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Spatio-temporal variation of soil CO_(2) concentration in Loess Area of northwestern Shanxi Province,China

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Research in Cold and Arid Regions 2022年第3期14卷 196-211页

作者： TianJie Shao ZhiPing Xu LianKai Zhang RuoJin Wang junjie niu MingYu Shao College of Geography Science and Tourism Shaanxi Normal UniversityXi'anShaanxi 710062China Institute of Karst Geology Chinese Academy of Geological SciencesGuilinGuangxi 541000China Research Center for Scientific Development in Fenhe River Basin Taiyuan Normal UniversityTaiyuanShanxi 030001China SNNU-JSU Joint Research Center for Nano-environment Science and Health Shaanxi Normal UniversityXi'anShaanxi 710062China

CO_(2) released by soil serves as an important link between terrestrial ecosystems and atmospheric CO_(2), whose small chang‐es may significantly affect the global carbon cycle. In order to reveal the spatio-temporal variations of CO_(2) concentrations in deep loess, this paper takes Qingliangsi Gully watershed in northwestern Shanxi Province, China as an example to sys‐tematically study soil CO_(2)concentration and its spatio-temporal variations and carbon sink significance under different watershed locations and different land use types. Results show that: (1) The release potential of the loess soil is larger in the depth range of 2 m, which is much more likely to be the CO_(2) release area. (2) Grassland and forest are more advanta‐geous in terms of soil microbial activity and soil carbon reserve compared with farmland. In addition, the change of land use type from farmland to grassland can increase soil organic carbon reserve, which is of far-reaching significance to the global carbon cycle. This is especially true in an area like the Loess Plateau with densely covered hills, gullies, and serious soil erosion in an area of 64×104 km2. (3) In the study area, the diurnal concentration of soil CO_(2) at different depths shows a weak "high-low-high-low" trend from 08:00 to 07:00 next day;and in deep soil it has a lag time compared with the daily change of temperature, generally about 4−12 h, which may be caused largely by the more compact loess structure. It is worth pointing out that the Loess Plateau in China, with a thickness of the loess of tens to hundreds of meters, has the most abundant soil resources in the world, and also stores a large amount of terrestrial soil carbon, which carries the hope of promoting the research of global carbon cycle.

关键词： soil CO_(2)concentration China Loess Plateau carbon sink function release potential

Chronology of the Holocene loess-paleosol section and its deposition and pedogenesis on the south of Chinese Loess Plateau

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Journal of Geographical Sciences 2008年第4期18卷 425-442页

作者： JIA Yaofeng HUANG Chunchang PANG Jiangli niu junjie College of Tourism and Environment Shaanxi Normal University Xl＇an 710062 China North University for Nationalities School of Management Ylnchuan 750021 China

Optically stimulated luminescence （OSL） dating for polymlneral fine-grained loess samples, collected in Laoguantai （LGT） section on the south of the Chinese Loess Plateau, was made by application of single-aliquot regenerative-dose （SAR） protocol. A ＇Double-SAW procedure in which aliquots are subjected to both infrared （IR） and blue stimulations was used and two sets of equivalent dose （De） determinations were produced and assumed to relate predominantly to feldspathic and quartz fine grain populations respectively, The OSL ages estimated from IRSL signals are smaller than those estimated from [post-IR] OSL signals due to the anomalous fading of feldspar IR signals, based on fading experiment, The young ages of the samples near ground surface may be originated from the post-depositional disturbance by the intensifying humanity＇s cultivation since 3.0 ka BP in the Guanzhong Basin, south of the Chinese Loess Plateau. Based on OSL dating, as well as field observations and stratigraphic correlation, we determine the chronology of the LGT Ioess-paleosol sequence. In combination with climate proxy records, it is indicated that aeolian loess deposition and pedogenesis underwent polyphase changes during the Holocene, likely to have been driven by shifts in the East Asian monsoon. This suggests that aeolian loess deposition is episodic and highly variable, with contributions from non-aeolian processes such as alluvial deposition found in the area.

关键词： Chinese Loess Plateau loess deposition and pedogenesis East Asian monsoon Hoiocene

Punicalagin ameliorates collagen-induced arthritis by downregulating M1 macrophage and pyroptosis via NF-κB signaling pathway

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Science China(Life Sciences) 2022年第3期65卷 588-603页

作者： Gaoran Ge Jiaxiang Bai Qing Wang Xiaolong Liang Huaqiang Tao Hao Chen Minggang Wei junjie niu Huilin Yang Yaozeng Xu Yuefeng Hao Yi Xue Dechun Geng Department of Orthopaedics The First Affiliated Hospital of Soochow UniversitySuzhou 215006China Department of Traditional Chinese Medicine The First Affiliated Hospital of Soochow UniversitySuzhou 215006China Orthopaedics and Sports Medicine Center Suzhou Municipal Hospital(North District)Nanjing Medical University Affiliated Suzhou HospitalSuzhou 215006China Department of Orthopaedics Changshu Hospital Affiliated to Nanjing University of Traditional Chinese MedicineSuzhou 215500China

Rheumatoid arthritis(RA)is a chronic inflammatory disease that eventually leads to *** cell infiltration,severe joint breaking and systemic bone loss are the main clinical *** this study,we established a collagen-induced arthritis(CIA)model and found a large number of M1 macrophages and pyroptosis,which are important sources of proinflammatory ***(PUN)is an active substance extracted from pomegranate *** found that it inhibited joint inflammation,cartilage damage and systemic bone destruction in CIA *** effectively alleviated the high expression of inflammatory cytokines in synovial tissue in *** treatment shifted macrophages from the M1 phenotype to the M2 phenotype after stimulation with lipopolysaccharide(LPS)and interferon(IFN)-γ.The expression of inducible nitric oxide synthase(i NOS)and other proinflammatory cytokines released by M1 macrophages was decreased in the PUN treatment ***,simultaneously,the expression of markers of anti-inflammatory M2 macrophages,such as arginase(Arg)-1 and interleukin(IL)-10,was *** addition,PUN treatment attenuated pyroptosis by downregulating the expression of NLRP3 and caspase-1,thereby preventing inflammatory cell death resulting from the release of IL-1βand ***,PUN inhibited the activation of receptor activators of the nuclear factor-κB(NF-κB)signaling pathway,which contributes to M1 polarization and pyroptosis of *** concluded that PUN ameliorated pathological inflammation by inhibiting M1 phenotype polarization and pyroptosis and has great potential as a therapeutic treatment for human RA.

关键词： rheumatoid arthritis pomegranate M1 macrophage pyroptosis

Bio-clickable mussel-inspired peptides improve titanium-based material osseointegration synergistically with immunopolarization-regulation

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Bioactive Materials 2022年第3期7卷 1-14页

作者： Jie Sun Yingkang Huang Huan Zhao junjie niu Xuwei Ling Can Zhu Lin Wang Huilin Yang Zhilu Yang Guoqing Pan Qin Shi Department of Orthopaedics The First Affiliated Hospital of Soochow UniversityOrthopaedic Institute of Soochow University899 PinghaiSuzhouJiangsu215031China Affiliated Dongguan Hospital Southern Medical UniversityNo.3 Wandao RoadDongguanGuangdong523059China Guangdong Provincial Key Laboratory of Shock and Microcirculation No.1023 Shatai RoadGuangzhouGuangdong510080China Institute for Advanced Materials School of Materials Science and EngineeringJiangsu University301 Xuefu RoadZhenjiangJiangsu212013China

Upon the osteoporotic condition,sluggish osteogenesis,excessive bone resorption,and chronic inflammation make the osseointegration of bioinert titanium(Ti)implants with surrounding bone tissues difficult,often lead to prosthesis loosening,bone collapse,and implant *** this study,we firstly designed clickable mussel-inspired peptides(DOPA-N3)and grafted them onto the surfaces of Ti materials through robust catechol-TiO2 coordinative ***,two dibenzylcyclooctyne(DBCO)-capped bioactive peptides RGD and BMP-2 bioactive domain(BMP-2)were clicked onto the DOPA-N3-coated Ti material surfaces via bio-orthogonal *** characterized the surface morphology and biocompatibility of the Ti substrates and optimized the osteogenic capacity of Ti surfaces through adjusting the ideal ratios of BMP-2/RGD at 3:*** vitro,the dual-functionalized Ti substrates exhibited excellent promotion on adhesion and osteogenesis of mesenchymal stem cells(MSCs),and conspicuous immunopolarization-regulation to shift macrophages to alternative(M2)phenotypes and inhibit inflammation,as well as enhancement of osseointegration and mechanical stability in osteoporotic *** summary,our biomimetic surface modification strategy by bio-orthogonal reaction provided a convenient and feasible method to resolve the bioinertia and clinical complications of Ti-based implants,which was conducive to the long-term success of Ti implants,especially in the osteoporotic or inflammatory conditions.

关键词： Titanium implant Clickable mussel-inspired peptide Bio-orthogonal reaction Osseointegration Immunopolarization

维普期刊数据库评论

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基于相似度建模的永磁牵引列车健康优化控制

仪器仪表学报 2017年第2期38卷 480-486页

作者：牛刚江俊杰同济大学铁道与城市轨道交通研究院上海201804

为了保障永磁牵引列车退磁故障发生时的安全性,并缓解由此导致的电制动力下降及闸瓦磨耗加剧问题,提出了一种基于相似度建模(SBM)的健康优化控制方法,该方法通过在线监测数据与历史数据的相似度运算,自适应地估计剩余磁通量并生成最优... 详细信息

为了保障永磁牵引列车退磁故障发生时的安全性,并缓解由此导致的电制动力下降及闸瓦磨耗加剧问题,提出了一种基于相似度建模(SBM)的健康优化控制方法,该方法通过在线监测数据与历史数据的相似度运算,自适应地估计剩余磁通量并生成最优的空气制动F-v特性曲线。以西门子Syntegra永磁同步电机牵引系统为例,对多种工况下的退磁监测和健康优化控制效果进行了仿真验证,在退磁估计准确性、相对磨耗优化和安全性保障等方面取得了预期的效果。

关键词：永磁同步电机预测与健康管理优化控制基于相似度建模

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纪昀与康德伦理思想探略

社会科学 2005年第2期 83-87页

作者：牛俊杰湖北大学哲学研究所

生活在同一时代的纪昀和康德 ,各自给出了善恶的判定标准 ,一个可称之为“问心无愧”原则 ,一个可称之为“由己及人”原则 ,两人可谓“心有灵犀一点通”。本文试图从康德的《道德形而上学原理》和《实践理性批判》以及纪昀的《阅微草堂... 详细信息

生活在同一时代的纪昀和康德 ,各自给出了善恶的判定标准 ,一个可称之为“问心无愧”原则 ,一个可称之为“由己及人”原则 ,两人可谓“心有灵犀一点通”。本文试图从康德的《道德形而上学原理》和《实践理性批判》以及纪昀的《阅微草堂笔记》中探寻他们的伦理思想。

关键词：纪昀康德善恶道德律

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气冷喷油杆隔热套高度对混合扩压器性能影响

北京航空航天大学学报 2016年第6期42卷 1099-1106页

作者：刘友宏周开福牛俊杰北京航空航天大学能源与动力工程学院北京100083

针对一种带气冷喷油杆的混合扩压器,基于Navier-Stokes方程组建立了流场三维数值计算模型,研究了气冷喷油杆的隔热套高度对一体化混合扩压器流场、流阻特性和混合特性的气动热力性能影响规律。结果表明:隔热套高度对混合扩压器热混合效... 详细信息

针对一种带气冷喷油杆的混合扩压器,基于Navier-Stokes方程组建立了流场三维数值计算模型,研究了气冷喷油杆的隔热套高度对一体化混合扩压器流场、流阻特性和混合特性的气动热力性能影响规律。结果表明:隔热套高度对混合扩压器热混合效率影响不大,总体变化范围小于0.008;随着隔热套高度的增加,静压恢复系数逐渐减小,流阻系数和压力损失系数逐渐增大;在混合扩压器出口截面处,总压恢复系数随隔热套高度增加而逐渐减小,且总体变化范围较小,由0.991 1减小到0.990 7。

关键词：气冷喷油杆隔热套高度混合扩压器流阻特性混合特性

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多孔碳柱撑膨润土的制备与表征(英文)

硅酸盐学报 2008年第7期36卷 1008-1012页

作者：张增志杨春卫牛俊杰中国矿业大学(北京)生态功能材料研究所北京100083

用十六烷基三甲基溴化铵和苄基三甲基氯化铵改性膨润土制备了多孔碳柱撑膨润土。用Fourier变换红外光谱仪、扫描电子显微镜和氮气吸附–脱附、热分析系统地研究了有机改性剂对多孔材料性能的影响。结果表明:膨润土微粒与有机改性剂以共... 详细信息

用十六烷基三甲基溴化铵和苄基三甲基氯化铵改性膨润土制备了多孔碳柱撑膨润土。用Fourier变换红外光谱仪、扫描电子显微镜和氮气吸附–脱附、热分析系统地研究了有机改性剂对多孔材料性能的影响。结果表明:膨润土微粒与有机改性剂以共价键和离子嵌入2种形式结合;多孔碳柱撑膨润土的微观形貌呈针片状,最可几孔径分布大约在1.7nm;多孔材料的主要结构是由碳化的大粒子柱撑而构建的二维孔径,烧结后的有机黏土热稳定性大大提高。

关键词：碳柱撑膨润土纳米多孔材料二维孔径表面活性剂十六烷基三甲基溴化铵苄基三甲基氯化铵

复杂气象条件下考虑结冰风险的无人机飞行策略

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航空学报 2023年第1期44卷 114-130页

作者：郭琪磊桑为民牛俊杰袁烨西北工业大学航空学院西安710072 中国民用航空飞行学院工程技术训练中心广汉618307 中国空气动力研究与发展中心结冰与防除冰重点实验室绵阳621000 中国商用飞机有限责任公司上海飞机设计研究院上海201210

为解决无人机在复杂气象条件下易受结冰影响而威胁其飞行安全的问题,提出了一种考虑结冰风险的无人机航迹规划方法。首先,构建基于中尺度WRF(Weather Research and Forecasting)模式的结冰气象预测模型,通过最佳参数化方案组合的结冰气... 详细信息

为解决无人机在复杂气象条件下易受结冰影响而威胁其飞行安全的问题,提出了一种考虑结冰风险的无人机航迹规划方法。首先,构建基于中尺度WRF(Weather Research and Forecasting)模式的结冰气象预测模型,通过最佳参数化方案组合的结冰气象模拟获得模拟时段内海南乐东地区的温度、压力、液态水含量(LWC)空间分布及时序变化。其次,构建基于代理模型的水滴收集质量快速预测方法。在获取美国联邦航空条例(FAR)25部附录C中连续最大结冰条件下40个采样点处水滴收集质量分布的基础上,利用本征正交分解(POD)降阶模型和Kriging插值算法,建立温度、压力、LWC、平均有效水滴直径(MVD)等结冰气象参数与水滴收集质量之间的代理模型,可快速预测出目标区域内水滴收集质量的空间分布与时序变化。最后,根据飞机结冰强度划分等级,以不同结冰强度下水滴收集质量阈值为结冰安全约束,利用基于粒子群优化(PSO)的结冰容限航迹规划方法进行考虑结冰风险的无人机飞行策略研究。研究结果表明:利用WRF模式可获得温度、压力、LWC等结冰气象参数,预测值与观测值匹配良好;基于POD降阶模型和Kriging插值算法,构建的气象参数与水滴收集质量间代理模型可快速准确地获取目标区域内水滴收集质量的空间分布与时序变化;基于PSO的结冰容限航迹规划方法可在不同结冰安全约束条件下,规划出无人机最优航迹。

关键词：无人机结冰气象 Weather Research and Forecasting(WRF) 代理模型水滴收集质量快速预测航迹规划粒子群优化