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中性黄220酸性浴锦纶染色匀染性研究
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作者 周大洲 余志成 宋凯利 《纺织科学与工程学报》 CAS 2024年第4期32-37,共6页
为了提升中性黄220染料的利用率,减小染色残液对环境的污染,采用酸性浴染色锦纶织物。首先选取不同pH值对锦纶织物进行染色,测试染色织物K/S值及匀染性,并分析染色不匀的产生原因,在此基础上,研究螯合分散剂对中性黄220染色K/S值及匀染... 为了提升中性黄220染料的利用率,减小染色残液对环境的污染,采用酸性浴染色锦纶织物。首先选取不同pH值对锦纶织物进行染色,测试染色织物K/S值及匀染性,并分析染色不匀的产生原因,在此基础上,研究螯合分散剂对中性黄220染色K/S值及匀染性的影响,优化染色工艺,研究螯合分散剂提升匀染性的作用机理。结果表明:在pH值为4的条件下,中性黄220能够具有更高的染色K/S值,但染色织物产生严重色花、色点,加入螯合分散剂后,滤纸表面沉淀及染料粒径明显减小,匀染性明显提升,最佳染色工艺:染色pH值为4,螯合分散剂X1用量4 g/L,升温速率为1℃/min,100℃保温60 min。 展开更多
关键词 螯合分散剂 中性黄220 染色 匀染性 锦纶织物
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悬浮态TiO_2光催化降解偶氮染料中性深黄GL 被引量:1
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作者 朱振中 任建荣 陈坚 《江南大学学报(自然科学版)》 CAS 2003年第2期179-182,共4页
采用紫外杀菌灯作为光源,以悬浮态TiO2为光降解催化剂进行了偶氮染料中性深黄GL的光催化降解研究.讨论了体系的pH值、催化剂的投入量、通气量以及起始浓度等因素对光催化降解中性深黄GL效率的影响.结果表明中性深黄GL的光催化降解适宜... 采用紫外杀菌灯作为光源,以悬浮态TiO2为光降解催化剂进行了偶氮染料中性深黄GL的光催化降解研究.讨论了体系的pH值、催化剂的投入量、通气量以及起始浓度等因素对光催化降解中性深黄GL效率的影响.结果表明中性深黄GL的光催化降解适宜条件为:pH=2.00;催化剂的投入量为1.4g/L;通气量为300mL/min.光降解100min,脱色率可达96%,降解后的染料已基本无色.动力学研究表明:中性深黄GL的光催化降解符合一级动力学规律.在λ=436nm处,中性深黄GL的光最大降解速率Kdmax=-1.3643mg/(L·min),催化降解的表观反应速率常数k=0.0268min-1. 展开更多
关键词 染料废水 废水处理 偶氮染料 中性GL 光催化降解 悬浮态TiO2 光降解催化剂 降解速率
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中性亮黄3GL合成研究
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作者 王英俊 刘茜 《皮革化工》 2002年第4期23-27,共5页
本文简要叙述由间二氨基苯磺酸、苯胺等为原料分别与三聚氯氰缩合 ,缩合物经重氮后与邻氯苯基吡唑酮偶合合成染料中性亮黄 3GL的工艺过程。
关键词 中性3GL 合成 研究 染料 间二氨基苯磺酸 苯胺 三聚氯氰
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稻草作为生物吸附剂去除水溶液中偶氮染料的研究 被引量:2
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作者 李伟胜 赵晖 +1 位作者 钟店 杨明 《江西化工》 2012年第1期92-94,共3页
用低值易得的稻草作为生物吸附剂对活性红和中性黄两种偶氮染料进行吸附处理研究,考察了吸附剂粒径、初始染料浓度、吸附时间、溶液初始pH等因素对染料吸附的影响。结果显示,吸附剂粒径200目、活性红染料浓度40mg/L、中性黄染料浓度50m... 用低值易得的稻草作为生物吸附剂对活性红和中性黄两种偶氮染料进行吸附处理研究,考察了吸附剂粒径、初始染料浓度、吸附时间、溶液初始pH等因素对染料吸附的影响。结果显示,吸附剂粒径200目、活性红染料浓度40mg/L、中性黄染料浓度50mg/L、吸附时间20min、吸附物剂量5g/L、初始pH2时,碎稻草对两种偶氮染料的吸附效果显著,分别达到活性红84%、中性黄94%。 展开更多
关键词 稻草 生物吸附剂 活性红 中性黄 废水
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Effects of Different Yellowing Conditions on Neutral Aroma Components and Smoking Quality of Flue-cured Upper Leaves
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作者 张真美 赵铭钦 +5 位作者 王一丁 梅雅楠 高净净 李燕 赵东杰 王鹏泽 《Agricultural Science & Technology》 CAS 2017年第3期424-431,共8页
A heated air circulation standard curing barn was used for baking tobacco leaves, and the effects of different yellowing conditions during the baking process on contents of neutral aroma components and smoking quality... A heated air circulation standard curing barn was used for baking tobacco leaves, and the effects of different yellowing conditions during the baking process on contents of neutral aroma components and smoking quality of upper leaves were studied by setting different yellowing time and color-fixing time. The results showed that during the baking process, only by prolonging the yellowing time by 24 h on the basis of control, the content of every kind of neutral aroma components in- creased obviously and the content of solanone increased by nearly 2.20 times. It was unfavorable for the degradation and accumulation of aroma components when only prolonging color-fixing time by 24 h. Prolonging both yellowing time and color- fixing time by 24 h mainly promoted the accumulation of chlorophyll degradation product neophytadiene, which increased by 33.24%, while the degradation and ac- cumulation of some aroma components were inhibited, indicating that only prolonging the yellowing time by 24 h could promote the accumulation of various kinds of neu- tral aroma components and improve the quality of tobacco leaves. The regression models were established of neutral aroma components in the first and second prin- cipal components to total aroma content, which were y=x+0.053 47 (R^2=0.919 7) and y=x+0.147 5 (R^2=0.698 4), respectively, and they were verified to be feasible. 展开更多
关键词 Flue-cured tobacco Yellowing conditions Neutral aroma components Smoking quality PCA and PLS
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维生素K止血的奥妙
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作者 王仲礼 《科技信息》 1997年第2期23-23,共1页
在维生素家族中,有一名止血“功臣”——维生素K。人体缺少它,出血就不能凝固,导致血流不止,危及生命。科学家经过潜心研究,逐步揭开了它的奥秘。 人们把从紫苜宿等植物体中提纯出来的维生素K命名为维生素K1,把从动物体中提取的维生素K... 在维生素家族中,有一名止血“功臣”——维生素K。人体缺少它,出血就不能凝固,导致血流不止,危及生命。科学家经过潜心研究,逐步揭开了它的奥秘。 人们把从紫苜宿等植物体中提纯出来的维生素K命名为维生素K1,把从动物体中提取的维生素K命名为维生素K2。它们的性格是异中有同,同中有异。相同的是它们都是中性黄色的化合物,不溶于水,只溶于油脂等有机溶剂,性质十分稳定,不怕酸,也不怕热。 展开更多
关键词 维生素K1 维生素K2 凝血酶元 有机溶剂 异中有同 可溶性纤维蛋白 中性黄 同中有异 植物体 营养状况
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Male mate choice in Tibetan macaques Macaca thibetana at Mt.Huangshan,China 被引量:3
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作者 Min ZHANG Jinhua LI +2 位作者 Yong ZHU Xi WANG Su WANG 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第2期213-221,共9页
Though females are generally more selective in mate choice, males may also benefit from mate choice if male reproductive success is limited by factors other than simply the number of female mates, and if females diffe... Though females are generally more selective in mate choice, males may also benefit from mate choice if male reproductive success is limited by factors other than simply the number of female mates, and if females differ in short-term reproductive potential. We studied male mate choice in a free-ranging troop of Tibetan macaques Macaca thibetana at Mt. Huangshan, China, from August 2007 to April 2008. We employed focal animal sampling and all occurrence sampling to record sexual related behaviors. Eight adult females were divided into three female quality categories according to the females' age, rank and parity. Using male mating effort as a proxy for male mate choice, we found that males do distinguish female quality and show time-variant mating strategies. Specifically, females with dominant rank, high fecundity, and middle age attracted significantly more males. Our results suggest that female short-term reproductive potential appears to be an important variable in determining male mating effort. Male Tibetan macaques do exercise mate choice for higher quality females as well as reduce useless reproductive cost, which is consistent with the direct benefits theory of mate choice. 展开更多
关键词 Tibetan macaques Macaca thibetana Direct benefits theory Male mate choice Reproductive potential Reproductive success
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Phytoplankton diversity in the East China Sea and Yellow Sea measured by PCR-DGGE and its relationships with environmental factors 被引量:7
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作者 孙静 于志刚 +6 位作者 高亚辉 周茜茜 甄毓 陈洪涛 赵丽媛 姚庆祯 米铁柱 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期315-322,共8页
Relationships between phytoplankton community composition and environmental variables in the East China Sea (ECS) and Yellow Sea (YS) were investigated using geochemical and molecular microbiology methods. The diversi... Relationships between phytoplankton community composition and environmental variables in the East China Sea (ECS) and Yellow Sea (YS) were investigated using geochemical and molecular microbiology methods. The diversity of phytoplankton was characterized using cultivation-independent PCR-based denaturing gradient gel electrophoresis (DGGE). Groups resulting from unweighted pair-group method with arithmetic averages clustering of the DGGE profiles showed good consistency with the eco-environmental characteristics of the sea area they belonged to. Additionally, the clustering results based on DGGE fingerprinting and those based on morphological compositions were practically identical. The relationship of phytoplankton diversity to environmental factors was statistically analyzed. Temperature, dissolved inorganic nitrogen (DIN), and silicate-Si were found significantly related to the phytoplankton community composition. Canonical correspondence analysis (CCA) was performed to reveal the relationship between community composition and these three environmental factors. Generally, values of the ECS are clearly separated from those of the YS in the CCA biplot, due to mainly the effect of temperature and DIN. 展开更多
关键词 canonical correspondence analysis (CCA) denaturing gradient gel electrophoresis (DGGE) PHYTOPLANKTON East China Sea Yellow Sea
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青云山风景区土壤调查初报 被引量:1
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作者 林道清 《林业勘察设计》 2003年第1期52-55,共4页
对青云山林业土壤进行全面调查,结果表明:山地土壤有2个土类、6个亚类、12个土属,土属分布以酸性岩红壤为主。占59%;中性岩黄红壤次之,占10.5%;酸性岩粗骨性红壤占9.0%,酸性岩暗红壤占7.4%,其余土属面积较小。并研究了主要土壤类型... 对青云山林业土壤进行全面调查,结果表明:山地土壤有2个土类、6个亚类、12个土属,土属分布以酸性岩红壤为主。占59%;中性岩黄红壤次之,占10.5%;酸性岩粗骨性红壤占9.0%,酸性岩暗红壤占7.4%,其余土属面积较小。并研究了主要土壤类型的理化性质,认为该区域土壤肥力较高。 展开更多
关键词 青云山风景区 土壤调查 林业土壤 酸性岩红壤 中性红壤 酸性岩粗骨性红壤 理化性质
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Study of dual-directional regulatory effect of Banxia (Pinellia ternata) and Huanglian (Coptis chinensis) drug pair on gastrointestinal movement of mice 被引量:1
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作者 Yue Ji Jun-Chen Li +5 位作者 Jing-Yan Meng Xue-Rou Yan Jian-Liang Li Qing-Yun Zhao Kang Yang Chun-Liu Liu 《Traditional Medicine Research》 2018年第3期148-156,共9页
Objective: To evaluate the regulatory effects of Banxia (Pinellia ternata, P) and Huanglian (Coptis chinensis, C) drugpair, derived from Banxiaxiexin soup, on the gastrointestinal movement of mice with functional... Objective: To evaluate the regulatory effects of Banxia (Pinellia ternata, P) and Huanglian (Coptis chinensis, C) drugpair, derived from Banxiaxiexin soup, on the gastrointestinal movement of mice with functional dyspepsia. Methods:Mice were treated with different proportions of the P and C drug pair (1:1, 3:1, and 4:1) for 10 days, and subsequentlyinjected with atropine (ATR) or neostigmine (NEO). The effects of the different proportions of P and C were evaluatedbased on the alvine advance rate. In addition, we used the same modeling method used in the first experiment andadministered P: C at ratio of 3:1 and at different doses respectively (4.68 g/L, 2.34 g/L, and 1.17 g/L), and tested levelsof the gastrointestinal hormones, gastrin (GAS), vasoactive intestinal polypeptide (VIP), and somatostatin (SS) in thesmall intestinal tissue using an enzyme-linked immunosorbent assay. Results: In the groups of NEO-induced mice, P:Cat ratios of 1:1, 3:1, and 4:1 significantly reduced the alvine advance rate compared with the NEO model group (P =0.003, P = 0.012 and P = 0.021, respectively). In the groups of ATR-induced mice, only P:1 at ratio of 3:1 significantlyincreased the alvine advance rate compared with the ATR model group (P = 0.007). After exposure to P: C at ratio of 3:1and at different dose, the GAS level was lower in the low-, medium-, and high-dose NEO groups than that in the NEOmodel group (P = 0.001, P = 0.004, and P = 0.003, respectively). The VIP levels were higher in the medium-andhigh-dose NEO groups than that in the NEO model group (P = 0.004 and P = 0.002, respectively). In addition, the SSlevel increased in the NEO medium-dose group compared with that in the NEO model group (P = 0.002). The GAS levelwas higher in the ATR medium- and high-dose groups than in the ATR model group (P = 0.007 and P = 0.021,respectively). The VIP level was lower in the ATR low-, medium-, and high-dose than that in the ATR model group (P =0.001, P = 0.001, and P = 0.001, respectively). Furthermore, the SS level was lower in the ATR medium- and high-dosegroups than that in the ATR model group (P = 0.001 and P = 0.006). Conclusion: The PC drug pair bidirectionallyadjusted the NEO- and ATR-induced functional dyspepsia in mice by modulating GAS, VIP, and SS levels in theintestine. 展开更多
关键词 Functional dyspepsia Traditional Chinese medicine Banxia (Pinellia ternate) Huanglian (Coptis chinensis)
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Retrieval of inherent optical properties of the Yellow Sea and East China Sea using a quasi-analytical algorithm 被引量:7
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作者 青松 唐军武 +1 位作者 崔廷伟 张杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第1期33-45,共13页
We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coef... We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coefficients of typical coastal waters. The average percentage difference (APD) is in a range of 13.9%-38.5% for the total absorption coefficient (13.9% at 440 nm), and differences in particle backscattering coefficient bbp(2) are less than 50% (in the case of the updated QAA). To obtain improved results, we modified the QAA by adjusting the empirical relationships. The modified algorithm is then applied to the field data to test its performance. The APDs were 44.7%-46.6% for bbp(λ) and 9.9%-32.8% (9.9% at 555 nm) for the total absorption coefficient. This indicates that the modified QAA derives better results. We also used the modified model to derive phytoplankton pigment absorption (aph) and detritus and CDOM absorption (aug) coefficients. The APDs for aph and a dg at 440 nm are 37.1% and 19.8%. In this paper, we discuss error sources using the measured dataset. More independent field data can improve this algorithm and derive better results. 展开更多
关键词 inherent optical properties Yellow Sea and the East China Sea quasi-analytical algorithm
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Seasonal Variations of Several Main Water Masses in the Southern Yellow Sea and East China Sea in 2011 被引量:7
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作者 QUAN Qi MAO Xinyan +3 位作者 YANG Xiaodan HU Yingying ZHANG Haiyan JIANG Wensheng 《Journal of Ocean University of China》 SCIE CAS 2013年第4期524-536,共13页
The seasonal variations of several main water masses in the southern Yellow Sea (SYS) and East China Sea (ECS) in 2011 were analyzed using the in-situ data collected on four cruises.There was something special in the ... The seasonal variations of several main water masses in the southern Yellow Sea (SYS) and East China Sea (ECS) in 2011 were analyzed using the in-situ data collected on four cruises.There was something special in the observations for the Yellow Sea Warm Current (YSWC) ,the Yellow Sea Cold Water Mass (YSCWM) and the Changjiang Diluted Water (CDW) during that year.The YSWC was confirmed to be a seasonal current and its source was closely associated with the Kuroshio onshore intrusion and the northerly wind.It was also found that the YSCWM in the summer of 2011 occupied a more extensive area in comparison with the climatologically-mean case due to the abnormally powerful wind prevailing in the winter of 2010 and decaying gradually thereafter.Resulting from the reduced Changjiang River discharge,the CDW spreading toward the Cheju Island in the summer of 2011 was weaker than the long-term mean and was confined to flow southward in the other seasons.The other water masses seemed normal without noticeable anomalies in 2011.The Yellow Sea Coastal Current (YSCC) water,driven by the northerly wind,flowed southeastward as a whole except for its northeastward surface layer in summer.The Taiwan Warm Current (TWC) was the strongest in summer and the weakest in winter in its northward movement.The Kuroshio water with an enhanced onshore intrusion in autumn was stable in hydrographic features apart from the seasonal variation of its surface layer. 展开更多
关键词 water masses seasonal variations southern Yellow Sea East China Sea
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The influence of plant root system architectural properties upon the stability of loess hillslopes,Northeast Qinghai,China 被引量:22
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作者 FU Jiang-tao HU Xia-song +5 位作者 BRIERLEY Gary QIAO Na YU Qin-qin LU Hai-jing LI Guo-rong ZHU Hai-li 《Journal of Mountain Science》 SCIE CSCD 2016年第5期785-801,共17页
To investigate the influence of root system architectural properties of three indigenous (cold- adapted) shrubs on the hillslope stability of loess deposits in the Xining Basin, northeast part of Qinghai-Tibet Plate... To investigate the influence of root system architectural properties of three indigenous (cold- adapted) shrubs on the hillslope stability of loess deposits in the Xining Basin, northeast part of Qinghai-Tibet Plateau (QTP), indoor direct shear tests have been conducted on the remolded rooted soil of three shrubs. Test results show that root system architectural indices (root area ratio (RAR), root length density (RLD) and root density (RD)) of the shrubs decline with depth and the relationship between RAR, RD and depth is exponential, while a power relationship describes the relationship between RLD and depth. The cohesion force of remolded rooted soil for the shrubs initially increases with depth, but it then demonstrates a slightly decreasing trend, which can be described with a power relationship. Power relationships also describe relationships between cohesion force and RAR, RLD and RD for the shrubs. As the growth period increases from lO to 17 months, the incremental increase in RAR is 48.32% ~ 21o.25% for Caragana korshinskii Kom and 0.56% ~ 166.85% for ZygophyUum xanthoxylon (Bunge) Maxim. This proportional increase is notably larger than that for RLD and RD. The increment in RAR is marginally greater for C. korshinskff than it is for Z. xanthoxylon. Correspondingly, the cohesion force incremental rates of remolded rooted soil for C. korshinskii and Z. xanthoxylon are 12.41% ~ 25.22% and 3.45% ~ 17.33% respectively. Meanwhile, as root content increases, the contribution by roots to cohesion force increases markedly until a threshold condition is reached. 展开更多
关键词 Cold region Semiarid region Soil reinforcement Hillslope stability Root system architectural indices Plateau
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A Clinical Study on Haunglian Fire-Purging Mixture In Treatment of 46 Cases of Primary Hypertension 被引量:1
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作者 李运伦 段树民 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2005年第1期29-33, ,共5页
In order to observe the therapeutic effects of Huanglian Fire-Purging Mixture (黄连清降合剂) on primary hypertension, 46 cases of primary hypertension in the treatment group were treated with Huanglian Fire-Purging Mi... In order to observe the therapeutic effects of Huanglian Fire-Purging Mixture (黄连清降合剂) on primary hypertension, 46 cases of primary hypertension in the treatment group were treated with Huanglian Fire-Purging Mixture to clear away heat from the liver, relieve mental stress, purge fire and remove toxin;and the other 26 cases of primary hypertension in the control group were treated with Niuhuang Bolus for Lowering Blood Pressure (牛黄降压丸). The effect in the treatment group was obviously superior to that in the control group (P<0.05). The Huanglian Fire-Purging Mixture shows noticeable effects 3-6 hours after medication. The mixture can improve the clinical symptoms, the left ventricular diastolic function and myocardial ischemia, correct dyslipoproteinemia and dysglycemia, and reduce blood viscosity. And it is safe and with no obvious adverse reactions. 展开更多
关键词 PHYTOTHERAPY ADULT Aged Drugs Chinese Herbal FEMALE Humans HYPERTENSION Male Middle Aged Single-Blind Method Treatment Outcome
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Uncertainty of Slope Length Derived from Digital Elevation Models of the Loess Plateau, China 被引量:7
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作者 ZHU Shi-jie TANG Guo-an +1 位作者 XIONG Li-yang ZHANG Gang 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1169-1181,共13页
Although many studies have investigated slope gradient uncertainty derived from Digital Elevation Models(DEMs), the research concerning slope length uncertainty is far from mature. This discrepancy affects the availab... Although many studies have investigated slope gradient uncertainty derived from Digital Elevation Models(DEMs), the research concerning slope length uncertainty is far from mature. This discrepancy affects the availability and accuracy of soil erosion as well as hydrological modeling. This study investigates the formation and distribution of existing errors and uncertainties in slope length derivation based on 5-m resolution DEMs of the Loess Plateau in the middle of China. The slope length accuracy in three different landform areas is examined to analyse algorithm effects. The experiments indicate that the accuracy of the flat test area is lower than that of the rougher areas. The value from the specific contributing area(SCA) method is greater than the cumulative slope length(CSL), and the differences between these two methods arise from the shape of the upslope area. The variation of mean slope length derived from various DEM resolutions and landforms. The slope length accuracy decreases with increasing grid size and terrain complexity at the six test sites. A regression model is built to express the relationship of mean slope length with DEM resolution less than 85 m and terrain complexity represented by gully density. The results support the understanding of the slope length accuracy, thereby aiding in the effective evaluation of the modeling effect of surface process. 展开更多
关键词 Slope length Uncertainty Digital Elevation Models(DEM) Loess terrain
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Response of Vegetation Cover to Climate Change and Influence of Dusty Weather in the Desertloess Transitional Zone of China
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作者 Yajun WANG 《Agricultural Science & Technology》 CAS 2013年第10期1526-1528,F0003,共4页
[Objective]This study aimed to analyze the relationships of the normalized difference vegetation index(NDVI)(1981-2006)in the desert-loess transitional zone of China with precipitation and temperature.[Method]The aver... [Objective]This study aimed to analyze the relationships of the normalized difference vegetation index(NDVI)(1981-2006)in the desert-loess transitional zone of China with precipitation and temperature.[Method]The average method and the correlation function were applied in this study.[Result]The results indicated that during the growing season NDVI was positively correlated with precipitation in the current month,last month and the month before last,especially the last month.NDVI mostly negatively correlated with temperature,especially the temperature in the last month,which shows that the higher temperature,the more adverse the conditions for vegetation growth.[Conclusion]NDVI from August to October clearly is one of the significant factors influencing dust storm weather in spring of the next year. 展开更多
关键词 Desert-loess transitional zone of China NDVI Climate change Dusty weather
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Mapping Soil Salinity Using a Similarity-based Prediction Approach:A Case Study in Huanghe River Delta,China 被引量:4
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作者 YANG Lin HUANG Chong +2 位作者 LIU Gaohuan LIU Jing ZHU A-Xing 《Chinese Geographical Science》 SCIE CSCD 2015年第3期283-294,共12页
Spatial distribution of soil salinity can be estimated based on its environmental factors because soil salinity is strongly affected and indicated by environmental factors. Different with other properties such as soil... Spatial distribution of soil salinity can be estimated based on its environmental factors because soil salinity is strongly affected and indicated by environmental factors. Different with other properties such as soil texture, soil salinity varies with short-term time. Thus, how to choose powerful environmental predictors is especially important for soil salinity. This paper presents a similarity-based prediction approach to map soil salinity and detects powerful environmental predictors for the Huanghe(Yellow) River Delta area in China. The similarity-based approach predicts the soil salinities of unsampled locations based on the environmental similarity between unsampled and sampled locations. A dataset of 92 points with salt data at depth of 30–40 cm was divided into two subsets for prediction and validation. Topographical parameters, soil textures, distances to irrigation channels and to the coastline, land surface temperature from Moderate Resolution Imaging Spectroradiometer(MODIS), Normalized Difference Vegetation Indices(NDVIs) and land surface reflectance data from Landsat Thematic Mapper(TM) imagery were generated. The similarity-based prediction approach was applied on several combinations of different environmental factors. Based on three evaluation indices including the correlation coefficient(CC) between observed and predicted values, the mean absolute error and the root mean squared error we found that elevation, distance to irrigation channels, soil texture, night land surface temperature, NDVI, and land surface reflectance Band 5 are the optimal combination for mapping soil salinity at the 30–40 cm depth in the study area(with a CC value of 0.69 and a root mean squared error value of 0.38). Our results indicated that the similarity-based prediction approach could be a vital alternative to other methods for mapping soil salinity, especially for area with limited observation data and could be used to monitor soil salinity distributions in the future. 展开更多
关键词 soil salinization similarity-based prediction approach digital soil mapping Huanghe (Yellow) River Delta environmental factor
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Onset of Xiashu loess deposition in southern China by 0.9 Ma and its implications for regional aridification 被引量:13
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作者 Xusheng LI Zhiyong HAN +6 位作者 Huayu LU Yingyong CHEN Yang LI Xiaokang YUAN Yuwen ZHOU Mengyao JIANG Cunjuan LV 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第3期256-269,共14页
The Xiashu loess is a typical Quaternary eolian deposit in southem China and represents an important terrestrial paleoclimate archive in this low-latitude monsoon region. However, the chronological framework of Xiashu... The Xiashu loess is a typical Quaternary eolian deposit in southem China and represents an important terrestrial paleoclimate archive in this low-latitude monsoon region. However, the chronological framework of Xiashu loess deposition has yet to be established. Determining the timing of the onset of Xiashu loess deposition will allow researchers to better understand late Quaternary aridification across the Asian continent, the evolution of the East Asian monsoon and regional environmental changes in subtropical regions. Therefore, in this study, a systematic chronological study of the Xiashu loess is conducted to answer this question. For the first time, magnetostratigraphic classification reveals that the Matuyama/Bnmhes (M/B) reversal is present in the Xiashu loess at two sites in Jiangsu Province, the Qingshan profile at Yizheng and the Dagang core in Zhenjiang. Based on the results of magnetostratigraphy and optically stimulated luminescence (OSL) dating, the age of the lower boundary of the Xiashu loess is estimated to be approximately 0.9 Ma. Consequently, this Xiashu loess deposit is the oldest reported to date and is comparable in age to the red soil deposit in Xuancheng, Anhui Province. The onset of Xiashu loess deposition by 0.9 Ma represents the further expansion of arid range in Asia in the late Quaternary in response to significant aridification and winter monsoon strengthening in this subtropical region. We suggest that these climate changes were primarily driven by global cooling and an increase in high-latitude ice volume in the Northern Hemisphere and that the initiation of Xiashu loess accumulation was a regional response of southern China to the 0.9 Ma global cooling event. 展开更多
关键词 Xiashu loess CHRONOLOGY Magnetic stratigraphy ARIDIFICATION East Asian monsoon
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Application of the SCS-CN Model to Runoff Estimation in a Small Watershed with High Spatial Heterogeneity 被引量:26
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作者 XIAO Bo WANG Qing-Hai +2 位作者 FAN Jun HAN Feng-Peng DAI Quan-Hou 《Pedosphere》 SCIE CAS CSCD 2011年第6期738-749,共12页
For reasons of simplicity, the most commonly used hydrological models are based on the Soil Conservation Service Curve Number (SCS-CN) model, which is probably a good choice for the estimation of runoff on the Loess... For reasons of simplicity, the most commonly used hydrological models are based on the Soil Conservation Service Curve Number (SCS-CN) model, which is probably a good choice for the estimation of runoff on the Loess Plateau of China; however, the high spatial heterogeneity, mainly caused by a fragmented landform and variations in soil type, may limit its applicability to this region. Therefore, applicability of the SCS-CN model to a small watershed, Liudaogou on the plateau, was evaluated and the most appropriate initial abstraction ratio (I~/S) value in the model was quantified by the inverse method. The results showed that the standard SCS-CN model was applicable to the estimation of runoff in the Liudaogou watershed and the model performance was acceptable according to the values of relative error and Nash-Sutcliffe efficiency. The most appropriate Ia/S value for the watershed was 0.22 because with this modified Ia/S value, the model performance was slightly improved. The model performance was not sensitive to the modification of the Ia/S value when one heavy rainfall event (50.1 mm) was not considered, which implied that the model, using a standard Ia/S value, can be recommended for the Liudaogou watershed because single rainfall events exceeding 50 mm seldom occurred in that region. The runoff amount predicted for the Liudaogou watershed by the SCS-CN model, using the modified Ia/S value, increased gradually with increasing rainfall when rainfall values were lower than 50 mm, whereas the predicted amount increased rapidly when the rainfall exceeded 50 mm. These findings may be helpful in solving the problem of serious soil and water loss on the Loess Plateau of China. 展开更多
关键词 curve number initial abstraction ratio model performance RAINFALL soil and water loss
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Effect of Astragali and Angelica particle on proteinuria in Chinese patients with primary glomerulonephritis 被引量:7
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作者 Shen Peicheng Yang Xuejun He Liqun 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2016年第3期299-306,共8页
OBJECTIVE: To investigate the effect of the traditional Chinese herbs Astragali and Angelicae Sinensis(A & As) particle [contains Huangqi(Radix Astragali Mongolica), Danggui(Radix Angelicae Sinensis),Huzhanggeng(R... OBJECTIVE: To investigate the effect of the traditional Chinese herbs Astragali and Angelicae Sinensis(A & As) particle [contains Huangqi(Radix Astragali Mongolica), Danggui(Radix Angelicae Sinensis),Huzhanggeng(Rhizoma Polygoni Cuspidati) and Danshen(Radix Salviae Miltiorrhizae)] on proteinuria in glomerulonephritis patients with stage 2 chronic kidney disease.METHODS: A prospective, multi-center, and randomized controlled clinical trial was performed for 24 weeks. From March 2011 to April 2012, 158 patients from nine hospitals in China participated.They were randomized into the A&As group(79 cases, A&As particle 15.2 g/day) and losartan group(79 cases, losartan 50 mg/day). At each follow-up visit, clinical data including blood pressure, urinalysis, 24-h-urinary protein excretion, serum albumin and serum creatinine were collected.RESULTS: All 158 patients completed the follow-up. Proteinuria in the losartan group exhibited a biphasic time-dependent decline with a significant steady reduction from baseline to week 12(P = 0.0014), and a platform level during the remaining 12-week follow-up(P > 0.05). In contrast, there was a continual significant decrease of proteinuria in the A & As group(P < 0.001). When compared with the losartan results, proteinuria in the A & As group from week 16 to week 24 was significantly reduced(P < 0.001). Stable e GFRs and blood pressure were also observed in both groups. Medication side effects were minimal and non-fatal.CONCLUSION: For Chinese glomerulonephritis patients with stage 2 chronic kidney disease, therapy with A & As particles may provide effective anti-proteinuria treatment. 展开更多
关键词 Angelica sinensis Renal insufficiency CHRONIC GLOMERULONEPHRITIS PROTEINURIA MEDICINE Chinese Traditional
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