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Acta Geochimica 2006年第S1期 65-66页

作者： Mingyi wang, Xiaobing LIANG, Yaping ZHENG, Youzhi ZHAO, Zhongqing WEI State Key Laboratory of Environmental geochemistry, Institute of geochemistry,{3., guiyang 550002, China

The potential effect of variations in climate and agricultural practice on N_2O emissions (Ⅱ)——Variations in agricultural practice

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chinese Science Bulletin 1999年第S2期44卷 97-99页

作者： XU Wenbin~(1,2), HONG Yetang~1, CHEN Xuhui~3. LI Changsheng~4, LIN Qinghua~1 and wang Yu~1, 1. State Key Laboratory of Environmental geochemistry, Institute of geochemistry,{3., guiyang 550002, China 2. Institute of Environment and Resources Chemistry, Zhejiang University, Hangzhou 3.0027, China 3. Soil and Fertilizer Institute, Guizhou academy of Agricultural sciences, guiyang 550013. China 4. Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, USA State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Institute of Environment and Resources Chemistry Zhejiang University Hangzhou 310027 China Soil and Fertilizer Institute Guizhou Academy of Agricultural Sciences Guiyang 550013 China Institute for the Study of Earth Oceans and Space University of New Hampshire Durham NH United States

WE expanded Decomposition-Denitrification （DNDC）modeling study to systematically assess the potential effect of farming practice on N2O emission by choosing a corn-rape rotation and a soybean-winterwheat rotation field in Guizhou Province, westsouthern China, asN2O emission from subtropical agricultural soil study plots. These sensitivity studies address questions relevant to issue of how change in fanning practice might be used to mitigate emissions. Manure additions had the most pronounced impact on N2O emissions of farming practice simulatedand the influence of manure addition was nonlinear （fig. 1）. This result is consistent with previous studies for an Iowa corn field. The addition of manure remarkably elevates the level of organic carbon, enhances soil nitrogen mineralization, and increases the efficiency of N2O production. Simulated results alsoshowed that the influence of manure additions on N2O emission from soybean-winter wheat field had

关键词： N2O emission farming practice potential effect agricultural soil.

Total gaseous mercury emissions from mercury-enriched soil in Guizhou, China

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Acta Geochimica 2006年第S1期 243-244页

作者： Xinbin FENG, Shaofeng wang, Guangle QIU, Yamin HOU, Shunlin TANG State Key Laboratory of Environmental geochemistry, Institute of geochemistry,{3., guiyang 550002, China

The seasonal and daily CO_2 concentration variance in karst meadow soil profile with depth in Central Guizhou, China

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chinese Science Bulletin 1999年第S2期44卷 93-94页

作者： ZHENG Leping~(1,2), LI Tingyu~2, WAN Guojiang~2, wang Shijie~2 and OUYANG Ziyuan~2 1. Department of Environmental Science and Engineering, Shanghai University, Shanghai 200072, China 2. State Key Laboratory of Environmental geochemistry, Institute of geochemistry,{3., guiyang 550002, China Department of Environmental Science and Engineering Shanghai University Shanghai 200072 China State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE seasonal variance of soil CO2 concentration with depth in soil profile was widely studied. Few similarresearches on this topic have been done in karst area which comprises 15% global terrestrial area. In thisnote, the research results about the seasonal and daily soil CO2 concentration variance in karst area arereported. The soil gases were collected respectively by the sampling device at 200, 5,0, -5, -10,-15, -25, -3. and -45 cm from the land surface in meadow soil profile described by Zheng andlocated in the Hongfeng lake area in the central Guizhou Plateau which lies in the central East-Asia karstarea. Sampling time is in the morning, midday and at night in April, August and November, 1998 aswell as in January, 1999, respectively. Concentrations （volume percent） of CO2 in soil gas samples

关键词： soil CO2 concentration karst area Guizhou Province.

A new theoretical method to estimate the equilibrium distribution of clumped isotopes in nature

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A new theoretical method to estimate the equilibrium distrib...

中国矿物岩石地球化学学会第13.学术年会

作者： CAO Xiao-bin,LIU Yun State Key Laboratory of Ore Deposit geochemistry,Institute of geochemistry,chinese {3. of sciences,guiyang 550002, China

Stable isotope geochemistry,for a long time,has focused on the bulk isotope composition,which is characterized by one rare isotope’s concentration(e.g.,δO orδS).Multiply substituted isotopologues containing two or more rare isotopes(so-called clumps),however,has not been paid much attention until the work of Eiler and his colleagues(*** and Schauble,2004;wang et al.,2004;Ghosh et al.,2006;Schauble et al., 2006;Came et al.,2007;Eiler,2007;Guo et al.2009;Eagle et al.,2010).wang et al.(2004) firstly proposed a theoretical framework for clumped-isotope ***,they proposed a new concept"△",as the abundance of clumped isotope in excess of those expected for a stochastic distribution of isotopes,and determined

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影像学预测缺血性脑卒中复发的研究进展

磁共振成像 2024年第5期15卷 198-203页

作者：白帆王效春山西医科大学医学影像学院太原030001 山西医科大学第一医院影像科太原030001

缺血性脑卒中(cerebral ischemic stroke,CIS)具有发病率高、致残率高、致死率高和复发率高等特点,复发患者具有更高的致残率和死亡率。因此,尽早确定缺血性脑卒中复发高风险人群、筛查复发相关危险因素,并进行有针对性的干预,可有效降... 详细信息

缺血性脑卒中(cerebral ischemic stroke,CIS)具有发病率高、致残率高、致死率高和复发率高等特点,复发患者具有更高的致残率和死亡率。因此,尽早确定缺血性脑卒中复发高风险人群、筛查复发相关危险因素,并进行有针对性的干预,可有效降低复发风险、延缓复发进展。本文就影像学预测CIS复发的研究进展进行综述,以期加强对复发性CIS的认识,减少复发引起的相关不良事件的发生。

关键词：缺血性脑卒中复发影像学影像组学机器学习磁共振成像

大小龄红松木质部解剖特征的年龄效应及其对气候变化的响应差异

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生态学报 2024年第11期44卷 4876-4888页

作者：张琦苑丹阳王晓春东北林业大学生态研究中心森林生态系统可持续经营教育部重点实验室哈尔滨150040

树龄是影响树木生长的最重要因素之一。在气候变暖背景下,利用树干木质部解剖特征,分析不同树龄生长-气候关系,对准确评估树木对气候变化的响应和适应策略、预测气候变化下的森林动态至关重要。利用木材解剖学方法,比较了小兴安岭溪水... 详细信息

树龄是影响树木生长的最重要因素之一。在气候变暖背景下,利用树干木质部解剖特征,分析不同树龄生长-气候关系,对准确评估树木对气候变化的响应和适应策略、预测气候变化下的森林动态至关重要。利用木材解剖学方法,比较了小兴安岭溪水地区针阔混交林内大、小龄红松(Pinus koraiensis)木质部解剖特征及其对气候变化的响应异同。结果表明:大龄红松主要管胞特征值随年龄增加而呈上升趋势,但小龄红松的变化趋势并不明显,两者均在1840—1890年和1980—2010年间出现剧烈的波动。大、小年龄红松部分管胞特征与气候因子的关系具有一致性,管胞数量和理论导水率分别与月最高温度负相关和正相关;总管胞面积(负相关)、理论导水率(正相关)、平均水力直径(正相关)与月最低温度的关系一致;理论导水率与月总降水正相关;管胞占比、平均管胞面积、理论导水率、平均水力直径均与平均相对湿度正相关,且大龄红松相关性更强。大、小年龄红松管胞特征与气候因子的关系的不一致表现在,大龄红松管胞占比、平均管胞面积、总管胞面积和平均水力直径与月最高温度正相关,而这些关系在小龄红松则表现为负相关。大龄红松管胞数量与7—9月最低温度正相关,而在小龄红松表现为显著负相关;大、小龄红松除理论导水率外其他管胞特征与降水关系基本相反,其中管胞数量的相关性更强;大龄红松与7月、9月、年总降水量显著正相关,而小龄红松与6月和年总降水显著负相关;与月平均相对湿度的相关关系大龄红松表现为正相关或不显著,而小龄红松呈负相关关系。温度是限制大、小龄红松管胞特征生长的主要气候因子,降水的影响相对较弱,平均相对湿度对大小龄红松的影响差异不大。近几十年,小兴安岭地区气候暖干化趋势逐渐增强,这种暖干化会造成大、小龄红松生长的响应差异。若气候持续变暖或加剧,小龄红松会出现严重生长衰退。

关键词：红松管胞理论导水率早材气候变化木质部

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磁共振多模态功能成像在膀胱癌分期及分级中的应用研究进展

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磁共振成像 2024年第2期15卷 229-234页

作者：郭俊婷王效春山西医科大学医学影像学院太原030001 山西医科大学第一医院影像科太原030001

膀胱癌(bladder cancer,BC)是一种复发率高且易于进展的肿瘤,其治疗负担在所有癌症中位居第一,严重危害国民健康。精确的分期及分级对于BC诊疗决策有着重要的意义。近年来,随着膀胱成像与报告系统和MRI技术的飞速发展,扩散加权成像、动... 详细信息

膀胱癌(bladder cancer,BC)是一种复发率高且易于进展的肿瘤,其治疗负担在所有癌症中位居第一,严重危害国民健康。精确的分期及分级对于BC诊疗决策有着重要的意义。近年来,随着膀胱成像与报告系统和MRI技术的飞速发展,扩散加权成像、动态对比增强MRI、扩散峰度成像、体素内不相干运动、分数阶微积分扩散模型、合成磁共振技术和化学交换饱和转移成像等功能MRI技术可以无创地从扩散、血供、组织定量及代谢等多个方面评估肿瘤性质,以期术前评估肿瘤生物学特性、预测肿瘤复发进而帮助临床医生早期诊断、制订最优手术方式,提高患者生存质量,减少不必要的经济负担。上述技术逐渐成为研究热点,故本文就近年来国内外多模态功能MRI在BC分期及分级中的应用予以综述,为临床诊疗提供更加可靠的影像学依据。

关键词：膀胱癌磁共振成像多模态扩散加权成像分期分级

MAGNETOSTRATIGRAPHY OF PERMO-TRIASSIC BOUNDARY SECTION OF MEISHAN OF CHANGXING,ZHEJIANG

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Science China Chemistry 1989年第11期32卷 1401-1408页

作者：李华梅王俊达 guiyang Institute of geochemistry Academia Sinica. Guiyang 550002 PRC

A hundred and eleven samples were collected from the Permian-Triassic boundarysection of Meishan (3..1°N, 119.7°E) which includes the Changxing Formation of thelate Permian and the Qinglong Formation of early Triassic. The thickness of the sectionis about 60 m. Paleomagnetic results indicate that six normal and reversed polarity zoneswere recorded in the section which all belong to the Illawarra mixed interval. Theboundary of Permo-Triassic lies at 1.2 m (or 2.7 m) above the bottom of normal polarityzone V. The magnetic minerals in the rocks of the lower part of the Changxing Forma-tion mainly are goethite, haematite and titaniferous magnetite while in the upper part ofthe formation are chiefly titanomagnetite and magnetite, goethite is secondary. Magne-tite and haematite as the main magnetic minerals were included in marl and mudstone ofthe Qinglong Formation. Based on the results of the magnetically stable samples thepaleopole position of 50.7°N, 23..3.E was obtained, meanwhile, the paleolatitude ofthe sampling location is 12.3.N during the early Triassic.

关键词： Changxing Permo-Triassic magnetostratigraphy

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磁共振弹性成像在腹盆部肿瘤中的研究进展

磁共振成像 2024年第5期15卷 216-221页

作者：张潇月王效春山西医科大学医学影像学院太原030001 山西医科大学第一医院影像科太原030001

肿瘤力学特性与肿瘤侵袭、进展密切相关,准确评估肿瘤组织硬度对于肿瘤的检测、鉴别诊断、诊疗规划及预后评估具有重要意义。磁共振弹性成像(magnetic resonance elastography,MRE)能量化组织力学特性,无创定量评估组织硬度,进而间接反... 详细信息

肿瘤力学特性与肿瘤侵袭、进展密切相关,准确评估肿瘤组织硬度对于肿瘤的检测、鉴别诊断、诊疗规划及预后评估具有重要意义。磁共振弹性成像(magnetic resonance elastography,MRE)能量化组织力学特性,无创定量评估组织硬度,进而间接反映组织纤维化程度。本文将对MRE的基本原理、技术发展及其在腹盆部肿瘤中应用的研究现状进行综述,旨在为未来的研究提供新思路,推进MRE的不断成熟,辅助指导临床精准诊疗。

关键词：肝脏胰腺前列腺肾脏肿瘤磁共振弹性成像