smaller leaf area,and lower N uptake per plant from the stem elongation stage to the heading stage were partially responsible for the smaller panicle size at higher seedling density levels such as B5.The higher biomass accumulation under B3 was ascribed to the increases in the photosynthetic rate of the top three leaves m-2 of land,crop growth rate,net assimilation rate,and leaf area index.Furthermore,the B3 rice population was marked by a higher grain–leaf ratio,as well as a lower export ratio and transport ratio of biomass per stem-sheath.A quadratic function predicted that 260-290 seedlings m-2 is the optimum seedling density for achieving maximum yield.Together,these results suggested that appropriately increasing the seedling density,and thereby increasing the proportion of panicles formed by the main stem,is an effective approach for obtaining a higher yield in DDR sown using a multifunctional seeder in a rice–wheat rotation system. 展开更多
关键词 seedling density dry direct-seeded rice sown by a multifunctional seeder rice–wheat rotation system yield biomass photosynthetic capacity
下载PDF
Asymmetric Drying and Wetting Trends in Eastern and Western China 被引量:1
5
作者 Wen WU Fei JI +1 位作者 Shujuan HU Yongli HE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期221-232,共12页
As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous ... As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous research has mainly focused on the long-term linear changes of dry/wet conditions, while the detection and evolution of the non-linear trends related to dry/wet changes have received less attention. The non-linear trends of the annual aridity index, obtained by the Ensemble Empirical Mode Decomposition(EEMD) method, reveal that changes in dry/wet conditions in China are asymmetric and can be characterized by contrasting features in both time and space in China. Spatially, most areas in western China have experienced transitions from drying to wetting, while opposite changes have occurred in most areas of eastern China. Temporally, the transitions occurred earlier in western China compared to eastern China. Research into the asymmetric spatial characteristics of dry/wet conditions compensates for the inadequacies of previous studies, which focused solely on temporal evolution;at the same time, it remedies the inadequacies of traditional research on linear trends over centennial timescales. Analyzing the non-linear trend also provides for a more comprehensive understanding of the drying/wetting changes in China. 展开更多
关键词 aridity index EEMD dry/wet conditions asymmetric evolution
下载PDF
Anthropogenic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s 被引量:1
6
作者 Qin SU Buwen DONG +1 位作者 Fangxing TIAN Nicholas P.KLINGAMAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期233-246,共14页
The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characteriz... The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the present day(PD,1994–2011) is double that in the early period(EP, 1964–81);the duration of HDEs increases by 60%. Climate experiments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthropogenic forcing to HDE decadal changes over China. Anthropogenic forcing changes can explain 60%–70% of the observed decadal changes,suggesting an important anthropogenic influence on HDE changes over China across the mid-1990s. Single-forcing experiments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthropogenic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in response to anthropogenic forcing are mainly due to the response of climatological mean surface air temperatures. The contributions from changes in variability and changes in climatological mean soil moisture and evapotranspiration are relatively small. The physical processes associated with the response of HDEs to GHG and AA changes are also revealed. 展开更多
关键词 concurrent hot and dry events decadal variation greenhouse gases aerosol emissions
下载PDF
Effect of different drying methods on the amino acids,α-dicarbonyls and volatile compounds of rape bee pollen 被引量:1
7
作者 Yanxiang Bi Jiabao Ni +6 位作者 Xiaofeng Xue Zidan Zhou Wenli Tian Valérie Orsat Sha Yan Wenjun Peng Xiaoming Fang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期517-527,共11页
The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed ... The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were determined.The results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest loss.Glucosone was the dominantα-DCs in RBP and the highest loss was observed after PVD.Aldehydes were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying methods.Comprehensively,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process. 展开更多
关键词 dryING Bee pollen Free amino acids α-Dicarbonyl compounds Volatile compounds
下载PDF
High energy density in ultra-thick and flexible electrodes enabled by designed conductive agent/binder composite
8
作者 Xiaoyu Shen Hailong Yu +6 位作者 Liubin Ben Wenwu Zhao Qiyu Wang Guanjun Cen Ronghan Qiao Yida Wu Xuejie Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期133-143,I0005,共12页
Thick electrodes can increase incorporation of active electrode materials by diminishing the proportion of inactive constituents,improving the overall energy density of batteries.However,thick electrodes fabricated us... Thick electrodes can increase incorporation of active electrode materials by diminishing the proportion of inactive constituents,improving the overall energy density of batteries.However,thick electrodes fabricated using the conventional slurry casting approach frequently exhibit an exacerbated accumulation of carbon additives and binders on their surfaces,invariably leading to compromised electrochemical properties.In this study,we introduce a designed conductive agent/binder composite synthesized from carbon nanotube and polytetrafluoroethylene.This agent/binder composite facilitates production of dry-process-prepared ultra-thick electrodes endowed with a three-dimensional and uniformly distributed percolative architecture,ensuring superior electronic conductivity and remarkable mechanical resilience.Using this approach,ultra-thick LiCoO_(2)(LCO) electrodes demonstrated superior cycling performance and rate capabilities,registering an impressive loading capacity of up to 101.4 mg/cm^(2),signifying a 242% increase in battery energy density.In another analytical endeavor,time-of-flight secondary ion mass spectroscopy was used to clarify the distribution of cathode electrolyte interphase(CEI) in cycled LCO electrodes.The results provide unprecedented evidence explaining the intricate correlation between CEI generation and carbon distribution,highlighting the intrinsic advantages of the proposed dry-process approach in fine-tu ning the CEI,with excellent cycling performance in batteries equipped with ultra-thick electrodes. 展开更多
关键词 Conductive agent/binder composite dry process Ultra-thick electrodes High energy density CEI reconstruction ToF-SIMS
下载PDF
Wearable multilead ECG sensing systems using on-skin stretchable and breathable dry adhesives
9
作者 Yingxi Xie Longsheng Lu +1 位作者 Wentao Wang Huan Ma 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第2期167-180,共14页
Electrocardiogram(ECG)monitoring is used to diagnose cardiovascular diseases,for which wearable electronics have attracted much attention due to their lightweight,comfort,and long-term use.This study developed a weara... Electrocardiogram(ECG)monitoring is used to diagnose cardiovascular diseases,for which wearable electronics have attracted much attention due to their lightweight,comfort,and long-term use.This study developed a wearablemultilead ECG sensing system with on-skin stretchable and conductive silver(Ag)-coated fiber/silicone(AgCF-S)dry adhesives.Tangential and normal adhesion to pigskin(0.43 and 0.20 N/cm2,respectively)was optimized by the active control of fiber density and mixing ratio,resulting in close contact in the electrode–skin interface.The breathableAgCF-S dry electrodewas nonallergenic after continuous fit for 24 h and can be reused/cleaned(>100 times)without loss of adhesion.The AgCF encapsulated inside silicone elastomers was overlapped to construct a dynamic network under repeated stretching(10%strain)and bending(90°)deformations,enabling small intrinsic impedance(0.3,0.1 Hz)and contact impedance variation(0.7 k)in high-frequency vibration(70 Hz).All hard/soft modules of the multilead ECG system were integrated into lightweight clothing and equipped with wireless transmission for signal visualization.By synchronous acquisition of I–III,aVR,aVL,aVF,and V4 lead data,the multilead ECG sensing system was suitable for various scenarios,such as exercise,rest,and sleep,with extremely high signal-to-noise ratios. 展开更多
关键词 Multilead electrocardiogram dry electrodes Wearable electronics Wireless transmission
下载PDF
Electron density measurement by the three boundary channels of HCOOH laser interferometer on the HL-3 tokamak
10
作者 牟俊任 李永高 +5 位作者 李远 王再宏 丁宝钢 王浩西 易江 石中兵 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期88-93,共6页
Far-infrared(FIR)interferometer is widely used to measure the electron density in the magnetically confined fusion plasma devices.A new FIR laser interferometer with a total of 13 channels(8 horizontal channels and 5 ... Far-infrared(FIR)interferometer is widely used to measure the electron density in the magnetically confined fusion plasma devices.A new FIR laser interferometer with a total of 13 channels(8 horizontal channels and 5 oblique channels)is under development on the HL-3tokamak by using the formic-acid laser(HCOOH,f=694 GHz).In order to investigate the boundary electron density activity during the divertor discharge,three horizontal interferometry channels located at Z=-97,-76,76.5 cm have been successfully developed on HL-3 in 2023,and put into operation in recent experimental campaign,with a time resolution of<1.0μs and lineintegrated electron density resolution of~7.0×10^(16) m^(-2).This paper mainly focuses on the optical design of the three-channel interferometry system,as well as optical elements and recent experimental result on HL-3. 展开更多
关键词 electron density INTERFEROMETER HL-3
下载PDF
Evolutionary history shapes variation of wood density of tree species across the world
11
作者 Fangbing Li Hong Qian +7 位作者 Jordi Sardans Dzhamal Y.Amishev Zixuan Wang Changyue Zhang Tonggui Wu Xiaoniu Xu Xiao Tao Xingzhao Huang 《Plant Diversity》 SCIE CAS CSCD 2024年第3期283-293,共11页
The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been tested.Using a comprehensive global dataset including 27,297 m... The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been tested.Using a comprehensive global dataset including 27,297 measurements of wood density from 2621 tree species worldwide,we test the hypothesis that the legacy of evolutionary history plays an important role in driving the variation of wood density among tree species.We assessed phylogenetic signal in different taxonomic(e.g.,angiosperms and gymnosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phylogenetic patterns of wood density,and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary history(i.e.,phylogenetic relatedness among species and lineages)in driving global wood density variation.We found that wood density displayed a significant phylogenetic signal.Wood density differed among different biomes and climatic zones,with higher mean values of wood density in relatively drier regions(highest in subtropical desert).Our study revealed that at a global scale,for angiosperms and gymnosperms combined,phylogeny and species(representing the variance explained by taxonomy and not direct explained by long-term evolution process)explained 84.3%and 7.7%of total wood density variation,respectively,whereas current environment explained 2.7%of total wood density variation when phylogeny and species were taken into account.When angiosperms and gymnosperms were considered separately,the three proportions of explained variation are,respectively,84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for gymnosperms.Our study shows that evolutionary history outpaced current environmental factors in shaping global variation in wood density. 展开更多
关键词 Wood density PHYLOGENY ANGIOSPERMS GYMNOSPERMS Climate factors Biophysical parameters
下载PDF
Evaluation of dry eye disease symptomatology and mental health status among patients with different COVID-19 statuses
12
作者 Fang Ruan Wen-Jun Kong +4 位作者 Qian Fan Hong-Wei Dong Wei Zhang Wen-Bin Wei Ying Jie 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期822-830,共9页
AIM:To evaluate dry eye disease(DED)symptomatology and mental health status in different COVID-19 patients.METHODS:A cross-sectional observational design was used.Totally 123 eligible adults(46.34%of men,age range,18-... AIM:To evaluate dry eye disease(DED)symptomatology and mental health status in different COVID-19 patients.METHODS:A cross-sectional observational design was used.Totally 123 eligible adults(46.34%of men,age range,18-59y)with COVID-19 included in the study from August to November,2022.Ocular Surface Disease Index(OSDI),Five-item Dry Eye Questionnaire(DEQ-5),Hospital Anxiety and Depression Scale(HADS),and Pittsburgh Sleep Quality Index(PSQI)were used in this study.RESULTS:OSDI scores were 6.82(1.25,15.91)in asymptomatic carriers,7.35(2.50,18.38)in mild cases,and 16.67(4.43,28.04)in recurrent cases,with 30.00%,35.56%,and 57.89%,respectively evaluated as having DED symptoms(χ2=7.049,P=0.029).DEQ-5 score varied from 2.00(0,6.00)in asymptomatic carriers,3.00(0,8.00)in mild cases,and 8.00(5.00,10.00)in recurrent cases,with 27.50%,33.33%,and 55.26%,respectively assessed as having DED symptoms(χ2=8.532,P=0.014).The prevalence of clinical anxiety(50.00%)and depression(47.37%)symptoms were also significantly higher in patients with recurrent infection(χ2=24.541,P<0.001;χ2=30.871,P<0.001).Recurrent infection was a risk factor for high OSDI scores[odds ratio,2.562;95%confidence interval(CI),1.631-7.979;P=0.033]and DEQ-5 scores(odds ratio,3.353;95%CI,1.038-8.834;P=0.043),whereas having a fixed occupation was a protective factor for OSDI scores(odds ratio,0.088;95%CI,0.022-0.360;P=0.001)and DEQ-5 scores(odds ratio,0.126;95%CI,0.039-0.405;P=0.001).CONCLUSION:Patients with recurrent COVID-19 have more severe symptoms of DED,anxiety,and depression. 展开更多
关键词 COVID-19 dry eye disease recurrent infection mental health
原文传递
Temperature dependence of mechanical properties and damage evolution of hot dry rocks under rapid cooling
13
作者 Longjun Dong Yihan Zhang +2 位作者 Lichang Wang Lu Wang Shen Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期645-660,共16页
Understanding the differences in mechanical properties and damage characteristics of granitoid under high temperatures is crucial for exploring deep geothermal resources.This study analyzes the evolution of the acoust... Understanding the differences in mechanical properties and damage characteristics of granitoid under high temperatures is crucial for exploring deep geothermal resources.This study analyzes the evolution of the acoustic emission(AE)characteristics and mechanical parameters of granodiorite and granite after heating and water cooling by uniaxial compression and variable-angle shear tests under different temperature gradients.We identify their changes in mesostructure and mineral composition with electron probe microanalysis and scanning electron microscopy.Results show that these two hot dry rocks have similar diagenetic minerals and microstructure,but show significantly different mechanical and acoustic characteristics,and even opposing evolution trends in a certain temperature range.At the temperatures ranging from 100℃to 500℃,the compressive and shear mechanical properties of granodiorite switch repeatedly between weakening and strengthening,and those of granite show a continuous weakening trend.At 600℃,both rocks exhibit a deterioration of mechanical properties.The damage mode of granite is characterized by initiating at low stress,exponential evolutionary activity,and intensified energy release.In contrast,granodiorite exhibits the characteristics of initiating at high stress,volatile evolutionary activity,and intermittent energy release,due to its more stable microstructure and fewer thermal defects compared to granite.As the temperature increases,the initiation and propagation of secondary cracks in granodiorite are suppressed to a certain extent,and the seismicity and brittleness are enhanced.The subtle differences in grain size,microscopic heterogeneity,and mineral composition of the two hot dry rocks determine the different acoustic-mechanical characteristics under heating and cooling,and the evolution trends with temperature.These findings are of great significance for the scientific and efficient construction of rock mass engineering by rationally utilizing different rock strata properties. 展开更多
关键词 Hot dry rock Acoustic emission Mechanical properties High temperature DAMAGE
下载PDF
Dry Breeding and Dry Planting Techniques for Indica Hybrid Rice in Karst Mountain Areas of Gejiu City
14
作者 Guifen WANG Wei SHI 《Plant Diseases and Pests》 2024年第2期34-36,共3页
Based on the arable land situation in Gejiu City,upland dry planting of indica hybrid rice is being expanded in Karst mountain areas with a rainfall of over 1400 mm and an altitude of 1100-1600 m to develop grain prod... Based on the arable land situation in Gejiu City,upland dry planting of indica hybrid rice is being expanded in Karst mountain areas with a rainfall of over 1400 mm and an altitude of 1100-1600 m to develop grain production.This paper gives a specific description of hybrid rice upland dry seedling technology,upland transplanting technology,fertilization technology,field management,weed prevention and control technology,and disease and pest control. 展开更多
关键词 Karst mountain area Hybrid rice dry breeding dry planting
下载PDF
Wetting alternating with partial drying during grain filling increases lysine biosynthesis in inferior rice grain
15
作者 Yi Jiang Wenli Tao +2 位作者 Weiyang Zhang Zhiqin Wang Jianchang Yang 《The Crop Journal》 SCIE CSCD 2024年第1期262-270,共9页
Lysine content is a criterion of the nutritional quality of rice.Understanding the process of lysine biosynthesis in early-flowering superior grain(SG)and late-flowering inferior grain(IG)of rice would advance breedin... Lysine content is a criterion of the nutritional quality of rice.Understanding the process of lysine biosynthesis in early-flowering superior grain(SG)and late-flowering inferior grain(IG)of rice would advance breeding and cultivation to improve nutritional quality.However,little information is available on differences in lysine anabolism between SG and IG and the underlying mechanism,and whether and how irrigation regimes affect lysine anabolism in these grains.A japonica rice cultivar was grown in the field and two irrigation regimes,continuous flooding(CF)and wetting alternating with partial drying(WAPD),were imposed from heading to the mature stage.Lysine content and activities of key enzymes of lysine biosynthesis,and levels of brassinosteroids(BRs)were lower in the IG than in the SG at the early grainfilling stage but higher at middle and late grain-filling stages.WAPD increased activities of these key enzymes,BR levels,and contents of lysine and total amino acids in IG,but not SG relative to CF.Application of 2,4-epibrassinolide to rice panicles in CF during early grain filling reproduced the effects of WAPD,but neither treatment altered the activities of enzymes responsible for lysine catabolism in either SG or IG.WAPD and elevated BR levels during grain filling increased lysine biosynthesis in IG.Improvement in lysine biosynthesis in rice should focus on IG. 展开更多
关键词 BRASSINOSTEROIDS Inferior grain Lysine biosynthesis Rice Wetting alternating with partial drying
下载PDF
Dry eye rate and its relationship with disease stage in patients with primary hypertension:a cross-sectional study in Vietnam
16
作者 Tran Tat Thang Pham Hong Phuong +7 位作者 Nguyen Sa Huynh Nguyen Trung Kien NguyenDuy Toan Nguyen Thi Thu Ha Le Ha Khoa Nguyen Huu Dung Thai Doan Thang Le Viet Thang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期653-658,共6页
AIM:To determine the dry eye(DE)rate and its relationship with disease stage in patients with primary hypertension.METHODS:A cross-sectional study included 432 patients with primary hypertension(with an equal number o... AIM:To determine the dry eye(DE)rate and its relationship with disease stage in patients with primary hypertension.METHODS:A cross-sectional study included 432 patients with primary hypertension(with an equal number of patients in each group:144 in stage Ⅰ,Ⅱ,and Ⅲ hypertension)and 144 healthy subjects as a control group.The Ocular Surface Disease Index(OSDI)and Schirmer Ⅰ test without anesthetics were conducted on all 576 subjects.Subjects with OSDI scores<13 and Schirmer Ⅰ values equal to or under 10 mm were diagnosed with DE.RESULTS:The ratio of DE in hypertension patients was higher than in the control group(41.7%versus 18.8%;P<0.001).The proportion of patients with DE increased gradually according to the hypertension stage:27.1% in stage Ⅰ,40.3% in stage Ⅱ,and 57.6% in stage Ⅲ,P<0.001.Age,duration of hypertension,plasma urea,creatinine,and high-sensitivity C-reactive protein(CRP-hs)levels in hypertension patients with DE were higher than those without DE,P<0.001.Advanced age,a long duration of hypertension,diabetes mellitus,elevated plasma creatinine,and CRP-hs levels were independent factors associated with DE in primary hypertension patients,P<0.001.CONCLUSION:DE is a common disorder associated with advanced age,a long duration of hypertension,diabetes mellitus,elevated plasma CRP-hs,and creatinine levels in patients with primary hypertension. 展开更多
关键词 primary hypertension dry eye stage of hypertension plasma creatinine
原文传递
A detailed rock density model of the Hong Kong territories
17
作者 Albertini Nsiah Ababio Robert Tenzer 《Geodesy and Geodynamics》 EI CSCD 2024年第1期75-81,共7页
We used the geological map and published rock density measurements to compile the digital rock density model for the Hong Kong territories.We then estimated the average density for the whole territory.According to our... We used the geological map and published rock density measurements to compile the digital rock density model for the Hong Kong territories.We then estimated the average density for the whole territory.According to our result,the rock density values in Hong Kong vary from 2101 to 2681 kg·m^(-3).These density values are typically smaller than the average density of 2670 kg·m^(-3),often adopted to represent the average density of the upper continental crust in physical geodesy and gravimetric geophysics applications.This finding reflects that the geological configuration in Hong Kong is mainly formed by light volcanic formations and lava flows with overlying sedimentary deposits at many locations,while the percentage of heavier metamorphic rocks is very low(less than 1%).This product will improve the accuracy of a detailed geoid model and orthometric heights. 展开更多
关键词 density model Rock types Gravimetric modeling Hong Kong
原文传递
Local thermal conductivity of inhomogeneous nano-fluidic films:A density functional theory perspective
18
作者 孙宗利 康艳霜 康艳梅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期594-603,共10页
Combining the mean field Pozhar-Gubbins(PG)theory and the weighted density approximation,a novel method for local thermal conductivity of inhomogeneous fluids is proposed.The correlation effect that is beyond the mean... Combining the mean field Pozhar-Gubbins(PG)theory and the weighted density approximation,a novel method for local thermal conductivity of inhomogeneous fluids is proposed.The correlation effect that is beyond the mean field treatment is taken into account by the simulation-based empirical correlations.The application of this method to confined argon in slit pore shows that its prediction agrees well with the simulation results,and that it performs better than the original PG theory as well as the local averaged density model(LADM).In its further application to the nano-fluidic films,the influences of fluid parameters and pore parameters on the thermal conductivity are calculated and investigated.It is found that both the local thermal conductivity and the overall thermal conductivity can be significantly modulated by these parameters.Specifically,in the supercritical states,the thermal conductivity of the confined fluid shows positive correlation to the bulk density as well as the temperature.However,when the bulk density is small,the thermal conductivity exhibits a decrease-increase transition as the temperature is increased.This is also the case in which the temperature is low.In fact,the decrease-increase transition in both the small-bulk-density and low-temperature cases arises from the capillary condensation in the pore.Furthermore,smaller pore width and/or stronger adsorption potential can raise the critical temperature for condensation,and then are beneficial to the enhancement of the thermal conductivity.These modulation behaviors of the local thermal conductivity lead immediately to the significant difference of the overall thermal conductivity in different phase regions. 展开更多
关键词 thermal conductivity nano-fluidic films density functional theory
原文传递
Density functional theory study of B- and Si-doped carbons and their adsorption interactions with sulfur compounds
19
作者 Peng Guo Hong Zhang +1 位作者 Shuliang Dong Libao An 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期195-208,共14页
Understanding the adsorption interactions between carbon materials and sulfur compounds has far-reaching impacts,in addition to their well-known important role in energy storage and conversion,such as lithium-ion batt... Understanding the adsorption interactions between carbon materials and sulfur compounds has far-reaching impacts,in addition to their well-known important role in energy storage and conversion,such as lithium-ion batteries.In this paper,properties of intrinsic B or Si single-atom doped,and B-Si codoped graphene(GR)and graphdiyne(GDY)were investigated by using density functional theory-based calculations,in which the optimal doping configurations were explored for potential applications in adsorbing sulfur compounds.Results showed that both B or Si single-atom doping and B-Si codoping could substantially enhance the electron transport properties of GR and GDY,improving their surface activity.Notably,B and Si atoms displayed synergistic effects for the codoped configurations,where B-Si codoped GR/GDY exhibited much better performance in the adsorption of sulfurcontaining chemicals than single-atom doped systems.In addition,results demonstrated that,after B-Si codoping,the adsorption energy and charge transfer amounts of GDY with sulfur compounds were much larger than those of GR,indicating that B-Si codoped GDY might be a favorable material for more effectively interacting with sulfur reagents. 展开更多
关键词 ADSORPTION density functional theory DOPING graphdiyne GRAPHENE sulfur compounds
下载PDF
Dual‑Atom Nanozyme Eye Drops Attenuate Inflammation and Break the Vicious Cycle in Dry Eye Disease
20
作者 Dandan Chu Mengyang Zhao +8 位作者 Shisong Rong Wonho Jhe Xiaolu Cai Yi Xiao Wei Zhang Xingchen Geng Zhanrong Li Xingcai Zhang Jingguo Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期439-457,共19页
Dry eye disease(DED)is a major ocular pathology worldwide,causing serious ocular discomfort and even visual impairment.The incidence of DED is gradually increasing with the highfrequency use of electronic products.Alt... Dry eye disease(DED)is a major ocular pathology worldwide,causing serious ocular discomfort and even visual impairment.The incidence of DED is gradually increasing with the highfrequency use of electronic products.Although inflammation is core cause of the DED vicious cycle,reactive oxygen species(ROS)play a pivotal role in the vicious cycle by regulating inflammation from upstream.Therefore,current therapies merely targeting inflammation show the failure of DED treatment.Here,a novel dual-atom nanozymes(DAN)-based eye drops are developed.The antioxidative DAN is successfully prepared by embedding Fe and Mn bimetallic single-atoms in N-doped carbon material and modifying it with a hydrophilic polymer.The in vitro and in vivo results demonstrate the DAN is endowed with superior biological activity in scavenging excessive ROS,inhibiting NLRP3 inflammasome activation,decreasing proinflammatory cytokines expression,and suppressing cell apoptosis.Consequently,the DAN effectively alleviate ocular inflammation,promote corneal epithelial repair,recover goblet cell density and tear secretion,thus breaking the DED vicious cycle.Our findings open an avenue to make the DAN as an intervention form to DED and ROSmediated inflammatory diseases. 展开更多
关键词 dry eye disease DAN Dual-atom nanozyme Vicious cycle NLRP3 inflammasome NANOMEDICINE
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部