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由残存瓦斯量确定煤层瓦斯压力及含量的方法

采矿与安全工程学报 2011年第2期28卷 315-318页

作者：吴冬梅程远平安丰华中国矿业大学煤矿瓦斯治理国家工程研究中心江苏徐州221008

系统研究了突出煤样的破碎粒度、瓦斯压力对突出煤层残存瓦斯含量的影响.实验结果表明,煤的破碎粒度对残存瓦斯含量有显著影响,粒径越大,残存瓦斯量越大,当煤样粒径较大或较小时,煤样的残存瓦斯含量均趋于恒定.利用相同暴露时间下同一... 详细信息

系统研究了突出煤样的破碎粒度、瓦斯压力对突出煤层残存瓦斯含量的影响.实验结果表明,煤的破碎粒度对残存瓦斯含量有显著影响,粒径越大,残存瓦斯量越大,当煤样粒径较大或较小时,煤样的残存瓦斯含量均趋于恒定.利用相同暴露时间下同一粒径煤样得出残存瓦斯含量与煤层瓦斯压力和瓦斯含量均存在幂函数关系.依据此规律,可在测定煤层的残存瓦斯量后,结合已确定的煤样残存瓦斯量与瓦斯压力和瓦斯含量关系推算出煤层的瓦斯压力及瓦斯含量.该方法的提出为煤层瓦斯压力和瓦斯含量的确定特别是对突出煤层提出了一种新的可靠便捷方法,并在祁南煤矿现场得到了验证.

关键词：突出煤层残存瓦斯含量瓦斯压力瓦斯含量

基于价值评估的川滇生态屏障区生境质量时空演变及其影响因素

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生态与农村环境学报 2022年第11期38卷 1377-1387页

作者：郑可君李琛吴映梅高彬嫔武燕李婵云南师范大学地理学部云南昆明650500 云南省社会科学院云南昆明650034

重要生态功能区肩负着维持生态系统循环和保护生物多样性的重任,揭示重要生态功能区生境质量的时空演变特征及影响因素对维护区域生态安全、促进人与自然和谐发展具有重要意义。综合生态系统服务价值、生境活力和生境威胁构建生境质量... 详细信息

重要生态功能区肩负着维持生态系统循环和保护生物多样性的重任,揭示重要生态功能区生境质量的时空演变特征及影响因素对维护区域生态安全、促进人与自然和谐发展具有重要意义。综合生态系统服务价值、生境活力和生境威胁构建生境质量评估模型,对2000—2018年川滇生态屏障区生境质量进行分析,并运用地理探测器模型揭示其影响因素。结果表明:(1)2000—2018年川滇生态屏障区生境质量整体水平持续上升,上升区域主要分布在研究区南部;生境质量等级以中等、较高和较低为主,生境质量等级转移变化以较低转为中等和中等转为较高为主。(2)2000—2018年川滇生态屏障区生境质量稳定发展区域面积占比(45.97%)>生境质量向好发展区域面积占比(43.46%)>生境质量向差发展区域面积占比(10.57%),建议重视生境质量向差发展区域,避免生境质量进一步恶化。(3)2000—2018年川滇生态屏障区生境质量演变过程主要受高程、气温、地形起伏度和距水域距离等自然因子的影响,但人口密度、GDP、距城镇距离和夜间灯光强度等人为因子的影响程度也在不断增强。与此同时,自然因子与人为因子的交互影响程度大于单因子影响程度。研究结果有助于揭示川滇生态屏障区生境质量时空演变过程,为国家重要生态功能区建设及管理提供参考。

关键词：价值评估生境质量影响因素川滇生态屏障区

四气门直喷式柴油机进气过程缸内流场的模拟研究

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上海交通大学学报 2000年第9期34卷 1293-1297页

作者：吴志军孙济美黄震上海交通大学动力与能源工程学院上海200030 吉林工业大学汽车工程学院长春130025

利用缸内三维流场测量装置 ,运用热线风速仪在稳流模拟试验台上研究了四气门直喷式柴油机进气过程的缸内流场特性 ,并与两气门直喷式柴油机进行了比较 ,揭示了四气门直喷式柴油机进气涡流的形成过程及气门开度对其影响的变化规律 .两气... 详细信息

利用缸内三维流场测量装置 ,运用热线风速仪在稳流模拟试验台上研究了四气门直喷式柴油机进气过程的缸内流场特性 ,并与两气门直喷式柴油机进行了比较 ,揭示了四气门直喷式柴油机进气涡流的形成过程及气门开度对其影响的变化规律 .两气门直喷式柴油机进气涡流主要由进气门轴线至气缸轴线附近的强气流产生 ,缸内主涡流出现在进气门下方 ,副涡流较弱 ;四气门直喷式柴油机的进气涡流主要由气缸周边处的强气流产生 ,缸内主涡流出现在两进气道气门的下方 ,随气门开度的增大而增强 ,副涡流出现在远离进气门的一边。

关键词：柴油机四气门进气涡流热线测速

Polymorphisms of alcohol dehydrogenase 2 and aldehyde dehydrogenase 2 and colorectal cancer risk in Chinese males

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World Journal of Gastroenterology 2008年第32期14卷 5078-5083页

作者： Chang-Ming Gao Toshiro Takezaki Jian-Zhong wu Xiao-mei Zhang Hai-Xia Cao Jian-Hua Ding Yan-Ting Liu Su-Ping Li Jia Cao Keitaro Matsuo Nobuyuki Hamajima Kazuo Tajima Division of Epidemiology Jiangsu Provincial Institute of Cancer Research 42 Baiziting Nanjing 210009 Jiangsu Province China Department of International Island and Community Medicine Kagoshima University Graduate School of Medical and Dental Sciences 8-35-1 Sakuragaoka Kagoshima 890-8544 Japan Hygiene Toxicology Department Third Military Medical University Preventive medicine college 30 Gaotanyan Avenue Shapingba District Chongqing 400038 China Division of Epidemiology and Prevention Aichi Cancer Center Research Institute Nagoya 464-8681 Japan Department of Preventive Medicine Biostatistics and Medical Decision Making Nagoya University School of Medicine Nagoya 466-8550 Japan

AIM: To evaluate the relationship between drinking and polymorphisms of alcohol dehydrogenase 2 (ADH2) and/or aldehyde dehydrogenase 2 (ALDH2) for risk of colorectal cancer (CRC) in Chinese males. METHODS: A case-control study was conducted in 190 cases and 223 population-based controls. ADH2 Arg47His (G-A) and ALDH2 Glu487Lys (G-A)genotypes were identified by PCR and denaturing high-performance liquid chromatography (DHPLC). Information on smoking and drinking was collected and odds ratio (OR) was estimated. RESULTS: The ADH2 A/A and ALDH2 G/G genotypes showed moderately increased CRC risk. The age- and smoking-adjusted OR for ADH2 A/A relative to G/A and G/G was 1.60 (95% CI=1.08-2.36), and the adjusted OR for ALDH2 G/G relative to G/A and A/A was 1.79 (95% CI=1.19-2.69). Signif icant interactions between ADH2, ALDH2 and drinking were observed. As compared to the subjects with ADH2 G and ALDH2 A alleles, those with ADH2 A/A and ALDH2 G/G genotypes had a signif icantly increased OR (3.05, 95% CI= 1.67-5.57). The OR for CRC among drinkers with the ADH2 A/A genotype was increased to 3.44 (95% CI= 1.84-6.42) compared with non-drinkers with the ADH2 G allele. The OR for CRC among drinkers with the ALDH2 G/G genotype was also increased to 2.70 (95% CI= 1.57-4.66) compared with non-drinkers with the ALDH2 A allele. CONCLUSION: Polymorphisms of the ADH2 and ALDH2 genes are significantly associated with CRC risk. There are also signifi cant gene-gene and gene- environment interactions between drinking and ADH2 and ALDH2 polymorphisms regarding CRC risk in Chinese males.

关键词： Alcohol dehydrogenase 2 Aldehydede hydrogenase 2 Gene polymorphisms Alcohol drinking Colorectal cancer

2,6-二甲氧基-2-嘧啶氧基-N-芳基苄胺衍生物的酸催化Smiles重排反应动力学

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物理化学学报 2016年第2期32卷 422-428页

作者：张培志叶美君胡伟莲吴军浙江科技学院生物与化学工程学院杭州310023 浙江科技学院浙江省废弃物生物质循环利用与生态处理技术重点实验室杭州310023 中华全国供销合作总社杭州茶叶研究院杭州310016 浙江大学化学系杭州310027

研究了酸催化下的2,6-二甲氧基-2-嘧啶氧基-N-芳基苄胺衍生物Smiles重排反应的动力学,考察了盐酸的初始浓度、溶剂、反应温度和取代基对反应速率的影响。结果表明,盐酸的初始浓度增加,重排反应速率加快;在单一溶剂中反应速率的顺序为:甲... 详细信息

研究了酸催化下的2,6-二甲氧基-2-嘧啶氧基-N-芳基苄胺衍生物Smiles重排反应的动力学,考察了盐酸的初始浓度、溶剂、反应温度和取代基对反应速率的影响。结果表明,盐酸的初始浓度增加,重排反应速率加快;在单一溶剂中反应速率的顺序为:甲醇>乙醇>二甲基亚砜>乙腈,而在甲醇/水(1:1,V/V)的混合溶剂中反应速率明显增加,其表观反应速率常数(k_(obs))值是甲醇溶剂中的5.27倍;在25-45℃温度范围内,各衍生物的反应速率随着温度的升高而加快,其活化能(73.99-76.92 kJ·mol^(-1))、活化焓(71.57-74.38 kJ·mol^(-1))及Gibbs自由能(81.51-85.77 kJ·mol^(-1))数值相近,仅活化熵(-24.38--47.11 J·K^(-1)·mol^(-1))有一定的差别;取代基常数和表观速率常数之间呈现一定的线性关系,环上吸电子基团的存在有利于反应速率的提高;实验验证了反应机理的合理性。

关键词：动力学反应机理 2,6-二甲氧基-2-嘧啶氧基-N-芳基苄胺衍生物 Smiles重排酸催化反应

PTEN-L promotes type I interferon responses and antiviral immunity

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Cellular & Molecular Immunology 2018年第1期15卷 48-57页

作者： Yuanyuan Cao Hongyun Wang Liu Yang Zhen Zhang Chenlin Li Xu Yuan Lang Bu Lang Chen Yu Chen Chun-mei Li Deyin Guo Modern Virology Research Center College of Life SciencesWuhan UniversityWuhan430072China School of Basic Medical Sciences Wuhan UniversityWuhan430072China Laboratory for Medical Virology School of MedicineSun Yat-sen UniversityGuangzhou510080China

Phosphatase and tensin homolog deleted on chromosome ten(PTEN)is a well-known tumor suppressor that acts as a dual-specificity phosphatase and is frequently mutated in human *** previous work has demonstrated that PTEN also plays a vital role in type I interferon responses and antiviral innate ***,a translational variant of PTEN with a long N-terminal extension(PTEN-L)has been discovered that is secreted into the extracellular environment and enters recipient cells,where it exerts a phosphatase function antagonistic to PI3K/Akt signaling and *** this study,we demonstrate that PTEN-L promotes type I interferon responses and antiviral innate immunity during viral infection in a phosphatase activity-dependent *** with canonical PTEN,PTEN-L also exerts its antiviral function when it is applied exogenously in protein *** finding was confirmed in cell cultures and mouse infection ***,PTEN-L enhances the responses of both type I interferon and proinflammatory cytokines,thus suggesting that PTEN-L might possess additional functions compared with those of ***,the antiviral function of PTEN-L may open an avenue for the use of PTEN-L in antiviral therapy,particularly in patients with PTEN-deficient tumors.

关键词： antiviral responses innate immunity PTEN PTEN-L type I interferon

Rapid Determination of Total Content of Five Major Anthraquinones in Rhei Radix et Rhizoma by NIR Spectroscopy

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Chinese Herbal Medicines 2017年第3期9卷 250-257页

作者： Hao Zhan Jing Fang Hong-wei wu Hong-jun Yang Hua Li Zhu-ju Wang Bin Yang Li-ying Tang mei-hong Fu Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences

Objective To establish a new method with near-infrared（NIR） spectroscopy to determine the total content of emodin, chrysophanol, rhein, aloeemodin, and physcion. NIR was used in this study to provide rapid and nondestructive analysis results. Methods In the first place, HPLC was used to measure the total content of emodin, chrysophanol, rhein, aloe-emodin and physcion in Rhei Radix et Rhizoma（RR） as a reference. In the second place, the spectral regions, regression methods, pretreatment methods, and partial least squares（PLS） factors were compared to increase the feasibility of the model. In the last, the root mean square error of calibration（RMSEC）, root mean square error of cross validation（RMSECV）, root mean square error of prediction（RMSEP）, and correlation coefficient（r） were used as assessment parameters. Results PLS with first derivative pretreatment in the ranges of 4242-5581 cm^（-1）, 5885-6233 cm^（-1） and 6394-7011 cm^（-1） provided the best results. The RMSEC and RMSEP obtained were 0.134 and 0.226 respectively. The according determination coefficients of the quantitative model were 0.99 and 0.94. Conclusion NIR spectroscopy as a quick and nondestructive analytical method may be used to determine the total content of emodin, chrysophanol, rhein, aloeemodin, and physcion for the quality control of RR.

关键词： near-infrared spectroscopy partial least squares quality control rapid determination Rhei Radix et Rhizoma

HTEM PO和TMPD调控下MMA可控/活性光聚合研究

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高等学校化学学报 2006年第1期27卷 192-195页

作者：刘晓暄任亚娥张婷韩梅吴光国汕头大学理学院化学系先进材料研究所汕头515063

以HTEMPO(2,2,6,6-四甲基-4-羟基哌啶-1-氧自由基)和TMPD(2,2,6,6-四甲基哌啶酮)为调控介质,以Irgacure 651为引发剂,研究了甲基丙烯酸甲酯(MMA)光聚合体系的控制反应动力学,比较了单分子(HTEMPO为调控介质)和双分子(HTEMPO和TMPD为调... 详细信息

以HTEMPO(2,2,6,6-四甲基-4-羟基哌啶-1-氧自由基)和TMPD(2,2,6,6-四甲基哌啶酮)为调控介质,以Irgacure 651为引发剂,研究了甲基丙烯酸甲酯(MMA)光聚合体系的控制反应动力学,比较了单分子(HTEMPO为调控介质)和双分子(HTEMPO和TMPD为调控介质)调控体系,并讨论了HTEMPO和HTEM-PO/TMPD在MMA光聚合体系中的调控作用、光敏化作用和原位光氧化反应.结果表明,对MMA光聚合体系,以HTEMPO/TMPD为控制介质的双分子调控体系是有效的,获得了良好的ln([M0]/[M])与时间,数均分子量与转化率之间的线性动力学关系,并且PMMA均聚物的多分散性指数(PD I)随着转化率的提高而减小.在高转化率(>85%)下,体系的多分散性指数(PD I)最小值可达到1.2.

关键词：可控/活性光聚合甲基丙烯酸甲酯氮氧自由基 2,2,6,6-四甲基-4-羟基哌啶-1-氧自由基 2,2,6,6-四甲基哌啶酮

Positron Emission Tomography Molecular Imaging for Phenotyping and Management of Lymphoma

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Phenomics 2022年第2期2卷 102-118页

作者： Xiaohui Zhang Han Jiang Shuang wu Jing Wang Rui Zhou Xuexin He Shufang Qian Shuilin Zhao Hong Zhang Ali Cahid Civelek mei Tian Department of Nuclear Medicine and PET Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009ZhejiangChina Key Laboratory of Medical Molecular Imaging of Zhejiang Province Hangzhou 310009ZhejiangChina Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University Hangzhou 310009ZhejiangChina PET-CT Center Fujian Medical University Union HospitalFuzhou 350001FujianChina Department of Medical Oncology The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009ZhejiangChina Key Laboratory for Biomedical Engineering of Ministry of Education Zhejiang UniversityHangzhou 310027ZhejiangChina College of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou 310027ZhejiangChina Department of Radiology and Radiological Science Johns Hopkins MedicineBaltimoreMD 21287USA Human Phenome Institute Fudan UniversityShanghai 201203China

Positron emission tomography(PET)represents molecular imaging for non-invasive phenotyping of physiological and biochemical processes in various oncological *** imaging with 18F-fluorodeoxyglucose(18F-FDG)for glucose metabolism evaluation is the standard imaging modality for the clinical management of *** of the 18F-FDG PET applications is the detection and pre-treatment staging of lymphoma,which is highly sensitive.18F-FDG PET is also applied during treatment to evaluate the individual chemo-sensitivity and accordingly guide the response-adapted *** the end of the therapy regiment,a negative PET scan is indicative of a good prognosis in patients with advanced Hodgkin’s lymphoma and diffuse large B-cell ***,adjuvant radiotherapy may be *** PET studies using non-18F-FDG radiotracers,such as 68Ga-labeled pentixafor(a cyclic pentapeptide that enables sensitive and high-contrast imaging of C-X-C motif chemokine receptor 4),68Ga-labeled fibroblast activation protein inhibitor(FAPI)that reflects the tumor microenvironment,and 89Zr-labeled atezolizumab that targets the programmed cell death-ligand 1(PD-L1),may complement 18F-FDG and offer essential tools to decode lymphoma phenotypes further and identify the mechanisms of lymphoma therapy.

关键词： Positron emission tomography(PET) Lymphoma Glucose metabolism Staging Response assessment