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人参潜在地理分布以及气候变化对其影响预测 被引量:38
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作者 赵泽芳 卫海燕 +1 位作者 郭彦龙 顾蔚 《应用生态学报》 CAS CSCD 北大核心 2016年第11期3607-3615,共9页
本文以人参为研究对象,基于人参分布点位数据和22个气候环境因子数据,运用BioMod2平台10个物种分布模型对当前我国东北地区人参潜在生境分布进行预测.以受试者工作特征曲线(ROC)为权重集成10个模型的模拟结果,构建组合模型,并基于该模... 本文以人参为研究对象,基于人参分布点位数据和22个气候环境因子数据,运用BioMod2平台10个物种分布模型对当前我国东北地区人参潜在生境分布进行预测.以受试者工作特征曲线(ROC)为权重集成10个模型的模拟结果,构建组合模型,并基于该模型预测了IPCC第五次评估报告中RCP 8.5、RCP 6.0、RCP 4.5和RCP 2.6等4种排放情景下21世纪50和70年代人参潜在分布范围.结果表明:在基准气候条件下,人参适宜生境面积占研究区总面积的10.4%,此类地区主要分布于研究区东北部长白山地区以及小兴安岭东南部区域的森林地带.在未来不同的排放情景下研究区人参的适宜生境变化显著,总体上分布范围将有一定程度的缩小.同时参与建模的10种模型在统计学精度、预测结果以及变量权重上都有差异.模型精度计算结果表明,MAXENT模拟效果最好,GAM、RF和ANN次之,SRE模拟精度最低.本文构建的组合模型在一定程度上提高了现有物种分布模型的预测精度,从而使模拟效果更优. 展开更多
关键词 气候变化 bio Mod2 组合模型 人参
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基于PacBio平台的全长转录组测序 被引量:18
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作者 任毅鹏 张佳庆 +6 位作者 孙瑜 吴振峰 阮吉寿 贺秉军 刘国卿 高山 卜文俊 《科学通报》 EI CAS CSCD 北大核心 2016年第11期1250-1254,共5页
当前,绝大多数的转录组数据都是基于以Illumina平台为代表的第二代高通量测序技术获得的,但是第二代测序技术无法提供大量的长转录本并且丢失可变剪接等重要信息,因而大大制约了转录组数据的深度利用.通过以PacBio为代表的第三代测序技... 当前,绝大多数的转录组数据都是基于以Illumina平台为代表的第二代高通量测序技术获得的,但是第二代测序技术无法提供大量的长转录本并且丢失可变剪接等重要信息,因而大大制约了转录组数据的深度利用.通过以PacBio为代表的第三代测序技术,可以获得更长乃至全长转录组,但由于Pac Bio转录组测序近几年才刚兴起,只有少量的物种基于PacBio平台获得了转录组.PacBio全长转录组测序,在国际上才刚开展但发展很快,其实验与数据分析标准和质量控制方面的研究对于未来的大规模应用至关重要.本研究在国际上首次尝试依据PacBio平台最新试剂(P6/C4)优化实验参数,设计质量控制指标并使全长转录组测序标准化.本文基于一组昆虫(麻皮椿)全长转录组数据,对已取得的部分结果进行报告. 展开更多
关键词 全长转录组 单分子测序 PAC bio 质量控制 标准流程
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受污染景观水体的生物修复 被引量:10
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作者 潘涌璋 张娜 +2 位作者 叶林顺 谭淑英 李秀玉 《环境污染治理技术与设备》 CAS CSCD 北大核心 2005年第3期69-71,共3页
应用生物刺激剂BIOE1对受污染的人工景观池水进行生物修复试验。现场试验的结果表明,生物刺激剂BIOE1能有效地对受污染的景观池水进行生物修复,处理后的池水清澈,水体中的溶解氧浓度显著提高,CODCr、氨氮、总磷和浊度的去除率分别为68%... 应用生物刺激剂BIOE1对受污染的人工景观池水进行生物修复试验。现场试验的结果表明,生物刺激剂BIOE1能有效地对受污染的景观池水进行生物修复,处理后的池水清澈,水体中的溶解氧浓度显著提高,CODCr、氨氮、总磷和浊度的去除率分别为68%、93%、75%和83%。所用生物刺激剂不含外来微生物,对人体和鱼类无毒性。 展开更多
关键词 生物修复 污染 景观水体 溶解氧浓度 COD 去除率 氨氮 生物刺激 bio 池水
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贝奥雄性不育灭鼠剂室内药效试验 被引量:14
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作者 尤德康 董晓波 +3 位作者 宋玉双 李继成 孙永吉 蒋永利 《中国森林病虫》 北大核心 2006年第2期32-34,共3页
贝奥雄性不育灭鼠剂是一种新型的植物源灭鼠剂,来源于天然植物雷公藤。本试验通过在室内用该药剂喂饲金黄地鼠,检验其对雄鼠的不育作用,结果表明该植物源药剂对雄性金黄地鼠具有显著的不育效果。
关键词 贝奥 雄性不育 灭鼠剂 药效试验
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Gene expression signatures for phlegm-dampness constitution of Chinese Medicine 被引量:16
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作者 Lingru Li Juan Feng +12 位作者 Haiqiang Yao Lan Xie Yu Chen Lingling Yang Shujuan Hou Shipeng Zhao Ranran Sun Yanling Wu Tongtong Bai Yingshuai Li Ruoxi Yu Ji Wang Qi Wang 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第1期105-107,共3页
Dear Editor, The term "individualized medicine" was first used in Bio- chemistry Individuality in 1956 by Williams (Williams et al., 1956). With the emergence of the post-genome era in the 21 st century, individua... Dear Editor, The term "individualized medicine" was first used in Bio- chemistry Individuality in 1956 by Williams (Williams et al., 1956). With the emergence of the post-genome era in the 21 st century, individualized precision medicine has attracted increasing attention. In traditional Chinese medicine (TCM), there is also concept of individualized medicine, which is known as the Chinese constitutional theory, proposed in the 1970s (Wang, 2012). According to this theory, the human population is divided into nine constitutions, including one balanced constitution (Normality) and eight unbalanced constitutions (Yang-deficient, Yin-deficient, Qi-deficient, 展开更多
关键词 中医学 体质 基因表达 特征 后基因组时代 构成要件 不平衡 bio
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Effect of dietary interventions on the intestinal microbiota of Mongolian hosts 被引量:15
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作者 Jing Li Haiyan Xu +8 位作者 Zhihong Sun Qiangchuan Hou Lai-Yu Kwok Wuri Laga Yanjie Wang Huimin Ma Zhongjie Yu Bilige Menghe Heping Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2016年第20期1605-1614,共10页
The gut microbiota of Mongolian hosts has distinctive characteristics due to their meat- and dairyoriented daily diets and unique genotype.The aim of the present study was to investigate the effect of switching from t... The gut microbiota of Mongolian hosts has distinctive characteristics due to their meat- and dairyoriented daily diets and unique genotype.The aim of the present study was to investigate the effect of switching from the typical high protein and fat Mongolian diets to carbohydrate-rich meals composed principally of wheat,rice and naked oats on the host gut microbiota within 3 weeks.Our study took the advantage of the long sequence reads produced by the Pac Bio single molecule real-time sequencing technology to enable the profiling of subjects' gut microbiota communities along the diet intervention to the species precision.We found that the bacterial richness and diversity decreased apparently along the diet intervention.During the diet intervention,the gut microbiota composition displayed no significant difference at phylum level(with major phyla of Firmicutes,Bacteroidetes,Tenericutes and Proteobacteria).The relative abundances of some genera such as Bacteroidetes,Faecalibacterium,Roseburia,Alistipes,Streptococcus,and Oscillospira were significantly altered after the diet switching started.Notably,significant changes were also observed in the proportions of the species Bacteroides dorei,Bacteroides fragilis,Bacteroides thetaiotaomicron,Ruminococcus albus,Ruminococcus faecis,Roseburia faecis and Eubacterium ventriosum.These results have demonstrated that diet and host gut microbiota is closely linked. 展开更多
关键词 Gut microbiota Diet intervention MONGOLIAN Pac bio single molecule real-time sequencing technology(SMRT sequencing)
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Effects of a conversion from grassland to cropland on the different soil organic carbon fractions in Inner Mongolia, China 被引量:13
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作者 QI Yuchun DONG Yunshe +6 位作者 PENG Qin XIAO Shengsheng HE Yating LIU Xinchao SUN Liangjie JIA Junqiang YANG Zhijie 《Journal of Geographical Sciences》 SCIE CSCD 2012年第2期315-328,共14页
Cultivation is one of the most important human activities affecting the grassland ecosystem besides grazing, but its impacts on soil total organic carbon (C), especially on the liable organic C fractions have not be... Cultivation is one of the most important human activities affecting the grassland ecosystem besides grazing, but its impacts on soil total organic carbon (C), especially on the liable organic C fractions have not been fully understood yet. In this paper, the role of cropping in soil organic C pool of different fractions was investigated in a meadow steppe region in Inner Mongolia of China, and the relationships between different C fractions were also discussed. The results indicated that the concentrations of different C fractions at steppe and cultivated land all decreased progressively with soil depth. After the conversion from steppe to spring wheat field for 36 years, total organic carbon (TOC) concentration at the 0 to 100 cm soil depth has decreased by 12.3% to 28.2%, and TOC of the surface soil horizon, especially those of 0-30 cm decreased more significantly (p〈0.01). The dissolved organic carbon (DOC) and microbial biomass carbon (MBC) at the depth of 0-40 cm were found to have decreased by 66.7% to 77.1% and 36.5% to 42.4%, respectively. In the S.baicalensis steppe, the ratios of soil DOC to TOC varied between 0.52% and 0.60%, and those in the spring wheat field were only in the range of 0.18%-0.20%. The microbial quotients (qMBs) in the spring wheat field, varying from 1.11% to 1.40%, were also lower than those in the S. baicalensis steppe, which were in the range of 1.50%-1.63%. The change of DOC was much more sensitive to cultivation disturbance. Soil TOC, DOC, and MBC were significantly positive correlated with each other in the S. baicalensis steppe, but in the spring wheat field, the correlativity between DOC and TOC and that between DOC and MBC did not reach the significance level of 0.05. 展开更多
关键词 temperate grassland cultivation soil total organic carbon dissolved organic carbon microbial bio- mass carbon
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指纹显现技术的现状与发展趋势(英文) 被引量:13
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作者 马荣梁 《刑事技术》 2016年第4期302-308,共7页
本文旨在总结指纹技术的新发展,并从以下10个方面分析指纹技术未来发展的可能方向。1.更灵敏的显现试剂。以荧光试剂和纳米粒子为代表的两种技术最为重要和突出。纳米粒子较常规粉末吸附性好,而荧光试剂具有高灵敏度且能克服背景干扰的... 本文旨在总结指纹技术的新发展,并从以下10个方面分析指纹技术未来发展的可能方向。1.更灵敏的显现试剂。以荧光试剂和纳米粒子为代表的两种技术最为重要和突出。纳米粒子较常规粉末吸附性好,而荧光试剂具有高灵敏度且能克服背景干扰的优点,二者结合表现更加显著,有关研究表明其前景广阔。2.疑难客体上的指纹显现技术。指皮肤、胶带粘面、塑料纸币及背景发荧光的材质等表面上的指纹显现。3.时间分辨和相分辨技术。它们都涉及到一系列复杂仪器的使用,另外与传统荧光使用不同,时间分辨技术是根据指纹试剂及背景的荧光寿命或者相位的不同,通过复杂仪器分辨出该微小差异并加以放大,从而将指纹显现出来。此方法能显现传统荧光法处理不了的指纹。4.光谱成像技术。包括红外、紫外及可见光、拉曼成像等。光谱成像技术特别是红外光谱成像技术在显现指纹的同时,能够分辨出指纹物质的成分,比如手上粘附的一些外源性物质像毒品、爆炸残留物等。因而,光谱成像技术可能是迄今为止最为有效的能解决一些疑难指纹显现的技术,但光谱成像一般需要大型昂贵的仪器设备。5.生化核危害性物质污染的检材上的手印显现。甲醛处理生化类污染的指纹检材有报道,但核污染材料本文未涉及。6.免疫学和适配体技术。使用抗原抗体的免疫学反应来显现指纹也是人们探索的重要方向之一。免疫学和适配体技术都具有高灵敏度和选择性强的优点,但反应条件较为苛刻。7.指纹来源的情报信息获取。从指纹中探测毒品、爆炸残留物等信息属于指纹信息学的范畴。此外,指纹自动识别系统的指纹信息也是侦查破案所需的重要情报信息。8.指纹鉴定及三级特征的应用。现有指纹鉴定是以二级特征数量为标准的,但在实际案件中,常有二级特征不足的情 展开更多
关键词 指纹 指纹显现 时间分辨与相分辨 生化核危害性物质 物证情报 第3级特征 指纹遗留时间的估测 计算机指纹自动识别系统
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中国酶工程的兴旺与崛起 被引量:10
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作者 黎高翔 《生物工程学报》 CAS CSCD 北大核心 2015年第6期805-819,共15页
酶工程是生物工程的重要组成部分,工业生物催化技术被认为是继医药、农业之后的第三个浪潮。在25年中,中国在酶工程领域研究中取得很大进展,本综述集中介绍在中国酶工程会议上,酶的基因工程、酶的蛋白质工程、生物合成、微生物转化和生... 酶工程是生物工程的重要组成部分,工业生物催化技术被认为是继医药、农业之后的第三个浪潮。在25年中,中国在酶工程领域研究中取得很大进展,本综述集中介绍在中国酶工程会议上,酶的基因工程、酶的蛋白质工程、生物合成、微生物转化和生物传感器方面的成果和我国酶制剂工业的进展。 展开更多
关键词 酶工程 生物技术 工业生物催化 酶基因组学 酶蛋白质组学 生物合成 微生物转化 生物传感器 酶制剂
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Cryogenic Thermophysical Studies for Clinical Medicine 被引量:8
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作者 华泽钊 《Tsinghua Science and Technology》 SCIE EI CAS 2002年第2期165-170,共6页
Cryogenic technology has been widely used in clinical medicine and in pharmaceutics, so thermophysical studies are extremely important to solve problems during freezing and thawing. This paper reports some recent r... Cryogenic technology has been widely used in clinical medicine and in pharmaceutics, so thermophysical studies are extremely important to solve problems during freezing and thawing. This paper reports some recent research in clinical medicine, including cryo injury, cryosurgery, and cryopreservation of some important cells and tissues. Microscopic images of the freezing process with a cryomicroscope system show that the dendritic ice growth is affected by the solution concentration, the cooling rate, and the number of embryos. An enthalpy method is used for the freeze thaw analysis of the cryosurgery with a program developed to predict the temperature profile and the interface motion, which compares well with experimental results. A very rapid cooling technique is developed by quenching the samples into subcooled liquid nitrogen for vitrification of cells and tissues. An analytical method developed to prevent the fracture of arteries during freezing has been verified by the electronic microscopic investigation. 展开更多
关键词 bio heat transfer CRYObioLOGY CRYOPRESERVATION CRYOSURGERY quenching boiling
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基于SMRT测序技术的16S rRNA基因全长测序及其分析方法 被引量:8
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作者 唐勇 刘旭 《生物技术通报》 CAS CSCD 北大核心 2017年第8期34-39,共6页
被称为第三代测序技术的单分子测序是最近几年发展起来的高通量测序技术。其中,由Pacbio Bio Sciences公司开发的单分子实时测序技术(SMRT)是最先商用的技术。SMRT测序技术通过对模板序列循环测序产生环形一致序列(CCS),成功克服第三代... 被称为第三代测序技术的单分子测序是最近几年发展起来的高通量测序技术。其中,由Pacbio Bio Sciences公司开发的单分子实时测序技术(SMRT)是最先商用的技术。SMRT测序技术通过对模板序列循环测序产生环形一致序列(CCS),成功克服第三代测序技术准确率低的弊病。通过SMRT测序技术,科学家可以更深入准确地探究复杂环境微生物的结构和功能。介绍SMRT测序技术在微生物16S rRNA基因测序中的优势和劣势,并就基于SMRT测序技术所得的全长16S rRNA基因序列的质量控制、错误序列排除、聚类和注释分析等重要分析环节进行概述,同时,提出利用SMRT测序技术研究复杂环境微生物可能存在的问题及其解决方法,期望能为研究人员提供参考。 展开更多
关键词 单分子实时测序技术 PAC bio RSⅡ 第三代测序技术 环形一致序列
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Overview of In—Situ Biodegradation and Enhancement 被引量:4
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作者 DONG Jun, Anthony ADZOMANI and ZHAO Yongsheng(College of Environment and Resources, Jilin University, Changchun 130026, P. R.China) 《Global Geology》 2002年第1期72-78,104,共8页
Microbial degradation technologies have been developed to restore ground water quality in aquifers polluted by organic contaminants effectively in recent years. However, in course of the degradation, the formation of ... Microbial degradation technologies have been developed to restore ground water quality in aquifers polluted by organic contaminants effectively in recent years. However, in course of the degradation, the formation of biofilms in ground water remediation technology can be detrimental to the effectiveness of a ground water remediation project. Several alternatives are available to a remedial design engineer, such as Permeable Reactive Barriers (PRBs) and in -situ bioremediation, Hydrogen Releasing Compounds (HRCs) barrier, Oxygen Releasing Compounds (ORCs) barrier etc. which are efficient and cost- effective technologies. Excessive biomass formation renders a barrier ineffective in degrading the contaminants, Efforts are made to develop kinetics models which accurately determine bio - fouling and bio - filn formation and to control excessive biomass formation. 展开更多
关键词 PERMEABLE Reactive Barriers (PRBs) Oxygen RELEASING COMPOUNDS (ORCs) barrier Hydrogen RELEASING COMPOUNDS (HRCs) barrier bioremediation bio - film bio - fouling.
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矮牵牛转基因体系的建立及转BIO和bio基因研究初报 被引量:4
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作者 李颖 刘姬艳 +3 位作者 胡江琴 陈哲皓 胡灵芝 王利琳 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2013年第1期42-49,共8页
BIO ORGANS(BIO)是百脉根中调控器官形态及大小的基因。首先改良了矮牵牛愈伤诱导和再生体系,并进一步利用根癌农杆菌介导法定向将BIO及其突变基因bio导入矮牵牛中进行功能研究。结果证实含0.1mg/L6-BA的MS培养基有利于矮牵牛组培苗的增... BIO ORGANS(BIO)是百脉根中调控器官形态及大小的基因。首先改良了矮牵牛愈伤诱导和再生体系,并进一步利用根癌农杆菌介导法定向将BIO及其突变基因bio导入矮牵牛中进行功能研究。结果证实含0.1mg/L6-BA的MS培养基有利于矮牵牛组培苗的增殖,添加了1.0mg/L 6-BA和0.1mg/L NAA的MS培养基有利于愈伤以及不定芽的诱导。对转基因植株目的基因的PCR检测结果显示,BIO及其突变基因bio被成功转入了矮牵牛中。表型观察结果显示:转BIO及其突变基因bio的植株叶片边缘均呈现不规则形态,部分叶片缺刻,出现由一个叶片向两个叶片分裂的趋势。其中转BIO基因植株部分叶片面积减小,叶片变窄或几乎只剩主叶脉。该研究证实BIO基因对保持叶片器官形态起到关键的作用,从而为进一步探索BIO基因的调控机制提供了实验依据。 展开更多
关键词 矮牵牛 bio ORGANS基因(bio) 组织培养 遗传转化
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Impaired contractility and remodeling of the upper gastrointestinal tract in diabetes mellitus type-1 被引量:8
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作者 Jens BrΦndum FrΦkjΦr SΦren Due Andersen +3 位作者 Niels EjskjΦr Peter Funch-Jensen AsbjΦrn Mohr Drewes Hans Gregersen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第36期4881-4890,共10页
AIM: To investigate that both the neuronal function of the contractile system and structural apparatus of the gastrointestinal tract are affected in patients with longstanding diabetes and auto mic neuropathy. METHODS... AIM: To investigate that both the neuronal function of the contractile system and structural apparatus of the gastrointestinal tract are affected in patients with longstanding diabetes and auto mic neuropathy. METHODS: The evoked esophageal and duodenal contractile activity to standardized bag distension was assessed using a specialized ultrasound-based probe. Twelve type-1 diabetic patients with autonomic neuropathy and severe gastrointestinal symptoms and 12 healthy controls were studied. The geometry and biomechanical parameters (strain, tension/stress, and stiffness) were assessed. RESULTS: The diabetic patients had increased frequency of distension-induced contractions (6.0 ± 0.6 vs 3.3 ± 0.5, P < 0.001). This increased reactivity was correlated with the duration of the disease (P = 0.009). Impaired coordination of the contractile activity in diabetic patients was demonstrated as imbalance between the time required to evoke the first contraction at the distension site and proximal to it (1.5 ± 0.6 vs 0.5 ± 0.1, P = 0.03). The esophageal wall and especially the mucosa-submucosa layer had increased thickness in the patients (P < 0.001), and the longitudinal and radial compressive stretch was less in diabetics (P <0.001). The esophageal and duodenal wall stiffness and circumferential deformation induced by the distensions were not affected in the patients (all P > 0.14). CONCLUSION: The impaired contractile activity with an imbalance in the distension-induced contractions likely reflects neuronal abnormalities due to autonomic neuropathy. However, structural changes and remodeling of the gastrointestinal tract are also evident and may add to the neuronal changes. This may contribute to the pathophysiology of diabetic gut dysfunction and impact on future management of diabetic patients with gastrointestinal symptoms. 展开更多
关键词 Diabetes Autonomic Neuropathy bio- mechanics CONTRACTILITY Ultrasound ESOPHAGUS DUODENUM Deformation Stress
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Cardiac Tolerance of Hydroalcoholic Extract of Bark of Terminalia mantaly H. Perrier (HAEBTM) in Wistar Rats
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作者 Irié Lou Bohila Emilie Kamo Kouakou Serge Kouassi +3 位作者 Virginie Atto Allico Joseph Djaman Jean David N’guessan Mireille Dosso 《American Journal of Molecular Biology》 CAS 2024年第3期126-137,共12页
Terminalia mantaly H. Perrier is a plant used in traditional medicine for the treatment of various pathologies. However, Terminalia mantaly H. Perrier could present potential health effects on patients. In order to de... Terminalia mantaly H. Perrier is a plant used in traditional medicine for the treatment of various pathologies. However, Terminalia mantaly H. Perrier could present potential health effects on patients. In order to determine the possible cardiotoxic effects of the hydro-alcoholic extract of the bark of Terminalia mantaly H. Perrier, (HAEBTM) forty (40) rats distributed randomly into 4 groups, including 10 animals per group (5 males and 5 females) were used. Animals in group 1 received distilled water and were used as a control group. On the other hand, groups 2, 3, 4 received oral administration a volume of the hydroalcoholic extract of Terminalia mantaly H. Perrier corresponding to 1 mL/100g of body weight at 150 mg/kg, 300 mg/kg, 600 mg/kg, respectively. The extract was administered daily at the same time for 28 days and serum was collected once a week to evaluate cardiac biochemical markers using spectrophotometric methods using a Cobas C311 HITACHI biochemistry system. After one month of study, all rats were euthanized by overdose of ether, and the hearts of the rats were removed for gross morphological and histopathological analysis. Results were analysed using variance analysis (ANOVA) to compare outcomes as a function of doses administered and treatment times. The biochemical parameters ALT, LDH, CPK, CPKMB showed no significant change (p Terminalia mantaly showed no lesions, edema and necrosis. These results suggest that the hydroalcoholic extract of Terminalia mantaly did not interfere with the functioning or alter the integrity of the heart. 展开更多
关键词 Terminalia mantaly bio Cardiac Tolerance biochemical Markers HISTOPATHOLOGY
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NATURAL GAS OF NEW GENETIC TYPE——BIO-, THERMO-CATALYTIC TRANSITIONAL ZONE GAS 被引量:5
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作者 徐永昌 沈平 +1 位作者 刘文汇 王万春 《Science China Chemistry》 SCIE EI CAS 1991年第9期1113-1119,共7页
Bio-, thermo-catalytic transitional zone gas (BTCTZ gas), of which burial depth is shallow (1000-2500m), chemical composition (C,/ΣC1-5 = 0.7-0.9) and isotopic composition (δ13C1= -55 to-48‰) coincide with the evol... Bio-, thermo-catalytic transitional zone gas (BTCTZ gas), of which burial depth is shallow (1000-2500m), chemical composition (C,/ΣC1-5 = 0.7-0.9) and isotopic composition (δ13C1= -55 to-48‰) coincide with the evolution level of organic matter (R0=0.25-0.6%) in the corresponding strata, is a natural gas of new genetic type. The genesis of BTCTZ gas must have some relation to microcatalysis under lower temperature and condensation of aromatic hydrocarbons. In line with the new theory of natural gas formation, the existence of BTCTZ gas is objective. According to data from all over the world, BTCTZ gas may hold an important position in the table of reserves of natural gas. 展开更多
关键词 GENETIC type of natural GAS bio- thermo-catalytie transitional zone GAS (BTCTZ gas) GAS formation mechanism HUMIC organic matter.
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Hydrolysable Chestnut Tannin Extract Chemical Complexity in Its Reactions for Non-Isocyanate Polyurethanes(NIPU)Foams 被引量:1
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作者 Elham Azadeh Antonio Pizzi +1 位作者 Christine Gerardin-Charbonnier Philippe Gerardin 《Journal of Renewable Materials》 SCIE EI 2023年第6期2823-2848,共26页
Non-isocyanate polyurethane(NIPU)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions inv... Non-isocyanate polyurethane(NIPU)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions involved.This method is based on two main steps:the reaction with dimethyl carbonate and the formation of urethane bonds by further reaction of the carbonated tannin with a diamine-like hexamethylene diamine.The hydroxyl groups on the tannin polyphenols and on the carbohydrates intimately linked with it and part of a hydrolysable tannin are the groups involved in these reactions.The carbohydrate skeleton of the hydrolysable tannin is also able to participate through its hydroxyl groups to the same two reactions rendering the whole molecular complex able to react to form NIPUs.The analysis by Matrix-Assisted Laser Desorption Ionization(MALDI-TOF)mass spectrometry and 13C Nuclear Magnetic Resonance(13C NMR)to further investigate the reaction mechanisms involved revealed the unsuspected complexity of chestnut hydrolysable tannin,with different fragments reacting in different manners forming a hardened network of considerable complexity.As the morphology and performance of these types of foams changes slightly with the change in the amount of glutaraldehyde and hexamine hardeners,the best performing foam formulation previously determined was scanned by SEM and analysed chemically for the structures formed. 展开更多
关键词 Hydrolysable tannin chestnut tannin non-isocyanate bio polyurethanes NIPU MALDI-TOF ^(13)C NMR SEM bio-based materials
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贝奥雄性不育灭鼠剂防治两种害鼠试验 被引量:6
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作者 尤德康 宋玉双 +3 位作者 蒋永利 潘竟军 柴守权 董晓波 《中国森林病虫》 北大核心 2010年第6期46-49,共4页
贝奥雄性不育灭鼠剂防治棕背Clethrionomys rufocanus和大沙鼠Rhombomys opimus试验表明,防治棕背采用1次投药11.25 kg/hm2,防治效果达83%以上;防治大沙鼠用"贝奥"母粉与饵料(胡萝卜+香油)1.25∶1 000配制为推荐量。
关键词 贝奥 雄性不育 灭鼠剂 棕背 大沙鼠 防治试验
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Extrusion-base d 3D-printe d“rolle d-up”composite scaffolds with hierarchical pore structure for bone growth and repair
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作者 Yufan Li Li Chen +6 位作者 Yijing Stehle Mingyue Lin Chenxin Wang Rui Zhang Min Huang Yubao Li Qin Zou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第4期222-234,共13页
Three-dimensional(3D)bioprinting,specifically direct ink writing(DIW)capable of printing biologically active substances such as growth factors or drugs under low-temperature conditions,is an emerging di-rection in bon... Three-dimensional(3D)bioprinting,specifically direct ink writing(DIW)capable of printing biologically active substances such as growth factors or drugs under low-temperature conditions,is an emerging di-rection in bone tissue engineering.However,limited by the bio-ink mobility and the poor resolution of this printing technology,the lateral pores of current crisscross-stacked scaffolds printed through DIW tend to clog and are inimical to bone growth.Therefore,it is critical to develop DIW printed biologi-cal scaffold structure with high mechanical strength,porosity,and biocompatibility performance.Herein,patterned polylactic acid(PLA)/polycaprolactone(PCL)/nano-hydroxyapatite(n-HA)based scaffold was printed through DIW technological and rolled-up for properties characterization,cytocompatibility test,and bone repair experiment.The result not only shows that the hexagonal patterned scaffolds are me-chanically strong with porosity,but also demonstrated that the hierarchical pore structure formed during rolled-up has the potential to address the clogging problem and stimulates bone growth and repair. 展开更多
关键词 Direct ink writing(DIW) Bone repair scaffold Micro-CT bio composites
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Effectiveness of biofertilizers foliar application on yield and quality traits of flax(Linum usitatissimum L.)
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作者 Saied El Sayed A.B.Bakry +1 位作者 O.A.Nofal M.A.Abo Horish 《Oil Crop Science》 CSCD 2024年第2期91-101,共11页
Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and worldwide.Biofertilizers have a substantial impact on various metabolic processes,including increased p... Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and worldwide.Biofertilizers have a substantial impact on various metabolic processes,including increased photo-synthesis,endogenous hormone levels,ion absorption,nucleic acid synthesis,and protein synthesis.These factors collectively contribute to the growth and development of plants.Therefore,this study aims to investigate how three biofertilizers(Algae extract,CMS as a by-product of yeast,and Metalosate multi minerals as amino acids)can enhance both the quantity and quality of flax seed yield under sandy soil conditions.Two field experiments were conducted at the Experimental Station of National Research Centre in Nubaria District,Behira Governorate,Egypt during two seasons(2021/2022)using a randomized complete block design(RCBD).The results revealed significant differences among all tested biofertilizers in terms of various characteristics studied in flax.Foliar application of algae extract at a rate of 1.50 mL/L resulted in an increase in seed yield(ton/ha)by 26.69%&19.89%,straw yield(ton/ha)by 8.08%&17.12%,and oil yield(kg/ha)by 47.72%&33.69%compared to the control group during both seasons respectively.Foliar applications of algae extract at a rate of 1.50 mL/L along with CMS at a rate of 5 m L/L and amino acids at a rate of 1.50 mL/L demonstrated significantly higher macronutrient contents(N,P,K),micronutrient contents(Fe,Zn,Mn),seed oil content,and protein content in flax seeds during both seasons.The highest values for seed oil content and protein content%were obtained through foliar application of amino acids at a rate of 1.50 mL/L.It can be concluded that foliar sprays with these bio-fertilizers effectively improved flax performance by increasing seed straw and oil yields,nutrients oil,protein and fatty acids seeds contents. 展开更多
关键词 FLAX bio fertilizers Seeds yield Nutrient contents Quality
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