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Variability in pattern and hydrogen isotope composition(δ^(2)H)of long-chain n-alkanes of surface soils and its relations to climate and vegetation characteristics:A meta-analysis

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Pedosphere 2022年第3期32卷 369-380页

作者： guo CHEN Xiaozhen LI Xiaolu TANG Wenyi qin Haitao liu Michael ZECH Karl AUERSWALD College of Ecology and Environment Chengdu University of TechnologyChengdu 610059(China) College of Earth Science Chengdu University of TechnologyChengdu 610059(China) Resources and Environment College Henan Agricultural UniversityZhengzhou 450002(China) Heisenberg Chair of Physical Geography with Focus on Paleoenvironmental Research Institute of GeographyTechnische Universität DresdenDresden 01062(Germany) Technische Universität München Alte Akademie 12Freising-Weihenstephan 85354(Germany)

The average chain length(ACL),carbon preference index(CPI),and hydrogen isotope composition(δ^(2)H)of long-chain n-alkanes in sediments have been used to retrieve information about the *** their importance as in-between media from leaves to sediments,n-alkanes of surface soils have not been systematically analyzed at large *** an investigation of the spatial variation of n-alkane properties in soil and their dependence on climatic and botanic(e.g.,vegetation type)factors could provide a rationale for a better estimation of the past *** synthesized the patterns andδ^(2)H of long-chain n-alkanes in soil(δ^(2)H_(n-alkanes))with regard to vegetation types(cropland,grassland,shrubland,and woodland)and environmental factors using data from peer-reviewed *** results showed that the ACL and CPI of soil C_(27)–C_(33) n-alkanes were not suitable indicators for differentiating vegetation types at large scale;instead,ACL significantly correlated with water conditions such as mean annual precipitation(MAP)and Palmer drought severity index(PDSI),and CPI significantly correlated with temperature without significant influence of vegetation *** variation(i.e.,standard deviation)of fractionation between theδ^(2)H values in annual precipitation and in soil n-alkanes(ε_(rain-soil))was smaller than that reported in leaves;therefore,soils were better suited to quantifying the general growing conditions of plants at a certain *** fractionationε_(rain-soil)correlated with climatic conditions as described by the PDSI and relative humidity(RH).This correlation agreed with the change in leaf water enrichment with changing RH taken from the literature and was independent of the vegetation type at large *** meta-analysis may provide useful information for the variations of the patterns andδ^(2)H_(n-alkanes) values in surface soils.

关键词： average chain length(ACL) altitude carbon preference index(CPI) leaf water moisture precipitation topsoil vegetation type

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Interval standard neural network models for nonlinear systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 530-538页

作者： liu Mei-qin School of Electrical Engineering Zhejiang University Hangzhou 310027 China

A neural-network-based robust control design is suggested for control of a class of nonlinear systems. The design ap- proach employs a neural network, whose activation functions satisfy the sector conditions, to approximate the nonlinear system. To improve the approximation performance and to account for the parameter perturbations during operation, a novel neural network model termed standard neural network model (SNNM) is proposed. If the uncertainty is bounded, the SNNM is called an interval SNNM (ISNNM). A state-feedback control law is designed for the nonlinear system modelled by an ISNNM such that the closed-loop system is globally, robustly, and asymptotically stable. The control design equations are shown to be a set of linear matrix inequalities (LMIs) that can be easily solved by available convex optimization algorithms. An example is given to illustrate the control design procedure, and the performance of the proposed approach is compared with that of a related method reported in literature.

关键词： Interval standard neural network model (ISNNM) Linear matrix inequality (LMI) Nonlinear system Asymptotic stability Robust control

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Synthesis of multi-hydroxyl and sulfonyl dual-functionalized room temperature ionic liquids

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Chinese Chemical Letters 2007年第6期18卷 633-635页

作者： guo Yang Zhu Rong Wang guo Hua liu Li Qun Xu Bei Zhang Xia qin Wu College of Life and Environment Science Shanghai Normal University Shanghai 200234 China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha 410082 China

Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ionic liquids have been synthesized. The hydroxyl groups of the synthesized substances were confirmed by the 1H NMR measurement. These zwitterionic salts and ionic liquids may be used for synthesizing other functionalized ionic liquids or ionic liquid-polymer (polyelectrolyte).

关键词： Dual-functionalized Zwitterionic salt Room temperature ionic liquids Polymerization

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Wear Property of Cast Steel Wheel Material in Rail Truck

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Journal of Iron and Steel Research International 2009年第3期16卷 73-77页

作者： MI guo-fa liu Yan-lei ZHANG Bin FU Xiu-qin ZHANG Hong SONG guo-xiang School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454003 Henan China Metals and Chemistry Institute China Academy of Railway Sciences Beijing 100081 China Datong ABC Casting Co Ltd Datong 037038 Shanxi China

Wear property of material plays a key role in the service time of workpiece. A major objective in the development of new wheel materials is to improve the wear performance. The wear property of B and B＋ grade cast steel materials was reported. The results showed that B＋ grade cast steel material exhibited better wear property than the B grade material. Carbon content related to the hardness match was the principal factor affecting the wear properties.

关键词： wear property wheel hardness carbon content

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Magnetic Array Assisted Triboelectric Nanogenerator Sensor for Real‑Time Gesture Interaction

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Nano-Micro Letters 2021年第3期13卷 168-176页

作者： Ken qin Chen Chen Xianjie Pu Qian Tang Wencong He Yike liu Qixuan Zeng Guanlin liu Hengyu guo Chenguo Hu Department of Applied Physics State Key Laboratory of Power Transmission Equipment&System Security and New TechnologyChongqing Key Laboratory of Soft Condensed Matter Physics and Smart MaterialsChongqing UniversityChongqing 400044People’s Republic of China Center On Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNanningGuangxi 530004People’s Republic of China

In human-machine interaction,robotic hands are useful in many *** operate robotic hands via gestures instead of handles will greatly improve the convenience and intuition of human-machine ***,we present a magnetic array assisted sliding triboelectric sensor for achieving a real-time gesture interaction between a human hand and robotic *** a finger’s traction movement of flexion or extension,the sensor can induce positive/negative pulse *** counting the pulses in unit time,the degree,speed,and direction of finger motion can be judged in *** magnetic array plays an important role in generating the quantifiable *** designed two parts of magnetic array can transform sliding motion into contact-separation and constrain the sliding pathway,respectively,thus improve the durability,low speed signal amplitude,and stability of the *** direct quantization approach and optimization of wearable gesture sensor provide a new strategy for achieving a natural,intuitive,and real-time human-robotic interaction.

关键词： Sliding triboelectric sensor Magnetic array Gesture Real-time Human-machine interaction

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Highly efficient fermentation of glycerol and 1,3-propanediol using a novel starch as feedstock

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Food Bioscience 2022年第2期46卷 200-208页

作者： You Yang Ying Chen Yanling Jin Jing liu Xiang qin Wenjun liu Ling guo Department of Pediatrics Children Hematological Oncology and Birth Defects LaboratoryThe Affiliated Hospital of Southwest Medical UniversitySichuan Clinical Research Center for Birth DefectsLuzhouSichuan646000China CAS Key Laboratory of Environmental and Applied Microbiology Environmental Microbiology Key Laboratory of Sichuan ProvinceChengdu Institute of BiologyChinese Academy of SciencesChengduSichuan610041China National Engineering Research Center for Non-Food Biorefinery Guangxi Academy of SciencesNanningGuangxi530007China

As a potential cost-effective feedstock for highly efficient fermentation of glycerol and its downstream product 1,3-propanediol(1,3-PD),duckweed starch was characterized and used for glycerol fermentation,for the first time,in this *** involved in glycerol biosynthesis(gpd1 and gpp2)were overexpressed in Escherichia coli,and genes involved in glycerol catabolism(glpK and gldA)were disrupted,which led to significantly decreased residual sugar levels and dramatically increased glycerol *** maximum glycerol concentration in fed-batch fermentation reached 102.72 g L^(-1) at 28 h,and the glycerol productivity was 3.67 g L^(-1) h^(-1),which,to our knowledge,is the highest productivity thus far ***,glycerol broth was fermented into 1,3-PD by Klebsiella *** concentration,conversion rate and productivity of 1,3-PD reached 35.54 g L^(-1),40.28%and 0.89 g L^(-1) h^(-1),respectively,without *** summary,the duckweed starch-to-glycerol-to-1,3-PD process is feasible and shows potential for improving glycerol industry competitiveness.

关键词： Duckweed starch Glycerol 1,3-Propanediol Fed-batch fermentation Biosynthesis

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Antihyperglycemic,antihyperlipidemic and antioxidant effects of standard ethanol extract of Bombax ceiba leaves in high-fat-diet-and streptozotocin-induced Type 2 diabetic rats

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Chinese Journal of Natural Medicines 2017年第3期15卷 168-177页

作者： XU Guang-Kai qin Xiao-Ying WANG guo-Kai XIE guo-Yong LI Xu-Sen SUN Chen-Yu liu Bao-Lin qin Min-Jian State Key Laboratory of Natural Medicines Department of Resources Science of Traditional Chinese MedicinesChina Pharmaceutical UniversityNanjing 210009China Anhui Key Laboratory of Modernized Chinese Materia Medica Anhui University of Traditional Chinese MedicineHefei 230012China Department of Pharmacology of Chinese Materia Medica China Pharmaceutical UniversityNanjing 210009China

The present study aimed at exploring the therapeutic potential of standard extract of Bombax ceiba ***(BCE) in type 2 diabetic mellitus(T2DM).Oral administration of BCE at doses of 70,140,and 280 mg·kg^(-1),to the normal rats and the high-fat-diet-and streptozotocin-induced T2 DM rats were carried *** of BCE on blood glucose,body weight,and a range of serum biochemical parameters were tested,and histopathological observation of pancreatic tissues was also ***-ESI-Q/TOF-MS/MS analysis indicated that the chemical composition of BCE mainly contained mangiferin,isoorientin,vitexin,isomangiferin,isovitexin,quercetin hexoside,2'-trans-O-cumaroyl mangiferin,and *** caused a significant decrease in the concentrations of fasting blood glucose,glycosylated hemoglobin,total cholesterol,triglyceride,low density lipoprotein-cholesterol,serum insulin,and malondialdehyde,and increases in oral glucose tolerance,high density lipoprotein-cholesterol,and superoxide dismutase in the T2 DM model ***,considerable pancreatic β-cells protection effect and stimulation of insulin secretion from the remaining pancreatic β-cells could be observed after BCE *** results indicated that BCE exhibited an excellent hypoglycemic activity,and alleviated dyslipidemia which is associated with T2 *** activity and protecting pancreatic β-cells are the possible mechanisms involved in anti-diabetic activity of BCE.

关键词： Bombax ceiba Type 2 diabetic mellitus Antihyperglycemic Antihyperlipidemic Antioxidant

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内蒙古农牧交错区典型黑土坡耕地土壤侵蚀空间分布特征

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水土保持研究 2025年第1期32卷 13-20页

作者：邹惠杰刘刚舒成博孙波刘亚张琼郭珍中国科学院教育部水土保持与生态环境研究中心黄土高原土壤侵蚀与旱地农业国家重点实验室中国科学院水利部水土保持研究所中国科学院大学西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室四川华标测检测技术有限公司

[目的]定量了解内蒙古典型黑土区土壤侵蚀速率，探究该区域土壤侵蚀空间分布特征，阐明土壤侵蚀坡面和区域空间分布规律，以期为区域水土流失治理提供参考。[方法]采集内蒙古农牧交错区（海拉尔区、额尔古纳市和牙克石市）典型黑土坡耕... 详细信息

[目的]定量了解内蒙古典型黑土区土壤侵蚀速率，探究该区域土壤侵蚀空间分布特征，阐明土壤侵蚀坡面和区域空间分布规律，以期为区域水土流失治理提供参考。[方法]采集内蒙古农牧交错区（海拉尔区、额尔古纳市和牙克石市）典型黑土坡耕地的土壤样品，利用137Cs示踪技术计算各采样点土壤侵蚀速率，结合小波分析的方法研究土壤侵蚀在坡面的分布特征。[结果]（1） 3个坡面所有采样点137Cs含量均小于背景值（1 984.24 Bq/m2）,表现为所有坡面土壤流失。（2） 3个地区的采样坡面平均侵蚀速率表现为：海拉尔[6 533.37 t/（km2·a）]>额尔古纳[4 174.35 t/（km2·a）]>牙克石[2 765.87 t/（km2·a）]。相同坡面的3个纵向断面的平均侵蚀速率相近，同一断面侵蚀速率的变异程度较高。（3）土壤侵蚀速率沿坡长呈强弱交替的周期性变化，但周期长度并不固定。大部分纵向断面存在周期长度为80～160 m和160～200 m的大小两个周期。部分纵向断面只存在一个周期长度为100～120 m的周期。[结论]该地区土壤侵蚀在坡面尺度表现为全坡面侵蚀且在纵向呈现周期性特征，在区域尺度呈现从东到西逐渐增加趋势。

关键词：土壤侵蚀典型黑土农牧交错带小波分析

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Protective effects of Jiayan Kangtai granules on autoimmune thyroiditis in a rat model by modulating Th17/Treg cell balance

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Journal of Traditional Chinese Medicine 2018年第3期38卷 380-390页

作者： Hou Yi Wang Tieshan guo Xiangyu Sun Wen guo Xuan Wu Lili qin Lingling Zhang Chengfei liu Tonghua Key Laboratory of Health Cultivation of the Ministry of Education Beijing University of Chinese Medicine Beijing 100029 China Dongfang Hospital of Beijing University of Chinese Medicine Beijing 100078 China Beijing Research Institute of Chinese Medicine & Beijing University of Chinese Medicine Beijing100029 China Department of Endocrinology Dongfang Hospital of Beijing University of Chinese Medicine Beijing100078 China Beijing Key Laboratory of Health Cultivation Beijing University of Chinese Medicine Beijing 100029China Science and Technology Department Beijing University of Chinese Medicine Beijing 100029 China

OBJECTIVE: To investigate the protective effects of Jiayan Kangtai(JYKT) granules, consisting of 9 Chinese herbs, in a rat model of autoimmune thyroiditis(AIT), and the possible underlying ***: Female Lewis rats(6-8 weeks) were randomly apportioned to 5 groups of 10, including a normal control. AIT was induced in the untreated AIT-model group, and rats treated subsequently with daily low, medium, or high dose JYKT granules. After 12 weeks, plasma levels of thyroid autoantibodies and morphological changes in the thyroid were detected by enzyme-linked immunosorbent assay and histological examination, respectively. The presence of interleukin(IL)-6,IL23 p19, and IL-2 in thyroid tissue was assessed by immunohistochemical staining. The percentages of T helper(Th)17 cells and regulatory T cells(Tregs) in the peripheral blood were analyzed by flow cytometry. Relevant levels of cytokines and proteins were examined via bead-based multiplex flow cytometry and ELISA, respectively. Expressions of genes and proteins regulated by Th17 cells and Tregs were shown by real-time PCR and Western ***: Compared to the control, AIT-model rats had higher plasma concentrations of thyroid autoantibodies. The high-dose JYKT rats showed significantly lower levels of thyroid autoantibodies compared with the AIT model group. Rats in the AIT-JYKT groups also had fewer thyroid lesions and less lymphocytic infiltration, a lower percentage of Th17 cells, and a higher percentage of Tregs, compared with the AIT-model. Rats given high-dose JYKT had a significantly lower Th17/Treg ratio compared with the AIT model. Differences in plasma cytokine concentrations and relevant gene and protein expressions in the spleens of JYKT-treated rats and the AIT group suggested an association between JYKT treatment and lower Th17 cell percentage and higher Treg ***: JYKT treatment appeared to be protective against AIT in rats, possibly via the regulation of the Th17 cell/Treg im

关键词： thyroiditis autoimmune Th17 cells T-Lymphocytes regulatory Herbal medicine Jiay-an Kangtai granules

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In situ synthesis of Co_(3)O_(4)nanoparticles confined in 3D nitrogendoped porous carbon as an efficient bifunctional oxygen electrocatalyst

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Rare Metals 2020年第12期39卷 1383-1394页

作者： Zhi-Yuan Wang Shun-Da Jiang Chan-qin Duan Dan Wang Shao-Hua Luo Yan-guo liu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material-Hebei Province Qinhuangdao 066004China

The rational exploitation of non-precious metal catalyst with high activity,strong durability and low cost for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of vital importance for metalair ***,a composite of Co_(3)O_(4)nanoparticles confined in three-dimensional(3 D)N-doped porous carbon(Co-NpCs)was prepared by a simple freeze-drying and in situ pyrolysis *** effect of different dosages of Co(NO_(3))_(2)on the catalytic performance was *** Co-NpC-12%exhibits the best catalytic performance(E_(1/2)=0.78 V,better stability than 20%Pt/C)in ORR and in OER among all the as-synthesized ***,it also exhibits the best bifunctional activity(ΔE=0.849 V).The excellent properties of Co-NpCs are mainly due to the synergy between Co_(3)O_(4)and ***,a high Co_(3)O_(4)loading amount can boost the defect level of the N-doped hierarchical porous carbon and expose more active ***,the unique in situ pyrolysis guarantees a largearea contact between Co_(3)O_(4)and carbon as well as a strong C-O-Co bonding,which promotes charge transfer,avoids the peeling of Co_(3)O_(4)nanoparticles and effectively improves the stability of the *** work is expected to offer a feasible strategy to produce metal oxide/carbon nanocomposite and push forward the development of bifunctional electrocatalyst with high activity and stability.

关键词： Bifunctional electrocatalyst Co_(3)O_(4) Nitrogendoped porous carbon In situ synthesis

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