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Climate change indirectly enhances sandstorm prevention services by altering ecosystem patterns on the Qinghai-Tibet Plateau

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Journal of Mountain Science 2021年第7期18卷 1711-1724页

作者： MENG nan YANG Yan-zheng ZHENG Hua LI Ruo-nan State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China University of Chinese Academy of Sciences Beijing100049China View author publications

Climate change influences both ecosystems and ecosystem *** impacts of climate change on ecosystems and ecosystem services have been separately ***,it is less well known how ecosystem changes driven by climate change will influence ecosystem services,especially in climate-sensitive ***,we analyzed future climate trends between 2040 and 2100 under four Shared Socioeconomic Pathway(SSP) scenarios(SSP1-2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5) from the Coupled Model Intercomparison Project 6(CMIP6).We quantified their impacts on ecosystems patterns and on the ecosystem service of sandstorm prevention on the Qinghai-Tibet Plateau(QTP),one of the most climate-sensitive regions in the world,using Random Forest model(RF) and Revised Wind Erosion Equation(RWEQ).Strong warming(0.04℃/yr) and wetting(0.65 mm/yr) trends were projected from 2015 to *** these trends,there will be increased interspersion in the pattern of grassland and sparse vegetation with meadow and swamp vegetation,although their overall area will remain similar,while the areas of shrub and needleleaved forest classes will increase and move toward higher *** by the changes in ecosystem patterns caused by climate change indirectly,grassland will play an irreplaceable role in providing sandstorm prevention services,and sandstorm prevention services will increase gradually from 2040 to 2100(1.059-1.070 billion tons) on the ***,some areas show a risk of deterioration in the future and these should be the focus of ecological *** research helps to understand the cascading relationship among climate change,ecosystem patterns and ecosystem services,which provides important spatio-temporal information for future ecosystem service management.

关键词： Qinghai-Tibet Plateau Climate change Sandstorm prevention services Coupled Model Intercomparison Project 6 Random Forest model Revised Wind Erosion Equation

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Common variants in PERK, JNK, BIP and XBP1 genes are associated with the risk of prediabetes or diabetes-related phenotypes in a Chinese population

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Chinese Medical Journal 2014年第13期127卷 2438-2444页

作者： Feng nan Ma Xiaowei Wei Xiaowei Zhang Junqing Dong Aimei Jin mengmeng Zhang Hong Guo Xiaohui Department of Endocrinology Peking University First HospitalBeijing 100034 China Department of Endocrinology General Hospital of Chinese People'sLiberation Army Beijing 100853 China

Background Prediabetes is an early stage of β-cell dysfunction presenting as insulin *** suggest that endoplasmic reticulum （ER） stress is involved in the pathogenesis of type 2 diabetes mellitus and *** a Chinese population with prediabetes,we investigated single nucleotide polymorphisms （SNPs） in the genes of PERK,JNK,XBP1,BIP and CHOP which encode molecular proteins involved in ER stress *** Nine SNPs at the PERK,JNK,XBP1,BIP and CHOP loci were genotyped by mass spectrometry in 1 448 unrelated *** using a 75 g oral glucose tolerance test （OGTT）,828 subjects were diagnosed as prediabetes and 620 subjects aged 55 years and over as normal controls based on WHO diagnostic criteria （1999） for diabetes *** The allele C of SNP rs867529 at PERK locus was a risk factor for prediabetes,with the carriers of C allele genotype at a higher risk of prediabetes compared to non-carriers （OR=1.279,95％ CI：1.013-1.614,P=0.039,after adjustment for age,sex and body mass index （BMI）.The SNPs rs6750998 at PERK locus was associated with homeostasis model assessments of insulin resistance （HOMA-IR）（P=0.019）,and rs17037621 with BMI （P=0.044）.The allele G of SNP rs10986663 in BIP gene was associated with a decreased risk of prediabetes （OR=0.699,95％ CI：0.539-0.907,P=0.007）.The SNP rs2076431 in JNK gene was associated with fasting plasma glucose levels （P=0.006） and waist-hip ratios （P=0.019）.The SNP rs2239815 in XBP1 gene was associated with 2-hour plasma glucose levels after 75 g oral glucose load （P=0.048） in the observed *** Common variants at PERK and BIP loci contributed to the risk of prediabetes,and the genetic variations in JNK and XBP1 genes are associated with diabetes-related clinical parameters in this Chinese population.

关键词： unfolded protein response pathway genes endoplasmic reticulum stress single nucleotide polymorphisms prediabetes

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Personal Review:Research on ethanol synthesis from syngas

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 714-719页

作者： Jie HE Wen-nan ZHANG Qingdao Institute of Biomass Energy and Bioprocess Technology Chinese Academy of Sciences Qingdao 266071 China

It is a very fine substitutable energy technology to synthesize ethanol from biomass-derived syngas. This paper summarized the development of preparing ethanol from syngas, and especially elaborated on the research status of catalysts for the process. Based on the relative researches on the reaction mechanism, structure and performance of the catalysts, the optimum design of catalysts with high activity was presented in this review, which set the theoretical and application foundation for the industrial production of ethanol from syngas.

关键词： Syngas Catalyst Ethanol Biomass Promoter

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Bending results of graphene origami reinforced doubly curved shell

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Defence Technology（防务技术） 2024年第5期35卷 198-210页

作者： nan Yang Yunhe Zou Mohammad Arefi School of Architecture and Civil Engineering Qiqihar UniversityQiqihar 161006HeilongjiangChina School of Mechanical Engineering Inner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina Inner Mongolia Key Laboratory of Special Service Intelligent Robotics Hohhot 010051Inner MongoliaChina Faculty of Mechanical Engineering Department of Solid MechanicsUniversity of KashanKashan87317-51167Iran

The present work investigates higher order stress,strain and deformation analyses of a shear deformable doubly curved shell manufactures by a Copper(Cu)core reinforced with graphene origami auxetic metamaterial subjected to mechanical and thermal *** effective material properties of the graphene origami auxetic reinforced Cu matrix are developed using micromechanical models cooperate both material properties of graphene and Cu in terms of temperature,volume fraction and folding *** principle of virtual work is used to derive governing equations with accounting thermal *** numerical results are analytically obtained using Navier's technique to investigate impact of significant parameters such as thermal loading,graphene amount,folding degree and directional coordinate on the stress,strain and deformation responses of the *** graphene origami materials may be used in aerospace vehicles and structures and defence technology because of their low weight and high stiffness.A verification study is presented for approving the formulation,solution methodology and numerical results.

关键词： Graphene origami Copper matrix Doubly curved Shear deformable Auxetic metamaterial

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Support vector machine based machine learning method for GS 8QAM constellation classification in seamless integrated fiber and visible light communication system

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Science China(Information Sciences) 2020年第10期63卷 182-193页

作者： Wenqing NIU Yinaer HA nan CHI Key Laboratory for Information Science of Electromagnetic Waves (MoE) Fudan University

Visible light communication(VLC) network over optical fiber has become a potential candidate in ultra-high speed indoor wireless communication. To mitigate signal distortion accumulated in optical fiber and VLC channel, we present to utilize support vector machine(SVM) for constellation classification in two kinds of geometrically-shaped 8 QAM(quadrature amplitude modulation) seamless integrated fiber and VLC system. We introduce 4 sub-bands to simulate multi-user. Experimental results show that system performance can be significantly improved, and transmission at-2.5 dB m input optical power under 7%forward error correction(FEC) threshold can be realized employing Circular(7, 1) geometrically-shaped8 QAM and SVM. At overall capacity of 960 Mbps, Q-factor increases by up to 11.5 dB.

关键词： visible light communication VLC support vector machine SVM geometrically shaping GS VLC network constellation classification

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An effective method to determine bedding system insulation based on measured data

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Building Simulation 2023年第1期16卷 121-132页

作者： nan Zhang Bin Cao Yingxin Zhu Department of Building Science School of ArchitectureTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Indoor Air Quality Evaluation and Control(Tsinghua University) Beijing 100084China Key Laboratory of Eco Planning&Green Building Ministry of Education(Tsinghua University)Beijing 100084China

The thermal environment is an essential factor that affects sleep *** many circumstances,the bed microenvironment is more important than the ambient environment because of the large covered area of the human body and the close contact between the bedding system and the human *** main objective of this research is to establish an effective method to determine bedding system insulation.A thermal manikin was used in the measurement of bedding system *** different types of quilts,which were filled with cotton,polyester and duvet respectively,were chosen to be *** total ten different quilts with different materials and weights were involved in the *** regular arrangements of covers were chosen with coverage rates of 94.1%,85.9%,70.6%,and 54.4%to test.A total of 64 bedding systems were tested to build an effective method to determine the bedding system *** the basis of test data,the change of bedding system insulation with coverage was found to be *** fitting was applied to establish an insulation evaluation method for bedding system *** addition,the effects of quilt cover and sleepwear on bedding system insulation were discussed and thermal insulation increment caused by quilt cover and sleepwear were *** relationships between neutral indoor temperature and weight per unit area of the quilt for different coverage rates have been quantified based on existing subject *** research provides an effective method to determine bedding system insulation,which can be widely used in thermal comfort research and HVAC system design.

关键词： sleep environment bedding system thermal insulation thermal comfort

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Regulation of sporopollenin synthesis for pollen wall formation in plant

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Science China(Life Sciences) 2016年第12期59卷 1335-1337页

作者： Zhong-nan Yang College of life and environmental sciences Shanghai Normal University

Pollen wall is the most complicated cell wall in plant. It is composed of outer exine and inner intine with the exine fiar- ther divided into sexine and nexine. The composition of in- tine layer is generally considered to be same as a plant cell wall which is mainly composed of cellulose. Nexine layer can only be observed under transmission electron microscope. Recent investigation suggested that the major composition of nexine is arabinogalactan proteins （Jia et al., 2015）.

关键词： pollen cellulose outer

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Particles in composite polymer electrolyte for solid-state lithium batteries:A review

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Particuology 2022年第1期20卷 14-36页

作者： nan Meng Xiaogang Zhu Fang Lian School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Solid-state lithium batteries(SSLBs)have been identified as one kind of the most promising energy conversion and storage devices because of their safety,high energy density,and long cycling *** development of solid-state electrolyte is vital to commercialize *** polymer electrolyte(CPE),derived by compositing inorganic particles into solid polymer electrolyte has become the most practical species for SSLBs because it inherits the advantages of polymer electrolyte and simultaneously achieves enhanced ionic conductivity and mechanical *** characteristics of inorganic particles and their interaction with polymers strongly impact the performance of CPE,improving its ionic conductivity,mechanical properties,thermal and electrochemical stability,as well as interface compatibility with both *** this review,the effects of particle characteristics including its species,size,proportion,morphology on the ionic conductivity and mechanical properties of CPE are ***,some novel composite strategies are also introduced including surface modification,hybridization,and alignment of particles in polymer matrices,as well as some new preparation methods of *** interactions between particles and other components in CPE including polymer matrices or lithium salt are particularly focused herein to reveal the lithium conductive ***,a perspective on the direction of future CPE development for SSLBs is presented.

关键词： Particles Composite polymer electrolyte Ionic conductivity Interaction Interface Solid-state

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Optical wavelet-fractional squeezing combinatorial transform

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Chinese Physics B 2022年第2期31卷 209-216页

作者： Cui-Hong Lv Ying Cai nan Jin nan Huang School of Physics and Electronic Engineering Jiangsu UniversityZhenjiang 212013China

By virtue of the method of integration within ordered product(IWOP)of operators we find the normally ordered form of the optical wavelet-fractional squeezing combinatorial transform(WFrST)*** way we successfully combine them to realize the integration transform kernel of WFr ST is making full use of the completeness relation of Dirac’s ket–bra *** WFr ST can play role in analyzing and recognizing quantum states,for instance,we apply this new transform to identify the vacuum state,the single-particle state,and their superposition state.

关键词： wavelet transform fractional squeezing transform combinatorial transform IWOP technique

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Electrical Power Generation Using Dynamic Piezoelectric Shear Deformation Under Friction

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Acta Mechanica Solida Sinica 2021年第6期34卷 977-988页

作者： Peng Wang Yu Xiao nan Wu Department of Mechanical Engineering Northeastern UniversityShenyang 110819China Department of Mechanical Engineering University of ManitobaWinnipeg R3T 2N2Canada

A new electrical power generation device based on high-frequency dynamic piezoelectric shear deformation under friction is *** the operation of a moving plate compressed and sliding on the top of a piezoelectric patch with constant velocity,dynamic shear deformation of the elastic piezoelectric patch is excited by periodic friction force and status(sliding and stick)*** dynamic piezoelectric shear strain can then generate continuous electrical power for energy absorbing and harvesting *** design of the piezoelectric couple device is first provided,and its mechanism,dynamic response and electric power generation under friction are described by a detailed iteration *** comparing with previous experimental results,the accuracy of the proposed model is *** numerical studies,the influences of the equivalent mass of the system,the velocity of the sliding object,the static friction coefficient and its lower limit,as well as the friction force delay rate on the power generation are obtained and *** numerical results show that with the proposed design,up to 50-Watt maximum electrical power could be generated by a piezoelectric patch with a dimension of 20×2×6 cm under continuous friction with the moving plate at the velocity of 15 m/*** possible bi-linear elastic stiffness variation of the system is also introduced,and the threshold of bi-linear elastic deformation,where the system stiffness changes,can be optimized for obtaining the highest power generation.

关键词： Electrical power generation Friction Piezoelectric shear deformation Sliding and stick Bi-linear

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