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诃子的研究进展及质量标志物的预测 被引量:71
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作者 赵鹿 廖翠萍 +3 位作者 杨秀娟 董世奇 樊慧蓉 刘昌孝 《中草药》 CAS CSCD 北大核心 2020年第10期2732-2744,共13页
诃子是我国传统中药材,在云南、广东、广西、西藏等地均有分布,诃子在我国中医临床用药广泛,在蒙药、藏药中占有非常重要的地位。诃子化学成分丰富多样,主要包括酚酸类、鞣质类、三萜类、脂肪族类、黄酮类、挥发油、氨基酸类、微量元素... 诃子是我国传统中药材,在云南、广东、广西、西藏等地均有分布,诃子在我国中医临床用药广泛,在蒙药、藏药中占有非常重要的地位。诃子化学成分丰富多样,主要包括酚酸类、鞣质类、三萜类、脂肪族类、黄酮类、挥发油、氨基酸类、微量元素、碳水化合物等。现代药理学研究表明,诃子提取物具有抗氧化、抗癌抗肿瘤、解毒、抗菌、强心、抗炎、免疫调节、抗微生物、促进支气管平滑肌收缩等多种药理活性。通过查阅文献,从本草考证、化学成分、药理作用等方面对诃子研究进展进行阐述,根据质量标志物的核心理念,从植物亲缘学及化学成分特有性、传统功效、药性、药动学、新临床用途和化学成分可测性等方面对诃子质量标志物预测分析,为诃子质量评价研究提供参考。 展开更多
关键词 诃子 质量控制 质量标志物 酚酸 鞣质 三萜 抗氧化 抗肿瘤 解毒
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基于CiteSpace对山豆根研究进展的可视化分析 被引量:24
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作者 杨京航 康世奇 +2 位作者 苏晓慧 林娜 孔祥英 《中国中药杂志》 CAS CSCD 北大核心 2021年第7期1763-1768,共6页
运用CiteSpace 5.6.R5软件通过对中国知网(CNKI)数据库检索平台收录的1990—2020年山豆根相关研究的中文文献进行文献计量学分析,从论文的发文量、合作作者、合作机构、关键词的突现、共现、聚类进行分析及可视化展现。研究共纳入808篇... 运用CiteSpace 5.6.R5软件通过对中国知网(CNKI)数据库检索平台收录的1990—2020年山豆根相关研究的中文文献进行文献计量学分析,从论文的发文量、合作作者、合作机构、关键词的突现、共现、聚类进行分析及可视化展现。研究共纳入808篇中文文献,其中发文量最多的作者孙蓉,共计17篇,并形成以孙蓉为中心的研究团队;发文机构合作显示上海中医药大学药物安全评价研究中心是发文量最多的机构,共计29篇,还形成以山东省中医药研究院为核心的科研合作机构,并形成较为紧密的合作网络关系;文献关键词分析显示研究方向集中在山豆根的中医用药、药理机制、毒副反应、有效成分等,其中山豆根有效成分的药效与毒性研究成为热点趋势。 展开更多
关键词 山豆根 文献计量学 药用价值 可视化分析
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中国193个城市规划区土壤微量元素污染与健康风险 被引量:22
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作者 李括 彭敏 +9 位作者 杨峥 杨柯 刘飞 赵传冬 成晓梦 马宏宏 郭飞 唐世琪 刘应汉 成杭新 《环境科学》 EI CAS CSCD 北大核心 2020年第4期1825-1837,共13页
随着城市化进程的加快,城市表层土壤微量元素含量发生了不同程度的变化,城市土壤污染所引发的环境问题进一步凸显.为了系统研究我国31个省(自治区、直辖市)193个地级以上城市规划区表层土壤13种微量元素的含量特征、污染水平和暴露风险... 随着城市化进程的加快,城市表层土壤微量元素含量发生了不同程度的变化,城市土壤污染所引发的环境问题进一步凸显.为了系统研究我国31个省(自治区、直辖市)193个地级以上城市规划区表层土壤13种微量元素的含量特征、污染水平和暴露风险,利用地累积指数(Igeo)和综合污染指数(IPI)对土壤微量元素的污染水平进行了评价,采用美国环保署(USEPA)推荐的健康风险评估方法量化了居民暴露于城市土壤的健康风险.研究结果显示:城市规划区表层土壤As、Be、Cd、Co、Cr、Cu、Hg、Ni、Pb、Se、Tl、V和Zn等13个元素含量中位值分别是9.25、2.14、0.174、12.4、68.4、28.2、0.095、27.7、31.1、0.29、0.61、82.7和82.2 mg·kg^-1,相比于城市土壤背景值,Cd、Hg和Se是含量变化比较显著的元素.Igeo值表明城市规划区表层土壤污染最严重的是Hg,其次是Se和Cd,污染程度介于无污染至中度污染之间,其他元素无污染.综合污染指数IPIN显示:全国有22个城市规划区土壤已达到重度污染,16个城市达到中度污染,湖南省株洲市是全国土壤污染最严重的城市.健康风险评估结果表明:郴州市、黄石市、株洲市、湘潭市和龙岩市等5个城市规划区土壤暴露对未成年人具有潜在非致癌风险,其中土壤Pb摄入是引发风险的主要因素.建议在综合污染已达中度到重度污染的城市开展详查,摸清土壤污染状况及污染地块分布,建立污染地块清单和优先管控名录,实施污染调控和修复治理. 展开更多
关键词 微量元素 城市土壤 污染水平 健康风险 中国
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四川盆地常规天然气地质条件、资源潜力及勘探方向 被引量:16
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作者 朱华 杨光 +5 位作者 苑保国 应丹琳 戴鑫 周红飞 徐世琦 谈健康 《天然气地球科学》 EI CAS CSCD 北大核心 2018年第10期1475-1485,共11页
四川盆地纵向上从震旦系—侏罗系共发现了包括常规天然气、致密气、页岩气、致密油4种类型的工业油气流,其中常规气主要发育于中三叠统雷口坡组及其以下的海相碳酸盐岩地层中,为了预测四川盆地常规天然气未来勘探方向,在系统总结四川盆... 四川盆地纵向上从震旦系—侏罗系共发现了包括常规天然气、致密气、页岩气、致密油4种类型的工业油气流,其中常规气主要发育于中三叠统雷口坡组及其以下的海相碳酸盐岩地层中,为了预测四川盆地常规天然气未来勘探方向,在系统总结四川盆地常规天然气地质条件、成藏富集规律的基础上,评价盆地常规天然气资源潜力,明确剩余资源空间分布。结果表明:(1)四川盆地具有构造分区明显、4套广覆式烃源层、多套大面积孔隙型储层发育的常规天然气地质条件;(2)常规天然气富集主要受优质烃源岩、台缘和台内高能滩相、古构造和成藏组合等因素的控制,具有大气田近源分布、相带控储、古侵蚀面改善储渗条件、继承性古隆起控制油气富集和运移、优越的成藏组合有利于形成大中型气藏等特点;(3)基于盆地常规天然气地质条件,立足于"层",运用成因法、统计法及特尔菲综合法,预测四川盆地常规天然气地质资源量为12.5×10^(12)m^3。结合剩余资源空间分布特征,指出了四川盆地未来的总体勘探方向是:层系上主攻灯影组、龙王庙组及中二叠统勘探领域;区块上发展川中、川东地区,挖潜川南地区,开拓川西、川北地区。 展开更多
关键词 四川盆地 常规天然气 地质条件 富集规律 资源潜力 剩余资源分布 勘探方向
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川渝地区雾霾时空分布特征及影响因子分析 被引量:14
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作者 白莹莹 张德军 +2 位作者 杨世琦 王永前 刘川 《西南师范大学学报(自然科学版)》 CAS 北大核心 2018年第11期112-119,共8页
利用1981-2014年川渝地面气象观测资料,分析了川渝地区雾霾的时空分布特征及影响因子,结果表明:川渝地区雾日变化总体呈下降趋势,两种雾日观测资料的倾向率分别为-6d/10a和-8.2d/10a,研究时段内未出现突变点,80年代到90年代初,雾日变化... 利用1981-2014年川渝地面气象观测资料,分析了川渝地区雾霾的时空分布特征及影响因子,结果表明:川渝地区雾日变化总体呈下降趋势,两种雾日观测资料的倾向率分别为-6d/10a和-8.2d/10a,研究时段内未出现突变点,80年代到90年代初,雾日变化周期以2~4a为主,21世纪后以8~10a为主.霾日总体趋势与雾日变化相反,呈上升趋势,倾向率为8.2d/10a,1997年开始发生突变,90年代变化周期以2~4a为主,2000年后4~10a周期变化较显著.在对雾霾与风速和空气相对湿度的关系讨论中发现,整个川渝地区雾与风速的变化趋势一致,与相对湿度呈正相关;霾与风速的变化趋势相反,与相对湿度呈负相关. 展开更多
关键词 时空分布 影响因子
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土石混合体-基岩界面剪切力学特性试验研究 被引量:14
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作者 杨忠平 蒋源文 +2 位作者 李诗琪 李进 胡元鑫 《岩土工程学报》 EI CAS CSCD 北大核心 2020年第10期1947-1954,共8页
填方体–下伏基岩接触面间的剪切强度是控制高填方体或堆积体边坡稳定性的重要因素,界面强度参数取值是高填方工程设计的重要参数之一。通过较系统地室内大型直剪试验探讨了接触面粗糙度对土石混合料–基岩接触面剪切力学特性的影响。... 填方体–下伏基岩接触面间的剪切强度是控制高填方体或堆积体边坡稳定性的重要因素,界面强度参数取值是高填方工程设计的重要参数之一。通过较系统地室内大型直剪试验探讨了接触面粗糙度对土石混合料–基岩接触面剪切力学特性的影响。结果表明:在低法向应力作用下,剪应力–剪切位移曲线前期呈现出应变硬化现象,后期呈现出塑性应变现象,且接触面粗糙度越大接触面发生剪切破坏时变形越小;在高法向应力作用下,曲线呈现出应变硬化现象,无明显峰值;相同法向应力水平作用下,接触面粗糙度越大,土石混合体–基岩接触面剪切刚度越大。剪切界面上块石的破碎形态可分为完全破碎、部分破碎和表面磨损3种,随着接触面粗糙度的增加,剪切界面上块石的破碎总数也增加。接触面的抗剪强度、内摩擦角和表观黏聚力随着接触面粗糙度的增加而增大,相比于内摩擦角,接触面的表观黏聚力增大较为明显。接触面粗糙度对剪切带宽度有影响作用,表现为接触面粗糙度越大,剪切带越宽。 展开更多
关键词 土石混合体 基岩界面 粗糙度 剪切特性 块石破碎
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AIWW:a new nutrition-screening tool for the oncologic population 被引量:8
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作者 Yi-Zhong Ge Zhen-Ming Fu +37 位作者 qi Zhang Meng-Meng Song Guo-Tian Ruan Xi Zhang Xiao-Wei Zhang Xiang-Rui Li Kang-Ping Zhang Meng Tang Xiao-Yue Liu Ming yang Tong Liu Hai-Lun Xie He-yang Zhang Zi-Wen Wang Chun-Lei Hu shi-qi Lin Rui Zhang Hong-Xia Xu Wei Li Chun-Hua Song Ming Liu Jun-qiang Chen Kun-Hua Wang Li Bo Ming-Hua Cong Zeng-Ning Li Zeng-qin Guo Xiao-Bin Wang Bin-Yan Wang Benjamin Xu Xian-Hui qin Xi-Ping Xu Rocco Barazzoni qing-Hua Yao Min Weng Xian Shen Han-Ping shi The Investigation on Nutrition Status and Clinical Outcome of Common Cancers(INSCOC)Group 《Science China(Life Sciences)》 SCIE CAS CSCD 2023年第8期1831-1840,共10页
Malnutrition is a common comorbidity among patients with cancer.However,no nutrition-screening tool has been recognized in this population.A quick and easy screening tool for nutrition with high sensitivity and easy-t... Malnutrition is a common comorbidity among patients with cancer.However,no nutrition-screening tool has been recognized in this population.A quick and easy screening tool for nutrition with high sensitivity and easy-to-use is needed.Based on the previous 25 nutrition-screening tools,the Delphi method was made by the members of the Chinese Society of Nutritional Oncology to choose the most useful item from each category.According to these results,we built a nutrition-screening tool named age,intake,weight,and walking(AIWW).Malnutrition was defined based on the scored patient-generated subjective global assessment(PG-SGA).Concurrent validity was evaluated using the Kendall tau coefficient and kappa consistency between the malnutrition risks of AIWW,nutritional risk screening 2002(NRS-2002),and malnutrition screening tool(MST).Clinical benefit was calculated by the decision curve analysis(DCA),integrated discrimination improvement(IDI),and continuous net reclassification improvement(c NRI).A total of 11,360 patients(male,n=6,024(53.0%)were included in the final study cohort,and 6,363 patients had malnutrition based on PG-SGA.Based on AIWW,NRS-2002,and MST,7,545,3,469,and1,840 patients were at risk of malnutrition,respectively.The sensitivities of AIWW,NRS-2002,and MST risks were 0.910,0.531,and 0.285,and the specificities were 0.768,0.946,and 0.975.The Kendall tau coefficients of AIWW,NRS-2002,and MST risks were 0.588,0.501,and 0.326,respectively.The area under the curve of AIWW,NRS-2002,and MST risks were0.785,0.739,and 0.630,respectively.The IDI,c NRI,and DCA showed that AIWW is non-inferior to NRS-2002(IDI:0.002(-0.009,0.013),c NRI:-0.015(-0.049,0.020)).AIWW scores can also predict the survival of patients with cancer.The missed diagnosis rates of AIWW,NRS-2002,and MST were 0.09%,49.0%,and 73.2%,respectively.AIWW showed a better nutritionscreening effect than NRS-2002 and MST for patients with cancer and could be recommended as an alternative nutritionscreening tool for this population. 展开更多
关键词 nutrition-screening AIWW NRS-2002 MST CANCER
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Effect of Chinese Medicine on No or Slow Reflow after Percutaneous Coronary Intervention in Myocardial Infarction Patients: A Systematic Review and Meta-Analysis 被引量:13
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作者 ZHANG Xiao-yu SUN yang +10 位作者 yang Xin-yu HU Jia-yuan ZHENG Rui CHEN shi-qi LI Min LI Cheng-yu JIANG Yin LIU Shuo ZHAO Chen XING Yan-wei SHANG Hong-cai 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2020年第3期227-234,共8页
Objective:To systematic review the effect of Chinese medicine(CM)on no or slow reflow after percutaneous coronary intervention(PCI)in myocardial infarction(MI)patients.Methods:The Pub Med,EMBASE databases,Cochrane Cen... Objective:To systematic review the effect of Chinese medicine(CM)on no or slow reflow after percutaneous coronary intervention(PCI)in myocardial infarction(MI)patients.Methods:The Pub Med,EMBASE databases,Cochrane Central Register of Controlled Trials(CENTRAL),Web of Science,China National Knowledge Infrastructure(CNKI),Chinese BioMedical Literature Database(CBM),Wanfang Knowledge Service Platform(Wanfang Database)and Chinese Scientific Journal Database(VIP)were searched up to December 2017.Randomized controlled trials(RCTs)which evaluated the effect of CM therapies on no or slow reflow after PCI in MI patients were included.The primary outcome was the effect of reperfusion.Secondary outcomes were left ventricular ejection fraction,incidence of major adverse cardiovascular events and adverse effect.Results:Ten RCTs covering 814 patients were included.Two studies revealed that the incidence of no or slow reflow was less in Shenmai Injection(参麦注射液)group than in the control group measured by thrombolysis in myocardial infarction(TIMI)2(risk ratio=0.55,95%confidence interval 0.38 to 0.81,P=0.003,I^2=37%).Two studies indicated that Salvianolate Injection showed no additional benefit on no or slow reflow measured by corrected TIMI frame count compared with the conventional treatment(mean difference–4.24,95% confidence interval–13.03 to 4.54,P=0.34,I^2=86%).In addition,Tongxinluo Capsules(通心络胶囊),Danhong Injection(丹红注射液)and Xuesaitong Injection(血塞通注射液)may have the potential to reduce no or slow reflow measured during or after PCI in individual studies.Conclusions:Current evidence from RCTs are not sufficient to evaluate the effect of CM adjuvant therapies on no or slow reflow after PCI for MI patients.The included studies are limited by small sample size and unclear baseline conditions.Further rigorously designed researches and verification studies with sufficient number of patients are warranted. 展开更多
关键词 Chinese medicine no reflow phenomenon percutaneous coronary intervention myocardial infarction myocardial reperfusion
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血清生化因素与游离皮瓣重建口腔颌面部缺损血管危象的临床研究 被引量:10
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作者 马振 羊良慧 +5 位作者 房芳 李帅 陈国生 刘诗奇 廖显翔 麦华明 《临床口腔医学杂志》 2019年第11期663-666,共4页
目的:探讨血清生化因子与口腔颌面部缺损游离皮瓣修复血管危象的关系。方法:选取2015年1月~2017年6月接受口腔颌面部游离皮瓣移植术者105例,其中血管危象9例,皮瓣无危象96例。依据回顾性分析结果,将相应的生化因素分为危象组和正常组。... 目的:探讨血清生化因子与口腔颌面部缺损游离皮瓣修复血管危象的关系。方法:选取2015年1月~2017年6月接受口腔颌面部游离皮瓣移植术者105例,其中血管危象9例,皮瓣无危象96例。依据回顾性分析结果,将相应的生化因素分为危象组和正常组。对两组纤维蛋白原、餐后2h血糖、白蛋白、D-2聚体和空腹血糖进行比较分析。结果:高纤维蛋白原、空腹血糖增高、餐后2 h增高的患者发生皮瓣危象的概率均高于正常组,差异具有统计学意义(P<0.05)。Logistic回归分析显示高纤维蛋白原、空腹血糖增高、餐后2 h增高均是血管危象的危险因素(P<0.05)。结论:患者术前高纤维蛋白原、高血糖可能与术后发生皮瓣危象有关。 展开更多
关键词 游离组织皮瓣 血管危象 生化因素
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新型冠状病毒肺炎公众防护意识与行为调查分析 被引量:9
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作者 朱琳 季莉莉 +4 位作者 杨国平 甄世祺 金辉 崔婷婷 徐燕 《华南预防医学》 2021年第2期202-206,共5页
目的了解新型冠状病毒肺炎(新冠肺炎)的公众防护意识及行为情况。方法自行设计调查问卷,于2020年2月15-22日采用方便抽样的方法对来到、返回或居住在江苏省≥15岁居民进行新冠肺炎防控知识及其影响因素调查。采用描述流行病学分析方法... 目的了解新型冠状病毒肺炎(新冠肺炎)的公众防护意识及行为情况。方法自行设计调查问卷,于2020年2月15-22日采用方便抽样的方法对来到、返回或居住在江苏省≥15岁居民进行新冠肺炎防控知识及其影响因素调查。采用描述流行病学分析方法进行分析,并采用单、多因素分析方法对居民新冠肺炎防护知识得分影响因素进行分析。结果共有27410人参与新冠肺炎防护情况调查,受访者中男性占59.50%,31~40岁人群最多(38.83%),67.19%调查对象的防护总得分在90分以上。多因素Logistic回归分析结果显示:女性(OR=1.201),年龄21~30岁、31~40岁、41~50岁(OR=1.302、1.649、1.375),文化程度为高中及中专、大专及以上(OR=1.494、2.526),职业为"政府机关及事业单位、医务工作者、企业、学生"(OR=1.475、2.252、1.205、1.442),居住在城镇(OR=1.152)的防护总得分≥90分的可能性更大(P<0.05);年龄在15~20岁(OR=0.573)居民防护总得分≥90分的可能性较小(P<0.05)。结论较高比例的调查对象已较好掌握新冠肺炎防护知识和技能,但研究结果表明需加强新冠肺炎日常防护知识的宣传和教育,增强日常防护意识,提高健康素养;重点关注男性、年龄20岁以下和51岁以上、文化程度较低、从事商业/服务业和农村人口新冠肺炎的健康知识普及。 展开更多
关键词 新型冠状病毒肺炎 防护 意识 行为
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A new process of extracting vanadium from stone coal 被引量:9
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作者 Yan-hua Liu Chao yang +1 位作者 Pei-you Li shi-qi Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第4期381-388,共8页
A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the... A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the vanadium ore in Fangshankou is difficult to process due to its high consumption of acid and the high leaching rate of impurities. However, the leaching rate can be up to 80% and the content of V2O5 in the residue can be between 0.22%-0.25% in the process of ore fme grinding→oxidation roasting→mixing and ripening→aqueous leaching→P2O4 solvent extraction→sulfuric acid stripping→oxidation and precipitation→decomposition by heat. Also, the quality of flaky V205 produced by this process can meet the requirements of GB3283--87. The total leaching rate of vanadium is 70%. Also, three types of wastes are easy to treat. The vanadium extraction process is better in relation to the aspect of environmental protection than the sodium method. 展开更多
关键词 stone coal VANADIUM EXTRACTION LEACHING solvent extraction V2O5
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基于量表等级化和主成分分析法探究缺血性中风证候要素与治法间关系 被引量:9
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作者 惠小珊 杨帅 +4 位作者 张金生 王阶 袁书章 王诗琦 薛珂 《中国实验方剂学杂志》 CAS CSCD 北大核心 2021年第4期159-167,共9页
目的:运用数据挖掘技术对缺血性中风治法的分布进行研究,评估其临床疗效价值。方法:检索1978年1月至2018年12月中国期刊全文数据库(China National KnowledgeInfrastructure Database,CNKI),维普中文科技期刊数据库(China Science and T... 目的:运用数据挖掘技术对缺血性中风治法的分布进行研究,评估其临床疗效价值。方法:检索1978年1月至2018年12月中国期刊全文数据库(China National KnowledgeInfrastructure Database,CNKI),维普中文科技期刊数据库(China Science and Technology Periodical Database,VIP),万方数据库(Wanfang Data),中国生物医学文献数据库(Chinese Biomedical Literature Database,Sino Med)。基于上述四大数据库内检索有关中医药、中西医结合治疗缺血性中风临床观察、研究文献。对各个文献证候、治法、方药等信息进行规范化、等级化采集处理后建立缺血性中风证候要素与治法数据库。运用量表评价和等级化赋分方法分析证候要素和治法,通过Kendall’s tau-b相关分析、主成分分析等多种统计方法描述缺血性中风证候要素与治法之间、各证候要素间、各治法间的相关性及其分布。结果:通过异质性分析结果显示纳入文献具有同质性、可进行后续统计量的合并。本研究共纳入450条证候、治法,经统一规范化拆分后得到1 287个单一证候要素,1 562个单一治法。各证候要素与其相对应的治法(除窍闭-开窍)均具有较高的相关性,除了相对应的证候要素与治法外,痰湿-益气(-0.52),气虚-开窍(-0.56)也具有较高的相关性。课题组以Ⅰ类,Ⅱ类,Ⅲ类由高至低代表证候和治法要素的重要性。气虚、血瘀和火热、痰湿、腑实是缺血性中风Ⅰ类证候要素;阴虚、内风为其Ⅱ类证候要素;阴虚与阳虚为其Ⅲ类证候要素;袪痰湿、清热、通腑和熄风、活血化瘀、益气是缺血性中风Ⅰ类治法,袪痰湿、清热、通腑相伴出现的可能性较大;熄风、活血化瘀、益气相伴出现的可能性较大。滋阴、理气是缺血性中风Ⅱ类治法,其关联性较高,常相伴出现。开窍、补阳、通络分别为缺血性中风Ⅲ,Ⅳ,Ⅴ类治法。结论:气虚、血瘀、痰湿、火热、腑实是缺血� 展开更多
关键词 缺血性中风 量表评价 等级化赋分 主成分分析 活血化瘀
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PEG-6000模拟干旱胁迫对三种苜蓿种子萌发和幼苗生长的影响 被引量:9
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作者 尚金程 王铭凡 +3 位作者 戴思文 田荷婷 杨诗琪 岳莉然 《黑龙江农业科学》 2021年第7期92-96,共5页
为筛选适宜在北方寒地采石场生态修复中应用的优秀植物材料,以3种苜蓿属种子(紫苜蓿、野苜蓿、花苜蓿)为材料,采用不同PEG-6000浓度(0%、5%、10%、15%和20%)对3种苜蓿属种子进行处理,验证其抗旱性。结果表明:在5%~15%PEG-6000模拟干旱... 为筛选适宜在北方寒地采石场生态修复中应用的优秀植物材料,以3种苜蓿属种子(紫苜蓿、野苜蓿、花苜蓿)为材料,采用不同PEG-6000浓度(0%、5%、10%、15%和20%)对3种苜蓿属种子进行处理,验证其抗旱性。结果表明:在5%~15%PEG-6000模拟干旱胁迫环境下,3种苜蓿属种子发芽势和发芽率无明显降低,而在5%浓度处理下,野苜蓿和花苜蓿种子发芽率有所增长,20%浓度PEG-6000处理,3种苜蓿属种子发芽率和发芽势明显降低。3种苜蓿属种子均有较强抗旱性,其中抗旱性顺序为:花苜蓿>野苜蓿>紫苜蓿。 展开更多
关键词 苜蓿 干旱 种子萌发 幼苗生长
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Nitrous oxide emissions following seasonal freeze-thaw events from arable soils in Northeast China 被引量:8
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作者 CHEN Zhe yang shi-qi +6 位作者 ZHANG Ai-ping JING Xin SONG Wei-min MI Zhao-rong ZHANG qing-wen WANG Wen-ying yang Zheng-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第1期231-246,共16页
Seasonal soil freeze-thaw events may enhance soil nitrogen transformation and thus stimulate nitrous oxide (N2O) emissions in cold regions. However, the mechanisms of soil N2O emission during the freeze-thaw cycling... Seasonal soil freeze-thaw events may enhance soil nitrogen transformation and thus stimulate nitrous oxide (N2O) emissions in cold regions. However, the mechanisms of soil N2O emission during the freeze-thaw cycling in the field remain unclear. We evaluated N2O emissions and soil biotic and abiotic factors in maize and paddy fields over 20 months in Northeast China, and the structural equation model (SEM) was used to determine which factors affected N2O production during non-growing season. Our results verified that the seasonal freeze-thaw cycles mitigated the available soil nitrogen and carbon limitation during spring thawing period, but simultaneously increased the gaseous N2O-N losses at the annual time scale under field condition. The N2O-N cumulative losses during the non-growing season amounted to 0.71 and 0.55 kg N ha 1 for the paddy and maize fields, respectively, and contributed to 66 and 18% of the annual total. The highest emission rates (199.2- 257.4 μg m-2 h-1) were observed during soil thawing for both fields, but we did not observe an emission peak during soil freezing in early winter. Although the pulses of N2O emission in spring were short-lived (18 d), it resulted in approximately 80% of the non-growing season N2O-N loss. The N2O burst during the spring thawing was triggered by the combined impact of high soil moisture, flush available nitrogen and carbon, and rapid recovery of microbial biomass. SEM analysis indicated that the soil moisture, available substrates including NH4+ and dissolved organic carbon (DOC), and microbial biomass nitrogen (MBN) explained 32, 36, 16 and 51% of the N2O flux variation, respectively, during the non-growing season. Our results suggested that N2O emission during the spring thawing make a vital contribution of the annual nitrogen budget, and the vast seasonally frozen and snow-covered croplands will have high potential to exert a positive feedback on climate change considering the sensitive response of nitrogen biogeochemical cycling to 展开更多
关键词 N2O non-growing season nitrogen biogeochemical cycling soil moisture snow cover structural equation model
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Determination of Soil Parameters in Apple-Growing Regions by Near-and Mid-Infrared Spectroscopy 被引量:8
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作者 DONG Yi-Wei yang shi-qi +5 位作者 XU Chun-Ying LI Yu-Zhong BAI Wei FAN Zhong-Nan WANG Ya-Nan LI qiao-Zhen 《Pedosphere》 SCIE CAS CSCD 2011年第5期591-602,共12页
Soil quality monitoring is important in precision agriculture.This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods.A total of 111 soil sampl... Soil quality monitoring is important in precision agriculture.This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods.A total of 111 soil samples were collected from 11 typical sites of apple orchards,and the croplands surrounding them.Near-infrared(NIR) and mid-infrared(MIR) spectra,combined with partial least square regression,were used to predict the soil parameters,including organic matter(OM) content,pH,and the contents of As,Cu,Zn,Pb,and Cr.Organic matter and pH were closely correlated with As and the heavy metals.The NIR model showed a high prediction accuracy for the determination of OM,pH,and As,with correlation coefficients(r) of 0.89,0.89,and 0.90,respectively.The predictions of these three parameters by MIR showed reduced accuracy,with r values of 0.77,0.84,and 0.92,respectively.The heavy metals could also be measured by spectroscopy due to their correlation with organic matter.Both NIR and MIR had high correlation coefficients for the determination of Cu,Zn,and Cr,with standard errors of prediction of 2.95,10.48,and 9.49 mg kg-1 for NIR and 3.69,5.84,and 6.94 mg kg-1 for MIR,respectively.Pb content behaved differently from the other parameters.Both NIR and MIR underestimated Pb content,with r values of 0.67 and 0.56 and standard errors of prediction of 3.46 and 2.99,respectively.Cu and Zn had a higher correlation with OM and pH and were better predicted than Pb and Cr.Thus,NIR spectra could accurately predict several soil parameters,metallic and nonmetallic,simultaneously,and were more feasible than MIR in analyzing soil parameters in the study area. 展开更多
关键词 heavy metals partial least square regression prediction accuracy soil quality spectroscopic method
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稳定同位素标记-高效液相色谱-串联质谱法测定动物源性食品中12种利尿剂
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作者 吴恋 戴琴 +6 位作者 姚静 唐柏杨 廖梅 杨小琪 石培育 陈世奇 宋娟 《化学研究与应用》 CAS 北大核心 2024年第8期1941-1949,共9页
本研究建立了稳定同位素标记-高效液相色谱串联质谱法测定动物源性食品中12种利尿剂的方法。试样经5%甲酸乙腈提取,通过式固相萃取柱净化,采用液相色谱-质谱/质谱仪测定,同位素内标法定量。12种利尿剂在各自浓度范围内线性关系良好,平... 本研究建立了稳定同位素标记-高效液相色谱串联质谱法测定动物源性食品中12种利尿剂的方法。试样经5%甲酸乙腈提取,通过式固相萃取柱净化,采用液相色谱-质谱/质谱仪测定,同位素内标法定量。12种利尿剂在各自浓度范围内线性关系良好,平均回收率介于71.3%~104.7%,相对标准偏差介于1.2%~11.1%(n=6)。该方法具有灵敏度高、准确性好、操作简单、检测效率高等特点,能够满足多种动物源性食品中12种利尿剂的检测需求。 展开更多
关键词 高效液相色谱-串联质谱 动物源性食品 利尿剂 稳定同位素标记
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一株高产纤维素酶真菌的分离与鉴定 被引量:6
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作者 尹守亮 杨镒婴 +3 位作者 李秋园 杨何宝 郭世奇 周志江 《纤维素科学与技术》 CAS 2022年第2期9-18,共10页
纤维素类生物质是地球上分布最为广泛的可再生资源,筛选高效的纤维素降解菌株对于纤维素生物质资源的开发和利用具有重要的意义。采用微晶纤维素作为唯一碳源的筛选方法,从曹妃甸湿地土壤样品中分离到一株高产纤维素酶的真菌,通过对菌... 纤维素类生物质是地球上分布最为广泛的可再生资源,筛选高效的纤维素降解菌株对于纤维素生物质资源的开发和利用具有重要的意义。采用微晶纤维素作为唯一碳源的筛选方法,从曹妃甸湿地土壤样品中分离到一株高产纤维素酶的真菌,通过对菌株形态学特征观察和18SrDNA序列比对分析,鉴定其为土曲霉种属。发酵检测该菌株粗酶液中含有较高活性的外切葡聚糖酶和β-葡萄糖苷酶,活力大小分别为110.7、167.7U/mL;其内切葡聚糖酶和滤纸酶酶活力分别为27.8、51.5U/mL,土曲霉CB10可作为潜在的开发菌种用于纤维素生物降解的研究。 展开更多
关键词 纤维素 唯一碳源 纤维素酶 形态特征 18S rDNA 土曲霉 酶学活性
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基于FY3C地表温度重建的多云地区旱情监测评估 被引量:7
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作者 张德军 杨世琦 +4 位作者 王永前 孙亮 高阳华 祝好 叶勤玉 《自然资源学报》 CSSCI CSCD 北大核心 2021年第4期1047-1061,共15页
受热红外传感器无法探测云下地表信息的影响,热红外遥感数据失去了对多云地区旱情监测的能力。采用RSDAST(Remotely Sensed Daily Land Surface Temperature Reconstruction)模型实现了FY3C/VIRR(Visible and Infrared Radiometer)云像... 受热红外传感器无法探测云下地表信息的影响,热红外遥感数据失去了对多云地区旱情监测的能力。采用RSDAST(Remotely Sensed Daily Land Surface Temperature Reconstruction)模型实现了FY3C/VIRR(Visible and Infrared Radiometer)云像元LST值的重建,结合重建后LST和NDVI数据采用TVDI指数对2018年重庆市干旱进行监测分析,并通过对比土壤墒情数据与OTVDI(Original TVDI)和RTVDI(Reconstructed TVDI)间的相关性来评估RTVDI在多云条件下旱情监测的能力。评估结果表明:基于RSDAST模型扩大了多云地区遥感干旱监测的空间范围和时间连续性,提升了区域旱情监测的精度(长时间序列和空间分布上RTVDI与土壤墒情数据间的R值均高于OTVDI),极大地提高热红外遥感数据在多云条件下的可用性和可靠性。 展开更多
关键词 可见光遥感 地表温度重建 RSDAST 干旱
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Constructing core@shell structured photothermal nanosphere with thin carbon layer confined Co-Mn bimetals for pollutant degradation and solar interfacial water evaporation
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作者 Hong-yang Zhu Meng-Ting Liu +9 位作者 Gang Wang Rong-Rong Du Hong-Yao Zhao Hao Lu shi-qi yang Sheng Tang Zeng-Jing Guo Jun yang Cheng-Zhang Zhu Fu yang 《Rare Metals》 SCIE EI CAS CSCD 2024年第4期1686-1701,共16页
Photothermal material applied in environmental governance has attracted growing attention.By combining the Stober method and dopamine-triggered coating strategy,Co-Mn precursor was in situ incorporated into the poly d... Photothermal material applied in environmental governance has attracted growing attention.By combining the Stober method and dopamine-triggered coating strategy,Co-Mn precursor was in situ incorporated into the poly dopamine(PDA)layer over the surface of silica cores.Afterwards,a unique photothermal nanosphere with SiO_(2)core and thin carbon layer and dual Co-Mn oxides shell was allowed to form by sequential heat treatment in the inert atmosphere(SiO_(2)@CoMn/C).The bimetallic fraction of Co/Mn in the carbon layer and post-treatment calcination temperature was comprehensively tuned to optimize the peroxymonosulfate(PMS)activation performance of the catalyst.The state of bimetallic species was studied including their physical distribution,chemical valence,and interplay by various characterizations.Impressively,Co oxides appear as dominant monodispersed nanoparticles(~10 nm),while Mn with cluster-like morphology is observed to uniformly distribute over thin-layer carbon and adhered to the surface of SiO_(2)nanospheres(~250 nm).The calcined temperature could tune the oxidized state of Co species,leading to the optimization of the catalytic performance of introduced dual metal species.As a result,this obtained optimal catalyst integrated the advantages of exposed bimetallic CoMn species and N-doped thin carbon to deliver excellent catalytic PMS activation performance and photothermal synergetic catalytic mineralization ability for diversiform pollutants.Further reactions condition controls and anion interference studies were conducted to identify the adaptability of the optimal catalyst.Moreover,the application of solar-driven interfacial water evaporation using optimal SiO_(2)@Co_3Mn_1/C-600 catalyst was explored,showing a high water evaporation rate of 1.48 kg·m^(-2)·h^(-1)and an efficiency of 95.2%,further revealing a comprehensive governance functionality of obtained material in the complex pollution condition. 展开更多
关键词 PHOTOTHERMAL Peroxymonosulfate(PMS)activation Bimetallic synergy Water evaporation Advanced oxidation process
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Effects and mechanism of igneous rock on selenium in the tropical soil-rice system in Hainan Province, South China 被引量:6
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作者 Xiu-jin Liu Ke yang +5 位作者 Fei Guo shi-qi Tang Ying-han Liu Li Zhang Hang-xin Cheng Fei Liu 《China Geology》 2022年第1期1-11,共11页
To illuminate the migration and transformation of selenium(Se)in the igneous rock-soil-rice system,285 pairs of rhizosphere soil and rice samples were collected from the granitoid and basalt areas in Hainan Province,S... To illuminate the migration and transformation of selenium(Se)in the igneous rock-soil-rice system,285 pairs of rhizosphere soil and rice samples were collected from the granitoid and basalt areas in Hainan Province,South China.The contents of Se in soils derived from granitoid and basalt are,respectively,0.19±0.12 mg/kg and 0.34±0.39 mg/kg,which are much higher than Se contents in granitoid and basalt.Selenium shows remarkable enrichment from granitoid and basalt to soils.The mobile fraction of Se in soils derived from granitoid is 0.0100±0.0034 mg/kg,which is significantly higher than that of basalt(0.0058±0.0039 mg/kg).Although soil derived from basalt shows higher Se contents,Se contents in rice samples,mobile fractions of Se in soils,and biological concentration factor(BCF)is similar or even lower than that from granitoid.Basalt consist of calcic plagioclase and pyroxene,and are much richer in Fe,Al,and Ca than granitoid.Correspondingly,the basalt-derived soils have higher goethite,hematite,kaolinite,cation exchange capacity(CEC)content,and higher p H than the granitoid-derived soils,which result in higher adsorption capacity for Se and relatively lower Se bioavailability.Soils derived from granitoid and basalt in tropical regions are beneficial to produce Se-rich rice. 展开更多
关键词 SELENIUM GRANITOID BASALT Soil properties Tropical soil Se-rich rice Agricutural geological survey engineering Hainan Province China
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