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Magnetotelluric sounding in western Tibet

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Chinese Science Bulletin 1997年第8期42卷 678-681页

作者： Ma, xb kong, XR Yu, S Institute of Geophysics Chinese Academy of Sciences Beijing China

THE magnetotelluric sounding(MT)profile from Gyirong to Sangehu in western Tibet indi-cates that the surveyed region is divided into four tectonic units by Yarlung Zangbo SutureZone(S.Z.),Bangongco-Nujiang *** Lugu **... 详细信息

关键词： magnetotelluric sounding conductivity structure of lithosphere high conductivity layer Tibet Gandise unit Qiangtang unit.

A land use regression model incorporating data on industrial point source pollution

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Journal of Environmental Sciences 2012年第7期24卷 1251-1258页

作者： Li Chen Yuming Wang Peiwu Li Yaqin Ji Shaofei kong Zhiyong Li Zhipeng Bai College of Urban and Environmental Science Tianjin normal UniversityTianjin 300387China College of Environmental Science and Engineering Nankai UniversityTianjin 300071China State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution and Control Tianjin 300071China Chinese Research Academy of Environmental Sciences Beijing 100012China

Advancing the understanding of the spatial aspects of air pollution in the city regional environment is an area where improved methods can be of great benefit to exposure assessment and policy support. We created land use regression （LUR） models for SO2, NO2 and PMI0 for Tianjin, China. Traffic volumes, road networks, land use data, population density, meteorological conditions, physical conditions and satellite-derived greenness, brightness and wetness were used for predicting SOa, NO2 and PMt0 concentrations. We incorporated data on industrial point sources to improve LUR model performance. In order to consider the impact of different sources, we calculated the PSIndex, LSIndex and area of different land use types （agricultural land, industrial land, commercial land, residential land, green space and water area） within different buffer radii （1 to 20 kin）. This method makes up for the lack of consideration of source impact based on the LUR model. Remote sensing-derived variables were significantly correlated with gaseous pollutant concentrations such as SO2 and NO2. R2 values of the multiple linear regression equations for SO2, NO2 and PM10 were 0.78, 0.89 and 0.84, respectively, and the RMSE values were 0.32, 0.18 and 0.21, respectively. Model predictions at validation monitoring sites went well with predictions generally within 15% of measured values. Compared to the relationship between dependent variables and simple variables （such as traffic variables or meteorological condition variables）, the relationship between dependent variables and integrated variables was more consistent with a linear relationship. Such integration has a discernable influence on both the overall model prediction and health effects assessment on the spatial distribution of air pollution in the city region.

关键词： land use regression air pollution Tianjin point source GIS

Development of small intestinal barrier function and underlying mechanism in Chinese indigenous and Duroc piglets during suckling and weaning periods

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Animal Nutrition 2024年第1期16卷 429-442页

作者： Sujuan Ding Yating Cheng Md Abul Kalam Azad Qian Zhu Pan Huang Xiangfeng kong CAS Key Laboratory of Agro-ecological Processes in Subtropical Region Hunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessInstitute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

This study explored the developmental changes in small intestinal barrier function and the potential regulatory roles of intestinal microbiota and metabolites in different breeds of piglets during suckling and weaning *** black(TB),Xiangcun black(xb),and Duroc(DR)piglets(10 litters per breed;half male and half female)were selected for sampling to evaluate the intestinal barrier-related indexes and intestinal microbiota and metabolites at 1,10,21(weaned),and 24(3 d after weaning)d *** results showed that weaning led to severe shedding of small intestinal microvilli and sparse microvilli arrangement.D-lactate level in the ileum of TB and xb piglets during suckling and weaning periods was lower(Pxb piglets than that of DR piglets,and it was the highest in the ileum of TB piglets at 21 d *** expression levels of mucin 2 and mucin 13 were higher(Pxb piglets than those of DR piglets at 21 d old,whereas mucin2 and mucin 13 in the ileum of TB and xb piglets were higher(Pxb piglets had a lower relative abundance of Escherichia_Shigella at 21 and 24 d old,but they had higher Streptococcus at 1 and 24 d old than DR piglets(Pxb piglets had higher intestinal permeability during the suckling period and a stronger intestinal mechanical barrier after ***,intestinal microbiota and metabolites are the key factors for developing small intestinal barrier functions in different breeds of piglets.

关键词： Chinese indigenous piglet Duroc piglet Immune function Intestinal barrier function Weaning stress

Mapping of quantitative trait loci for fiber and lignin contents from an interspecific cross Oryza sativa×Oryza rufipogon

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 518-526页

作者： Jian-kun XIE Xiang-li kong Jie CHEN Biao-lin HU Piao WEN Jie-yun ZHUANG Jin-song BAO Institute of Nuclear Agricultural Sciences College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China College of Life Sciences Jiangxi Normal University Nanchang 330022 China China National Rice Research Institute Hangzhou 310006 China

Rice straw is always regarded as a by-product of rice production,but it could be a significant energy source for ruminant *** of the genetic variation and genetic architecture of cell wall traits will facilitate rice breeders by improving relevant traits through selective breeding and genetic *** common wild rice,Oryza rufipogon Griff.,which is considered to be the progenitor of Oryza sativa,has been widely utilized for the identification of genes of agronomic importance for rice genetic *** the present study,the mapping of quantitative trait loci (QTLs) for acid detergent fiber (ADF),neutral detergent fiber (NDF),acid detergent lignin (ADL),and ADL/NDF ratio was carried out in two environments using a backcrossed inbred line (BIL) population derived from a cross between the recurrent parent Xieqingzao B (xb) and an accession of Dongxiang wild rice (DWR).The results indicated that all four traits tested were continuously distributed among the BILs,but many BILs showed transgressive segregation.A total of 16 QTLs were identified for the four traits,but no QTLs were in common in two environments,suggesting that environment has dramatic effects on fiber and lignin *** to the QTL positions for grain yield-related traits,there were no unfavorable correlations between grain yield components and cell wall traits in this *** QTLs identified in this study are useful for the development of dual-purpose rice varieties that are high in grain yield and are also high in straw quality.

关键词： Rice straw Acid detergent fiber Lignin Quantitative trait loci

基于Logistic方程描述的鱼食和阿特拉津共同作用对铜绿微囊藻生长的影响

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环境科学研究 2018年第10期31卷 1761-1770页

作者：黄岁樑孔文文南开大学环境科学与工程学院水环境数值模拟研究室天津300350 环境污染过程与基准教育部重点实验室天津300350 天津市城市生态环境修复与污染防治重点实验室天津300350

在养殖水域中地表径流等可引起水域中除草剂浓度升高,威胁养殖水环境的生态平衡.为评价阿特拉津和鱼食在水环境中的生态风险,以ρ(阿特拉津)(0、5、10、20和40μg/L)及鱼食(鱼食为MII培养基中的氮、磷营养源)投加量(0. 05、0. 20 g; d<0... 详细信息

在养殖水域中地表径流等可引起水域中除草剂浓度升高,威胁养殖水环境的生态平衡.为评价阿特拉津和鱼食在水环境中的生态风险,以ρ(阿特拉津)(0、5、10、20和40μg/L)及鱼食(鱼食为MII培养基中的氮、磷营养源)投加量(0. 05、0. 20 g; dxb'描述,R2分别为0. 72~0. 78、0. 66~0. 83和0. 55~0. 56.研究显示,Logistic方程可用于分析阿特拉津和鱼食对铜绿微囊藻生长的影响,且藻类生长与营养盐质量浓度之间存在一定的定量关系.

关键词：鱼食铜绿微囊藻阿特拉津氮磷

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用于生态修复工程的保水材料性能对比研究

铁道标准设计 2018年第10期62卷 192-195页

作者：孔德刚中铁科学研究院有限公司成都611731

保水材料的选用是决定干旱、半干旱地区人工植被建植效果的关键因素之一。通过对超吸水纤维(SAF)和保水剂(SAP)的保水性能开展各项测试,明确各产品的适用条件。结果表明:(1)在去离子水中,SAF和SAP的饱和吸水倍率分别约为150 g·g^(-1)和... 详细信息

保水材料的选用是决定干旱、半干旱地区人工植被建植效果的关键因素之一。通过对超吸水纤维(SAF)和保水剂(SAP)的保水性能开展各项测试,明确各产品的适用条件。结果表明:(1)在去离子水中,SAF和SAP的饱和吸水倍率分别约为150 g·g^(-1)和233 g·g^(-1),其达到饱和吸水倍率所需的时间分别为15~20 min和180 min;(2)SAF和SAP的吸水倍率都受pH和盐分影响较大,吸水率随p H值的增加呈倒"Λ"型变化趋势,在中性条件下效果最优;水体中电解质浓度越高,吸水倍率越差;(3)在室外条件下,SAF对土壤中入渗水的截留效果和保水性能均优于SAP;因此建议在边坡植被恢复等工程中应优先选用SAF作为保水材料。

关键词：超吸水纤维(SAF) 保水剂(SAP) 吸水倍率

利用光谱吸收深度定量反演碳酸盐矿物的影响因素及应用分析

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光谱学与光谱分析 2021年第7期41卷 2226-2232页

作者：翟文羽陈磊徐艺轩孔祥玉天津师范大学地理与环境科学学院天津300387

光谱吸收特征是矿物识别与定量反演的重要指标。为提高利用光谱吸收特征定量反演矿物精度,以方解石为代表,以线性混合光谱模型与连续统去除方法为基础,以连续统去除吸收深度(CRBD)为分析对象,按端元光谱在2.33μm附近有无吸收特征对光... 详细信息

光谱吸收特征是矿物识别与定量反演的重要指标。为提高利用光谱吸收特征定量反演矿物精度,以方解石为代表,以线性混合光谱模型与连续统去除方法为基础,以连续统去除吸收深度(CRBD)为分析对象,按端元光谱在2.33μm附近有无吸收特征对光谱进行分类,并分析每类数据与方解石混合光谱CRBD随丰度、反射率以及光谱特征等影响因素的变化规律,进而非线性拟合其变化范围并提出一种新的矿物含量表示方法。研究结果表明,端元丰度对CRBD值影响较大,方解石丰度越大,吸收特征越明显,CRBD值越大。同样,混合端元反射率与光谱特征对混合光谱CRBD值影响也较明显,当混合端元光谱在2.33μm附近为无特征时,端元光谱反射率越小,CRBD随碳酸盐丰度变化上凸越明显,为反射峰特征时,端元光谱反射率越大,下凹越明显;混合端元在2.33μm附近为吸收谷特征时,CRBD随碳酸盐丰度接近线性变化。通过交叉分析与多端元混合光谱CRBD变化分析发现,混合光谱CRBD随碳酸盐矿物丰度及混合端元反射率变化受限于一定范围,其上限拟合方程满足指数函数变化,下限拟合方程为三次多项式函数,且拟合精度较高,R 2均高于0.99,RMSE低于0.005。为实现矿物含量的精确预测,根据拟合方程提出一种以变化范围替代定量值来表示碳酸盐矿物丰度分布的方法,实现碳酸盐矿物含量反演的范围表示。通过影响因素分析及范围表示法可为矿产监测、定量评估等提供新的表达方法,为建立具有普适性的地物定量反演模型提供理论参考。

关键词：连续统去除吸收深度(CRBD) 碳酸盐定量反演影响因素