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Effects of gravel on the water absorption characteristics and hydraulic parameters of stony soil

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Journal of Arid Land 2024年第7期16卷 895-909页

作者： ma yan WANG Youqi ma Chengfeng YUAN Cheng BAI Yiru Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China Ningxia UniversityYinchuan 750021China School of Geography and Planning Ningxia UniversityYinchuan 750021China School of Ecology and Environment Ningxia UniversityYinchuan 750021China

The eastern foothills of the Helan Mountains in China are a typical mountainous region of soil and gravel,where gravel could affect the water movement process in the *** study focused on the effects of different gravel contents on the water absorption characteristics and hydraulic parameters of stony *** stony soil samples were collected from the eastern foothills of the Helan Mountains in April 2023 and used as the experimental materials to conduct a one-dimensional horizontal soil column absorption *** experimental groups with gravel contents of 0%,10%,20%,30%,40%,and 50%were established to determine the saturated hydraulic conductivity(K_(s)),saturated water content(θ_(s)),initial water content(θ_(i)),and retention water content(θ_(r)),and explore the changes in the wetting front depth and cumulative absorption volume during the absorption *** Philip model was used to fit the soil absorption process and determine the soil water absorption *** the length of the characteristic wetting front depth,shape coefficient,empirical parameter,inverse intake suction and soil water suction were derived from the van Genuchten ***,the hydraulic parameters mentioned above were used to fit the soil water characteristic curves,unsaturated hydraulic conductivity(K_(θ))and specific water capacity(C(h)).The results showed that the wetting front depth and cumulative absorption volume of each treatment gradually decreased with increasing gravel *** with control check treatment with gravel content of 0%,soil water absorption rates in the treatments with gravel contents of 10%,20%,30%,40%,and 50%decreased by 11.47%,17.97%,25.24%,29.83%,and 42.45%,*** the gravel content increased,inverse intake suction gradually increased,and shape coefficient,K_(s),θ_(s),andθ_(r)gradually *** the same soil water content,soil water suction and K_(θ)gradually decreased with increasing gravel *** the same soil water s

关键词： stony soil gravel content water absorption characteristics hydraulic parameters one-dimensional horizontal soil column absorption experiment van Genuchten model eastern foothills of Helan Mountains

Optimal search path planning of UUV in battlefeld ambush scene

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Defence Technology（防务技术） 2024年第2期32卷 541-552页

作者： Wei Feng yan ma Heng Li Haixiao Liu Xiangyao Meng Mo Zhou Naval Research Institute Beijing100161China

Aiming at the practical application of Unmanned Underwater Vehicle(UUV)in underwater combat,this paper proposes a battlefield ambush scene with UUV considering ocean ***,by establishing these mathematical models of ocean current environment,target movement,and sonar detection,the probability calculation methods of single UUV searching target and multiple UUV cooperatively searching target are given ***,based on the Hybrid Quantum-behaved Particle Swarm Optimization(HQPSO)algorithm,the path with the highest target search probability is ***,through simulation calculations,the influence of different UUV parameters and target parameters on the target search probability is analyzed,and the minimum number of UUVs that need to be deployed to complete the ambush task is demonstrated,and the optimal search path scheme is *** method proposed in this paper provides a theoretical basis for the practical application of UUV in the future combat.

关键词： Battlefield ambush Optimal search path planning UUV path Planning Probability of cooperative search

Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 468-476页

作者： ZHANG Shouchuan LIU Kai ma yan WANG Luyao SUN Junliang Chinese Academy of Geological Sciences Beijing 100037China School of Water Resources and Environment China University of Geosciences(Beijing)Beijing 100083China

Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic *** study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health *** results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/*** NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited ***,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline ***,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic *** alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population *** results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s *** findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District.

关键词： fluoride concentration nitrate pollution genetic mechanism health risk assessment Tongzhou District

Influence of in situ formed spinel in bonding phase on mechanical properties and air permeability of magnesia-chrome porous purging materials

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1459-1472页

作者： Yi An Hao Liu Zhou-fu Wang yan ma Xi-tang Wang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

magnesia-chrome porous purging plugs are crucial functional components to remove inclusions and stabilize the flow field during iron and steel ***,practical applications of magnesia-chrome porous purging materials are stil hampered by the poor scouring resistance to molten steel and unstable air permeability owing to their low mechanical properties and uncontrollable pore ***,the particle-packing type magnesiachrome porous purging materials reinforced by in situ formed spinel were prepared using fused magnesia-chrome particles and Al powders as major raw *** results show that in situ formed spinel solid solutions in bonding phase led to the decreased median pore size and increased pore surface fractal dimension from the reactions between Al powders and magnesia-chrome particles and along with high-temperature sintering,bonding between magnesia-chrome particles and the resultant mechanical properties of materials were greatly ***,the results of air permeability tests and polynomial ftting indicated that the formation of spinel solid solutions was the main contributing factor for controllable air permeability,and pressure drop of porous purging materials was positively correlated with surface fractal dimension of ***,the as-prepared porous purging materials added with 6 wt.%Al powders obtained the maximum cold crushing strength(54.2 MPa)and hot modulus of rupture(12.9 MPa)with median pore size of 24.06μm and ftting non-Darcian permeability coefficient of 0.97×10^(-6)m.

关键词： magnesia Chrome porous purging material Metallic Al-Spinel Mechanical strength Air permeability

Geochemical and Isotopic Techniques Constraints on the Origin,Evolution,and Residence Time of Low-enthalpy Geothermal Water in Western Wugongshan,SE China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 801-818页

作者： WANG Luyao LIU Kai ma yan ZHANG Yaoyao TONG Jue JIA Wuhui ZHANG Shouchuan SUN Junliang Chinese Academy of Geological Sciences Beijing 100037China School of Water Resources and Environment China University of Geoscience(Beijing)Beijing 100083China The Fourth Geological Brigade of Jiangxi Geological Bureau PingxiangJiangxi 337000China

Geothermal resources are increasingly gaining attention as a competitive,clean energy source to address the energy crisis and mitigate climate *** Wugongshan area,situated in the southeast coast geothermal belt of China,is a typical geothermal anomaly and contains abundant medium-and low-temperature geothermal *** study employed hydrogeochemical and isotopic techniques to explore the cyclic evolution of geothermal water in the western Wugongshan region,encompassing the recharge origin,water-rock interaction mechanisms,and residence *** results show that the geothermal water in the western region of Wugongshan is weakly alkaline,with low enthalpy and mineralization *** hydrochemistry of geothermal waters is dominated by Na-HCO_(3)and Na-SO_(4),while the hydrochemistry types of cold springs are all Na-HCO_(3).The hydrochemistry types of surface waters and rain waters are NaHCO_(3)or Ca-HCO_(3).The δD and δ^(18)O values reveal that the geothermal waters are recharged by atmospheric precipitation at an altitude between 550.0 and 1218.6 *** ratios of maj or solutes and isotopic compositions of^(87)Sr/^(86)Sr underscore the significant role of silicate weathering,dissolution,and cation exchange in controlling geothermal water ***,geothermal waters experienced varying degrees of mixing with cold water during their ***δ^(13)C values suggest that the primary sources of carbon in the geothermal waters were biogenic and ***δ^(34)S value suggests that the sulfates in geothermal water originate from sulfide minerals in the surrounding *** dating using 3H and^(14)C isotopes suggests that geothermal waters have a residence time exceeding 1 kaBP and undergo a long-distance cycling process.

关键词： geothermal water hydrochemistry isotope residence time Wugongshan area

A process insight into production of ethyl levulinate via a stepwise fractionation

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Journal of Bioresources and Bioproducts 2024年第2期9卷 233-242页

作者： yan ma Hongxiao Wang Ziyang Wu Weihong Tan Guodong Feng Jianchun Jiang Institute of Chemical Industry of Forest Products Chinese Academy of ForestryNanjing 210042China Jiangsu Province Key Lab.of Biomass Energy and material Nanjing 210042China National Engineering Lab.for Biomass Chemical Utilization Nanjing 210042China Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry UniversityNanjing 210037China

Ethyl levulinate(EL)is a key biomass-derived compounds due to its socio-economic benefits for the synthesis of commodity ***,we proposed an efficient one-step bamboo conversion to EL in ethanol,and a novel stepwise fractionation to purify EL and lignocellulose degradation products.A proton acid,due to its high catalytic efficiency,yielded 26.65%EL in 120 min at 200℃.The productions of ethyl glucoside and 5-ethoxymethylfurfural were analyzed in terms of by-products *** the best of our knowledge,there is no single report on catalyst for one step synthesis of EL directly from bamboo,as well as a stepwise fractionation to purify *** to similar physiochemical properties in each fraction,the platform molecules could broaden a new paradigm of bamboo biomass utilization for renewable energy and value-added *** addition,glucose,ethyl glucoside,corn starch,and microcrystalline cellulose were also investigated as substrates,so that the reaction intermediates of this one-pot procedure were identified and a possible reaction mechanism was proposed.

关键词： Ethyl levulinate Liquefaction Biomass Ethanol By-products

Efficacy and Safety of Chinese Herbal Medicines Combined with Chemical Drugs for Alzheimer's Disease:A Systematic Review and Meta-Analysis

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 1-13页

作者： Li Xu Wen-Jun Chen Cai-Jun Tian yan Zhang yan ma Tian-Hao Li Hong-Jie Liu Zhe Zhang Department of the First College English College of Foreign LanguageShandong University of Traditional Chinese MedicineJinanChina Department of Oncology Linyi People's HospitalLinyiChina Department of Internal Medicine of Traditional Chinese Medicine The First Clinical CollegeShandong University of Traditional Chinese MedicineJinanChina Department of Chinese materia Medica College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina Department of Medicinal Chemistry College of PharmacyShandong University of Traditional Chinese MedicineJinanChina Community Healthcare Center Shenzhen Traditional Chinese Medicine HospitalShenzhenChina Department of Fundamentals of Traditional Chinese Medicine School of Traditional Chinese MedicineJinan UniversityGuangzhouChina Shandong Co-Innovation Center of Classic TCM Formula College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina

Objective:To evaluate the efficacy and safety of Chinese herbal medicines(CHMs)combined with chemical drugs for the treatment of Alzheimer's disease(AD).materials and Methods:Databases were searched to retrieve randomized controlled trials(RCTs)of CHMs combined with tacrine,galantamine,rivastigmine,donepezil,or memantine,following strict inclusion and exclusion *** research papers published in English,Chinese,and Japanese were *** primary outcome was the mini-mental state examination(MMSE)score and the secondary outcomes were AD assessment scale cognitive subscale(ADAS-Cog)score and safety ***-analysis was carried out using Rev man 5.3 and subgroup analysis was conducted to identify the sources of ***:A total of 15 RCTs with 1386 participants were included in this *** donepezil was used in the retrieved ***-analyses showed that the combination of CHMs with donepezil led to significant improvement in the MMSE score(Z=9.45;P<0.00001;weighted mean difference[WMD]=2.68,95%confidence interval[CI]:2.12-3.24)and a significant decrease in the ADAS-Cog score(Z=5.53;P<0.00001;WMD=-3.79;95%CI:-5.13--2.44).Safety evaluation demonstrated that these combination treatments relieved adverse events such as insomnia(risk ratio[RR]=0.20,95%CI:0.06-0.68;P=0.01)and hive(RR=0.10;95%CI:0.01-0.73;P=0.02).Conclusions:The combination of CHMs with a chemical drug like donepezil led to significant improvements in patient cognition as well as a better safety profile when compared to the application of a chemical drug alone.

关键词： Alzheimer's disease Chinese herbal medicine donepezil memantine meta-analysis randomized controlled trials rivastigmine

Simultaneous determination of five plant hormones in cotton leaves using QuEChERS combined with HPLC‒MS/MS

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Journal of Cotton Research 2024年第2期7卷 163-176页

作者： WANG Wenhao SONG Xianpeng WANG Dan ma Yajie SHAN Yongpan REN Xiangliang HU Hongyan WU Changcai yanG Jun ma yan National Key Laboratory of Cotton Biobreeding and Integrated Utilization Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyangHenan 455000China College of Agriculture Hebei Agricultural UniversityBaodingHebei 071000China Zhengzhou Research Base National Key Laboratory of Cotton Biobreeding and Integrated UtilizationZhengzhou UniversityZhengzhouHenan 450001China Western Agricultural Research Center Chinese Academy of Agricultural SciencesChangjiXinjiang 831100China

Background Plant hormones profoundly influence cotton growth,development,and responses to various ***,there is a pressing need for an efficient assay to quantify these hormones in *** this groundbreaking study,we have established QuEChERS-HPLC‒MS/MS method,for the simultaneous detection of multiple plant hormones in cotton leaves,allowing the analysis and quantification of five key plant *** Sample extraction and purification employed 0.1%acetic acid in methanol and C18 for optimal recovery of plant *** method applied to cotton demonstrated excellent linearity across a concentration range of 0.05–1 mg・L−1,with linear regression coefficients exceeding *** limits of quantification(LOQs)were 20μg・kg−1 for GA3 and 5μg・kg−1 for the other four plant *** rates for the five plant hormones matrix spiked at levels of 5,10,100,and 1000μg・kg−1 were in the range of 79.07%to 98.97%,with intraday relative standard deviations(RSDs)ranging from 2.11%to 8.47%.The method was successfully employed to analyze and quantify the five analytes in cotton leaves treated with plant growth *** The study demonstrates that the method is well-suited for the determination of five plant hormones in *** exhibits excellent selectivity and sensitivity in detecting field samples,thus serving as a robust tool for indepth research into cotton physiology.

关键词： Cotton Plant hormones QuEChERS HPLC‒MS/MS

Establishment of an Iron Deficiency Model by Iron Depletion in Pregnant Rats

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Biomedical and Environmental Sciences 2024年第2期37卷 210-215页

作者： CHEN Xi HAN Chao ZHAO Jin Peng SHEN Shi WANG Li Yuan REN Shou WANG Tong Lei ma yan XU Ze Chao HUO Jun Sheng Key Laboratory of Trace Element Nutrition National Health Commission of the People’s Republic of ChinaNational Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China

Anemia,a global public health problem,has significant adverse consequences on the cognitive development of children and the work capacity of adults;affecting social and economic ***,roughly 43%of children under five years of age,38%of pregnant women,and 29%of nonpregnant women had *** during pregnancy significantly increases the risk of low birth weight and preterm birth.A 10 g/L increase in hemoglobin has been estimated to decrease the risk of maternal and perinatal mortality by 29%and 28%.

关键词： mortality pregnancy anemia