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Coarse fragment content influences estimates of soil C and N stocks of alpine grassland on the northeastern edge of Qinghai-Tibetan Plateau,China

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Research in Cold and Arid Regions 2022年第2期14卷 100-108页

作者： Yu Qin ShuHua Yi jianjun chen State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesNo.320 West Donggang RoadLanzhouGansu 730000China Institute of Fragile Ecosystem and Environment Nantong UniversityNo.999 Tongjing RoadNantongJiangsu 226007China Guangxi Key Laboratory of Spatial Information and Geomatics No.12 Jiangan RoadGuilinGuangxi 541004China

Soil organic carbon(SOC)and total nitrogen(TN)stocks are usually calculated with samples collected using core *** the calculation considers the effects of gravel in soil samples,other coarse fragments such as stones or boulders in soil may not be collected due to the restricted diameter of core *** would cause an incorrect estimation of soil bulk density and ultimately SOC and TN *** this study,we compared the relative volume of coarse fragment and bulk density of fine earth determined by large size soil sampler with three core *** also investigated the uncertainties in estimation of SOC and TN stocks caused by this soil sampler procedure in three typical alpine grasslands on the northeast edge of the Qinghai-Tibetan Plateau(QTP),*** show that(1)the relative volume and size of coarse fragment collected by large size sampler were significantly(p<0.05)higher and larger than those of core samplers,while bulk density of fine earth,SOC and TN stocks show opposite patterns in all grassland types;(2)SOC and TN stocks determined by core samplers were 17%-45%and 18%-46%higher than larger size sampler for three typical alpine grasslands;and(3)bulk density of fine earth,SOC and TN stocks exponentially decreased with the increasing of coarse fragment *** concluded that core sampler methods significantly underestimated the volume occupied by coarse fragment but overestimated SOC and TN ***,corrections should be made to the results from core samplers using large size samplers on regions with gravel and stone-rich soils in future studies.

关键词： coarse fragment sampler size soil C alpine grassland the Qinghai-Tibetan Plateau

Nanoscale all-optical devices based on surface plasmon polaritons

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Chinese Science Bulletin 2014年第22期59卷 2661-2665页

作者： jianjun chen chengwei Sun Xiaoyong Hu State Key Laboratory for Mesoscopic Physics & Department of Physics Peking University Collaborative Innovation Center of Quantum Matter

Surface plasmon polariton,a kind of surface electromagnetic wave propagating along the interface between metals and dielectrics,provides an excellent platform for the realization of integrated photonic devices due to its unique properties of confining light into subwavelength *** recent research progresses of nanoscale integrated photonic devices based on surface plasmon polaritons,including all-optical switches,all-optical logic discriminator,and all-optical routers,are introduced in detail.

关键词：表面等离子体激元全光器件纳米光子器件全光路由器波的传播全光开关全光逻辑

Oxides Catalysts of Rare Earth and Transient Metal for Catalytic Oxidation of Benzene

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Journal of Rare Earths 2004年第z1期22卷 191-193页

作者： Liang Kun Li Rong chen jianjun Ma Jiantai College of Chemistry and Chemic Engineering Lanzhou University Lanzhou 730000 China College of Chemistry and Chemic Engineering Lanzhou University Lanzhou 730000 China College of Chemistry and Chemic Engineering Lanzhou University Lanzhou 730000 China College of Chemistry and Chemic Engineering Lanzhou University Lanzhou 730000 China

The catalysts of CeO2 and the mixture of CeO2 and CuO were prepared, and the activities of these catalysts for completely oxidizing benzene were *** results show that the optimal proportion of CeO2/CuO is 6: *** highest temperature at which benzene was completely oxidized on these catalysts at different airspeed was *** these catalysts with the noble metal used, our catalysts had superiority in the resources and the industrial cost besides good activities.

关键词： oxides catalysts of rare earth benzene complete oxidation rare earths

Forecast of Piezoelectric Properties of Crystalline Materials from First Principle Calculation

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Journal of Rare Earths 2006年第z1期24卷 217-221页

作者： Zheng Yanqing chen jianjun Zhang Tao Xin Jun Shi Erwei Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China

Piezo crystals including quartz, quartz-like crystals, known and novel crystals of langasite-type structure were treated with density-functional perturb theory (DFPT) using plane-wave pseudopotentials method, within the local density approximation (LDA) to the exchange-correlation functional. Compared with experimental results, the ab initio calculation results have quantitative or semi-quantitative accuracy. It is shown that first principle calculation opens a door to the search and design of new piezoelectric material. Further application of first principle calculation to forecast the whole piezoelectric properties was also discussed.

关键词： first principle calculation DFPT piezoelectricity crystalline materials

Research on single event transient pulse quenching effect in 90 nm CMOS technology

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Science China(Technological Sciences) 2011年第11期54卷 3064-3069页

作者： QIN JunRui chen ShuMing LIU BiWei chen jianjun LIANG Bin LIU Zheng School of Computer Science National University of Defense Technology Changsha 410073 China

Since single event transient pulse quenching can reduce the SET(single event transient) pulsewidths effectively,the charge collected by passive device should be maximized in order to minimize the propagated *** the perspective of the layout and circuit design,the SET pulsewidths can be greatly inhibited by minimizing the layout spacing and signal propagation delay,which sheds new light on the radiation-hardened ICs(integrated circuits) *** show that the SET pulsewidths of propagation are not in direct proportion to the LET(linear energy transfer) of incident particles,thus the defining of the LET threshold should be noted when SET/SEU(single event upset) occurs for the radiation-hardened *** capability of anti-radiation meets the demand when LET is high but some soft errors may occur when LET is ***,radiation experiments should be focused on evaluating the LET that demonstrates the worst response to the circuit.

关键词： SET propagation radiation hardening by design charge collection charge share quenching

陈酿期不同调配比例对赤霞珠-美乐葡萄酒化学成分和感官品质的影响

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核农学报 2024年第4期38卷 703-714页

作者：强文乐余飞赵晓兰李恺安陈建军马腾臻甘肃农业大学食品科学与工程学院/甘肃省葡萄与葡萄酒工程学重点实验室/甘肃省葡萄酒产业技术研发中心甘肃兰州730070 甘肃张掖国风葡萄酒业有限责任公司甘肃张掖734000

为探究不同品种混酿处理对所得葡萄酒色泽参数和挥发性香气成分的影响,本研究以赤霞珠葡萄酒为基酒,在橡木桶陈酿期间采用不同比例(10%、20%、30%、40%)美乐葡萄酒进行二元混酿,陈酿12个月后分析混酿葡萄酒的理化指标、色泽参数、酚类... 详细信息

为探究不同品种混酿处理对所得葡萄酒色泽参数和挥发性香气成分的影响,本研究以赤霞珠葡萄酒为基酒,在橡木桶陈酿期间采用不同比例(10%、20%、30%、40%)美乐葡萄酒进行二元混酿,陈酿12个月后分析混酿葡萄酒的理化指标、色泽参数、酚类物质及挥发性成分含量,并结合感官量化品评法对葡萄酒感官特征进行描述分析。结果表明,美乐葡萄酒的添加可以显著降低赤霞珠葡萄酒的酒精体积分数、总酸含量和色度值;美乐占比为10%和20%混酿葡萄酒的香气物质含量较高,约为赤霞珠葡萄酒的1.22倍,美乐占比20%的葡萄酒有助于2-糠酸乙酯、苹果酸二乙酯和苯甲醇等花果香物质的生成;感官分析表明,美乐占比20%的混酿葡萄酒具有更好的口感协调性和单宁细腻度,整体评分最高。综上,20%美乐混酿对赤霞珠葡萄酒色泽、香气和感官品质改善效果最好。本研究可为混酿葡萄酒生产提供理论支持。

关键词：葡萄酒混酿酚类物质挥发性成分感官评价

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锌铝镁镀层在加热过程中的组织和耐蚀性

钢铁 2024年第7期59卷 139-149,168页

作者：刘广会韩赟刘全利徐呈亮蒋光锐陈建军首钢集团有限公司技术研究院北京100043

锌铝镁镀层相对于纯锌镀层具有更好的耐蚀性,结合其特有的划伤自愈、切口保护等特点受到越来越多的钢铁生产企业及下游用户的重视,尤其在材料服役条件较为严苛的环境,客户采用该新型镀层的愿望较为强烈。锌铝镁镀层钢板在使用过程中会... 详细信息

锌铝镁镀层相对于纯锌镀层具有更好的耐蚀性,结合其特有的划伤自愈、切口保护等特点受到越来越多的钢铁生产企业及下游用户的重视,尤其在材料服役条件较为严苛的环境,客户采用该新型镀层的愿望较为强烈。锌铝镁镀层钢板在使用过程中会遇到热加工和热处理,最常见的是焊接和切割。因此研究锌铝镁镀层在不同温度区间的性能稳定性越来越受到关注。为了探究锌铝镁镀层在温度变化过程中组织和性能的变化,更好地提高镀层耐热性能,研究了不同铝含量的锌铝镁镀层(Zn1Al1Mg、Zn55Al1Mg)在不同的加温温度(300、500、700℃)进行加热,并随炉保温10 min之后镀层内部的组织变化以及对物理和化学性能产出的影响。通过相图计算预测了保温之前镀层的析出相,通过电镜表征热处理后镀层的截面组织和表面组织的形貌,对各个不同的区域进行电镜自带的EDS的成分检测;同时,对镀层中不同相的组成进行了XRD的测试;对不同热处理工艺的试样进行维氏硬度的测试;对试样的耐腐蚀性能用电化学的方法来评估。结果表明,在加热到700℃的时候,Zn1Al1Mg和Zn55Al1Mg镀层的表面组织和截面组织的形貌都出现了很大的变化,对于Zn1Al1Mg镀层组织明显的分为2层,分别为Zn-Fe层和Fe-Zn层;对于Zn55Al1Mg的镀层组织,产生了从基体生长的柱状富铝相,在钢板和镀层的交界处密集生长;表面组织出现了疏松多孔的组织;电化学的结果显示,2种镀层的耐腐蚀性能都有所下降。维氏硬度的检测表明,2种镀层经过热处理后硬度都得到了提高。

关键词：锌铝镁镀层 Zn-Al-Mg-Fe四元相图耐腐蚀性热处理 Fe4Zn9

Small molecule-based immunomodulators for cancer therapy

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Acta Pharmaceutica Sinica B 2022年第12期12卷 4287-4308页

作者： Yinrong Wu Zichao Yang Kui cheng Huichang Bi jianjun chen Guangdong Provincial Key Laboratory of New Drug Screening NMPA Key Laboratory for Research and Evaluation of Drug MetabolismSchool of Pharmaceutical SciencesSouthern Medical UniversityGuangzhou 510515China

Immunotherapy has led to a paradigm shift in the treatment of *** cancer immunotherapies are mostly antibody-based,thus possessing advantages in regard to pharmacodynamics(e.g.,specificity and efficacy).However,they have limitations in terms of pharmacokinetics including long half-lives,poor tissue/tumor penetration,and little/no oral *** addition,therapeutic antibodies are immunogenic,thus may cause unwanted adverse ***,researchers have shifted their efforts towards the development of small molecule-based cancer immunotherapy,as small molecules may overcome the above disadvantages associated with ***,small molecule-based immunomodulators and therapeutic antibodies are complementary modalities for cancer treatment,and may be combined to elicit synergistic *** years have witnessed the rapid development of small molecule-based cancer *** this review,we describe the current progress in small molecule-based immunomodulators(inhibitors/agonists/degraders)for cancer therapy,including those targeting PD-1/PD-L1,chemokine receptors,stimulator of interferon genes(STING),Toll-like receptor(TLR),*** tumorigenesis mechanism of various targets and their respective modulators that have entered clinical trials are also summarized.

关键词： Cancer immunotherapy Small molecules Immunomodulators Inhibitors Agonists

Self-assembly and drug delivery behaviors of a novel thermo-sensitive block glycopolymer

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Chinese Science Bulletin 2010年第36期55卷 4187-4196页

作者： chen LiQiong ZHANG LiMing chen jianjun YANG Jian LI RongXian DSAMP Laboratory and PCFM Laboratory School of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou 510275 China Research Institute of Tsinghua University in Shenzhen Shenzhen 518057 China

A novel thermo-sensitive block glycopolymer based on peracetylated maltoheptaose (AcMH) and poly(2-ethyl-2-oxazoline) (PEtOz) was synthesized for the first time and characterized by hydrogen nuclear magnetic resonance (1H NMR) spectroscopy and gel permeation chromatograph (GPC) analyses. To obtain such a block polymer, the dihydroxyl poly(2-ethyl-2-oxazoline) homopolymer (OH-PEtOz-OH) was first synthesized by cationic ring-opening polymerization of 2-ethyl-2-oxazoline (EtOz), and then coupled with the peracetylated maltoheptaose having a free hydroxyl group at the reducing end (AcMH-OH) prepared from β-cyclodextrin. It was found that the obtained block polymer could self-assemble into nanosize spherical micelles with a distinct core-shell structure in aqueous solution triggered by its amphiphilic character without any organic solvent. The model drug indomethacin (IND) was efficiently loaded into the resultant polymeric micelles, which was confirmed by 1H NMR spectra, transmission electron microscope (TEM) and dynamic light scattering (DLS) techniques. The release behavior of IND loaded micelles was well in response to the environmental temperature change. It is suggested that the resulting micelles might be a potential targeted carrier for drug delivery.

关键词：自组装行为药物输送温敏凝胶渗透色谱仪透射电子显微镜嵌段聚合物胶束结构核磁共振光谱