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生物质的热解过程及其动力学规律

煤炭学报 2006年第4期31卷 501-505页

作者：程世庆尚琳琳张海清山东大学能源与动力工程学院山东济南250061

采用热重分析法(TGA)对几种常见天然生物质(稻秆、麦秆、玉米秆)和其衍生物木质素、造纸废液颗粒等的热解过程及其动力学规律进行了研究.实验中加热速率分别为10,20,30℃/m in,终温为850℃.热解在氮气气氛下进行,并用高纯氮气作为保护气... 详细信息

采用热重分析法(TGA)对几种常见天然生物质(稻秆、麦秆、玉米秆)和其衍生物木质素、造纸废液颗粒等的热解过程及其动力学规律进行了研究.实验中加热速率分别为10,20,30℃/m in,终温为850℃.热解在氮气气氛下进行,并用高纯氮气作为保护气体.实验结果表明:天然生物质的非等温热解只有1个剧烈失重阶段,而木质素和造纸废液颗粒存在2个剧烈失重阶段.生物质比煤的热解起始温度低,热解速度快.随升温速率的提高,生物质的最大热解速度提高,对应的峰值温度升高,最终失重率呈下降趋势.生物质的热解机理满足三维扩散Jander方程,且随着升温速率的提高,其活化能增大.

关键词：生物质热解过程动力学热重分析

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地下水污染源解析方法研究进展

地质通报 2024年第1期43卷 153-162页

作者：冉泽宇贾永锋姜永海史浙明尚长健臧永歌陈帆廉新颖中国环境科学研究院/环境基准与风险评估国家重点实验室北京100012 中国地质大学(北京)水资源与环境学院北京100083 中国环境科学研究院/国家环境保护地下水污染模拟与控制重点实验室北京100012 中国核电工程有限公司北京100840

地下水污染具有隐蔽性,污染过程缓慢且难以治理,近年来中国高度重视地下水环境保护工作,作为支撑“以防为主”保护理念的地下水污染源解析技术研究已成为地下水污染防治领域的研究热点。介绍了国内外地下水污染源解析方面的主要技术方法... 详细信息

地下水污染具有隐蔽性,污染过程缓慢且难以治理,近年来中国高度重视地下水环境保护工作,作为支撑“以防为主”保护理念的地下水污染源解析技术研究已成为地下水污染防治领域的研究热点。介绍了国内外地下水污染源解析方面的主要技术方法,包括同位素法、荧光光谱法、地质统计学法、主成分分析法、正定矩阵因子分析模型、自组织映射技术6种常用方法的基本原理及在地下水污染识别领域的应用和研究动态,总结了这些方法的优缺点与适用性,并就上述方法在地下水污染研究中的应用前景和发展趋势进行了展望。

关键词：地下水污染源解析同位素法正定矩阵因子分析模型自组织映射技术

Notes on Strongly n-Gorenstein Projective, Injective and Flat Modules

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Chinese Quarterly Journal of Mathematics 2012年第3期27卷 389-396页

作者： shang Wen-liang Department of Mathematics Northwest Normal University Lanzhou 730070 China

In this paper, we mainly investigate some properties of strongly n-Gorenstein projective, injective and flat modules under the extension of rings, which mainly including excellent extensions, morita equivalences, poly... 详细信息

关键词： excellent extensions strongly n-Gorenstein projective modules strongly nGorenstein injective modules strongly n-Gorenstein flat modules

Clinicopathological Features and Prognostic Value of KRAS/NRAS/BRAF Mutations in Colorectal Cancer Patients of Central China

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Current Medical Science 2021年第1期41卷 118-126页

作者： Xiao-na CHANG Fu-mei shang Hong-yu JIANG Chen CHEN Zhe-yan ZHAO Sheng-he DENG Jun FAN Xiao-chuan DONG Ming YANG Yan li Kai-lin CAI li liU Hong-li liU Xiu NIE Department of Pathology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Cancer Center Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Department of Epidemiology and Biostatistics the Ministry of Education Key Lab of Environment and HealthSchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Gastrointestinal Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China

The incidence of colorectal cancer(CRC)is increasing in China,with high ***,we aimed to evaluate the latest clinicopathological features and prognostic value of the KRAS/NRAS/BRAF mutation status in CRC patients in Central *** clinical data of 1549 CRC patients with stage I-IV disease diagnosed at Union Hospital,Tongji Medical College of Huazhong University of Science and Technology from 2015 to 2017 were collected and analyzed ***/NRAS/BRAF mutations were detected by real-time quantitative polymerase chain reaction(q-PCR)in 410 CRC patients,with mutation frequencies of KRAS,NRAS and BRAF of 47.56%,2.93%and 4.15%,*** gene mutation status and clinicopathological characteristics of 410 patients with CRC who underwent qPCR were *** KRAS and BRAF gene mutations were related to the pathological differentiation and number of metastatic lymph *** BRAF gene mutation was also associated with cancer thrombosis in blood *** regression analysis showed that there was no statistically significant difference in the overall survival(OS)between patients with KRAS,NRAS mutants and wild-type CRC patients,while the BRAF gene mutation was negatively correlated with the OS rate of CRC *** is suggested that the BRAF gene mutation may be an independent risk factor for the prognosis of CRC.

关键词： colorectal cancer KRAS mutation NRAS mutation BRAF mutation prognosis

Effects of bump parameters on hypersonic inlet starting performance

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第10期23卷 807-819页

作者： shang-cheng XU Yi WANG Zhen-guo WANG Xiao-qiang FAN Bing XIONG College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Unstart is an unwanted flow phenomenon in a hypersonic inlet. When an unstart occurs, the captured airflow flowing through the engine significantly decreases with strong unsteady characteristics, which may lead to thrust loss or even combustor flameout. In this study, various bump configurations were designed to be integrated with a hypersonic inlet to improve its starting ability. A bump was defined as an integrated 3D compression surface installed upstream of the inlet entrance. The starting processes of these bump inlets were numerically simulated to investigate the effect laws and flow mechanisms of the bump parameters. Tests on bump height revealed that the starting performance could be significantly improved by increasing bump height, with the starting Mach number decreasing by 0.55 for the inlet with the highest bump. The high bump facilitates the side movement of the subsonic flow in the separation zone, which leads to a small separation bubble, thus accelerating the starting process. Further, the starting ability can be improved by designing a relatively wide bump, which results in a decline in the starting Mach number by 0.44. When the bump has the same or greater width compared with the airflow capture range, a growing spillage along the transverse direction can be formed so that the airflow in the separation bubble can be easily excluded, improving the starting ability.

关键词： Hypersonic inlet Bump Boundary layer flow Starting performance Large-scale separation bubble

Contributions to the Interannual Summer Rainfall Variability in the Mountainous Area of Central China and Their Decadal Changes

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Advances in Atmospheric Sciences 2020年第3期37卷 259-268页

作者： Kaiming HU Yingxue liU Gang HUANG Zhuoqi HE shang-Min LONG Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Joint Center for Global Change Studies(JCGCS) Beijing 100875China University of Chinese Academy of Sciences Beijing 100049China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China College of Oceanography Hohai UniversityNanjing 210098China

Using a high-resolution precipitation dataset,the present study detected that the mountainous area of central China(MACA)is a hotspot of ENSO’s impact on the summer rainfall *** analysis suggests that both ENSO and atmospheric forcing make contributions to the summer rainfall variability in *** dominant rainfall-related SST mode features as a seasonal transition from an El Niño-like warming in the preceding winter to a La Nina-like cooling in the following autumn,and it explains about 29%of the total variance of the rainfall during 1951–*** indicates that ENSO with a rapid phase transition is responsible for inducing summer rainfall anomalies in ***,an upperlevel circumglobal wave mode in the Northern Hemisphere during summer also explains about 29%of the summer rainfall *** of both the SST and the atmospheric modes have experienced interdecadal *** influence of the SST mode gradually increases and plays a dominant role in the recent decades,suggesting that ENSO with a rapid phase transition becomes more important for rainfall prediction in MACA.

关键词： summer rainfall ENSO atmospheric internal variability interdecadal change

Ordering Trees with Fixed Order and Matching Number by Laplacian Spectral Radius

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Journal of Mathematical Research and Exposition 2011年第3期31卷 381-392页

作者： shang Wang TAN College of Mathematics and Computational Science China University of Petroleum Shandong 257061 P. R. China

Let T（n,i） be the set of all trees with order n and matching number *** determine the third to sixth trees in T（2i ＋ 1,i） and the third to fifth trees in T（n,i） for n ≥ 2i ＋ 2 with the largest Laplacian spect... 详细信息

关键词： tree matching Laplacian spectral radius.

Regional tissue oxygen saturation as a predictor of post-spinal anesthesia hypotension for cesarean delivery

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Chinese Medical Journal 2021年第19期134卷 2353-2355页

作者： Hong Wei Han-Kun Tu shang-Long Yao Xi Wu Department of Anesthesiology Huazhong University of Science and Technology Union ShenZhen HospitalShenZhenGuangdong 518000China Department of Anesthesiology The 6th Affiliated Hospital of Shenzhen University Health Science CenterShenZhenGuangdong 518000China Department of Anesthesiology Institute of Anesthesiology and Critical Care MedicineUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China

Since the discovery of neuraxial blockade,spinal anesthesia has been frequently used for cesarean *** to an international consensus statement on hypotension management,Kinsella et al[1]reported the incidence of post-spinal anesthesia hypotension in parturient women to be as high as 70%to 80%.Post-spinal anesthesia hypotension is mainly caused by sympathetic vasomotor block,which results in reduced systemic vascular resistance,venous pooling in capacitance vessels,and decreased cardiac *** hypotension may lead to maternal and fetal adverse *** maternal hypotension may contribute to reduced uterus blood flow resulting in decreased placental perfusion and fetal hypoxia leading to acute fetal *** women having a positive preoperative stress test were associated with an increased risk of post-spinal anesthesia hypotension during cesarean delivery.[2]However,the sensitivity of the stress test for predicting post-spinal anesthesia hypotension was only 69%.[2]In clinical practice,non-invasive,reliable,and readily available techniques are still much in need to predict the incidence of hypotension after spinal anesthesia as well as to improve the management of spinal anesthesia-induced hypotension for cesarean delivery.

关键词： anesthesia hypotension fetal

Organophosphine bearing multiple hydrogen-bond donors for asymmetric Michael addition reaction of 1-oxoindane-2-carboxylic acid ester via dual-reagent catalysis

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Chinese Chemical Letters 2021年第2期32卷 708-712页

作者： Haoran Hong Hongyu Wang Changwu Zheng Gang Zhao Yongjia shang Key Laboratory of Functionalized Molecular Solids.Ministry of Education Anhui Key Laboratory of Molecule-Based Materials(State Key Laboratory Cultivation Base)College of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241000China Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic ChemistryCenter for Excellence in Molecular SynthesisChinese Academy of SciencesShanghai 200032China College of Chemistry Chemical Engineering and Materials Science.Shandong Normal UniversityJi'nan 250014China

Multiple hydrogen bonds containing nucleophilic phosphines derived from dipeptide dual-reagents catalyzed asymmetric Michael addition reactions between indene esters and activated olefins in high yields and good to excellent enantioselectivities under mild reaction *** success of current highly selective reactions should provide inspiration for expansion to other reactions and would open up new paradigms for the synthesis of indanone derivatives bearing chiral quaternary carbon centers.

关键词： Dual-reagent catalysis Michael addition reaction Multiple hydrogen bonds Chiral quaternary carbon centers