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Axon regeneration induced by environmental enrichment-epigenetic mechanisms 预览
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作者 Bor Luen Tang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第1期10-15,共6页
Environmental enrichment is known to be beneficial for cognitive improvement.In many animal models of neurological disorders and brain injury,EE has also demonstrated neuroprotective benefits in neurodegenerative dise... Environmental enrichment is known to be beneficial for cognitive improvement.In many animal models of neurological disorders and brain injury,EE has also demonstrated neuroprotective benefits in neurodegenerative diseases and in improving recovery after stroke or traumatic brain injury.The exact underlying mechanism for these phenomena has been unclear.Recent findings have now indicated that neuronal activity elicited by environmental enrichment induces Ca2+influx in dorsal root ganglion neurons results in lasting enhancement of CREB-binding protein-mediated histone acetylation.This,in turn,increases the expression of pro-regeneration genes and promotes axonal regeneration.This mechanism associated with neuronal activity elicited by environmental enrichment-mediated pathway is one of several epigenetic mechanisms which modulate axon regeneration upon injury that has recently come to light.The other prominent mechanisms,albeit not yet directly associated with environmental enrichment,include DNA methylation/demethylation and N6-methyladenosine modification of transcripts.In this brief review,I highlight recent work that has shed light on the epigenetic basis of environmental enrichment-based axon regeneration,and discuss the mechanism and pathways involved.I further speculate on the implications of the findings,in conjunction with the other epigenetic mechanisms,that could be harness to promote axon regeneration upon injury. 展开更多
关键词 AXON regeneration CREB-binding protein DNA methylation/demethylation dorsal root GANGLION DRG neurons environmental enrichment epigenetics histone acetylation MECHANISTIC target of rapamycin mTOR phosphatase and TENSIN HOMOLOGUE PTEN
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Effect of Al2O3/TiO2/Na2O on enrichment of phosphorus in P-bearing steelmaking slag
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作者 Kan Yu Yan-ling Zhang +1 位作者 Feng-shan Li Ming Gao 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第8期796-805,共10页
To explore the influence of Al2O3/TiO2/Na2O on the mineralogical structure and phosphorus enrichment of converter slag, phosphorus enrichment and distribution in the CaO-SiO2-Fe2O3-MgO-Al2O3/TiO2/Na2O slag system were... To explore the influence of Al2O3/TiO2/Na2O on the mineralogical structure and phosphorus enrichment of converter slag, phosphorus enrichment and distribution in the CaO-SiO2-Fe2O3-MgO-Al2O3/TiO2/Na2O slag system were experimen-tally examined. The results show that phosphorus mainly exists in an n2CaO·SiO2-3CaO·P2O5 (nC2S-C3P) solid solution. Al2O3/TiO2/Na2O is beneficial for phosphorus enrichment in the CaO-SiO2-Fe2O3-MgO slag system to various degrees. This allows screening and separation of the enriched phase in the slag. When Al2O3 content was increased from 0 to 15%, the P2O5 content in the P-rich phase increased from 13.88 to 21.32%, and the area of the P-rich phase decreased from 57.50 to 37.87%. When the TiO2 content was increased from 0 to 10%, the content of P2O5 in the P-rich phase increased from 13.88 to 22.90%, and the area of the P-rich phase decreased from 57.50 to 39.20%. When the contents of Al2O3 and TiO2 were increased, the previously formed nC2S-C3P solid solution transformed into n′C2S-C3P (n < n′) with higher phos-phorus content. Na2O had no significant effect on phosphorus enrichment, but exerted significant influence on the area of the P-rich phase. When the Na2O content was increased from 0 to 8%, the previously formed nC2S-C3P solid solution gradually became Na2Ca4(PO4)2SiO4, and the area of the P-rich phase increased from 57.50 to 68.50%. With increasing the content of ATN (a mixture with a mass ratio of Al2O3/TiO2/Na2O = 15:4:3) from 0 to 30%, the content of P2O5 increased from 13.88 to 42.10% and the area of the P-rich phase decreased from 54.92 to 18.40%. 展开更多
关键词 PHOSPHORUS ENRICHMENT nC2S-C3P solid solution Modification P-bearing STEELMAKING slag
利用流式分选技术富集空载质粒转染特定巨噬细胞的方法及条件优化 预览
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作者 吴昊 王敏 +2 位作者 罗贤强 郭建春 郑斌娇 《温州医科大学学报》 CAS 2019年第6期408-411,417共5页
目的:建立BD FACSAria II流式细胞分选仪富集PX458 空载质粒转染J774A.1 细胞的方法并进行技术优化,确立用于筛选J774A.1细胞的最佳条件。方法:构建PX458空载质粒转染J774A.1细胞株,进行7-AAD染色。选择BD FACSAria II流式细胞分选仪的1... 目的:建立BD FACSAria II流式细胞分选仪富集PX458 空载质粒转染J774A.1 细胞的方法并进行技术优化,确立用于筛选J774A.1细胞的最佳条件。方法:构建PX458空载质粒转染J774A.1细胞株,进行7-AAD染色。选择BD FACSAria II流式细胞分选仪的100 μm喷嘴以及initial、4-way purity、purity、yield、fine tune、single cell 6种分选模式分选J774A.1细胞的GFP阳性转染株,比较仪器各部分参数变化对分选效率的影响。结果:在仪器稳定的液流条件下,100 μm喷嘴各分选模式所得细胞纯度均达80%以上,其中purity模式分选效率最高,达95.7%±1.0%。结论:使用BD FACSAria II流式细胞分选仪100 μm喷嘴分选PX458空载转染的J774A.1细胞选择purity分选模式最合适。 展开更多
关键词 GFP 流式细胞术 分选模式 富集
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HPD-100大孔吸附树脂富集毛头牛蒡子中总木脂素工艺 预览
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作者 刘富铭 王东东 +1 位作者 付晓 葛亮 《化学与生物工程》 CAS 2019年第11期33-37,共5页
采用HPD 100大孔吸附树脂对毛头牛蒡子提取液中总木脂素进行富集,采用紫外可见分光光度法测定毛头牛蒡子总木脂素含量,采用HPLC法测定毛头牛蒡子牛蒡苷含量,将数据加权处理后进行综合评价,根据综合评分对树脂富集总木脂素工艺进行优化... 采用HPD 100大孔吸附树脂对毛头牛蒡子提取液中总木脂素进行富集,采用紫外可见分光光度法测定毛头牛蒡子总木脂素含量,采用HPLC法测定毛头牛蒡子牛蒡苷含量,将数据加权处理后进行综合评价,根据综合评分对树脂富集总木脂素工艺进行优化。结果表明,HPD 100大孔吸附树脂可以较好地富集毛头牛蒡子总木脂素有效成分。最佳富集工艺为:上样浓度0.20 g·mL^-1、上样流速1.5 BV·h^-1、上样量4 BV、用7 BV蒸馏水洗去杂质、再用4 BV 70%乙醇洗脱、洗脱流速1.0 BV·h^-1,富集物中总木脂素含量达到92%以上,牛蒡苷含量达到34%以上。 展开更多
关键词 毛头牛蒡子总木脂素 大孔吸附树脂 富集
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Gene set enrichment analysis of alpha-glucosidase inhibitors from Ficus benghalensis
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作者 Pukar Khanal BMPatil 《亚太热带生物医学杂志:英文版》 CAS 2019年第6期263-270,共8页
Objective:To identify alpha-glucosidase inhibitors from Ficus benghalensis and analyze gene set enrichment of regulated protein molecules.Methods:The phytoconstituents of Ficu.s benghalen.sis were queried for inhibito... Objective:To identify alpha-glucosidase inhibitors from Ficus benghalensis and analyze gene set enrichment of regulated protein molecules.Methods:The phytoconstituents of Ficu.s benghalen.sis were queried for inhibitors of alphaglucosidase,also identified as aldose reductase inhibitors.Druglikeness score,absorption,distribution,metabolism,excretion and toxicity profile,biological spectrum,and gene expression were predicated for each compound.Docking study was performed to predict the binding affinity with alpha-glucosidase and aldose reductase and compared with clinically proven molecules.Kyoto Encyclopedia of Genes and Genomes pathway analysis was performed for the regulated genes to identify the modulated pathways.Results:Apigenin,3,4’,5,7-tetrahydroxy-3’-methoxyflavone,and kaempferol were identified as inhibitors of alpha-glucosidase and aldose reductase.Kaempferol was predicted to possess the highest binding affinity with both targets.The p53 signaling pathway was predicted to modulate the majority of protein molecules in diabetes mellitus.All the alpha-glucosidase inhibitors were also predicted as membrane integrity agonist and anti-mutagenic compounds.Conclusions:The current study indicates alpha-glucosidase inhibitors from Ficus benghale,nsis can act as aldose reductase inhibitors after absorption from the intestinal tract.Furthermore,these phytoconstituents are involved in the regulation of numerous protein molecules and pathways.Hence,the anti-diabetic efficacies of these compounds are due to their action on multiple protein molecules and synergistic effects which should be confirmed by future investigations. 展开更多
关键词 FICUS benghalensis GENE SET ENRICHMENT KAEMPFEROL Network PHARMACOLOGY Type 2 diabetes mellitus
外源磷对厌氧氨氧化启动及富集的影响
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作者 傅金祥 钱杰 于鹏飞 《水处理技术》 CAS CSCD 北大核心 2019年第9期94-98,共5页
为研究外源磷对厌氧氨氧化启动及富集过程的影响,采用接种常规活性污泥进行厌氧氨氧化启动实验。结果表明,无外源磷的条件下接种普通活性污泥可以启动厌氧氨氧化并完成厌氧氨氧化菌富集,启动所需的时间相比于有外源磷的条件的时间更长,... 为研究外源磷对厌氧氨氧化启动及富集过程的影响,采用接种常规活性污泥进行厌氧氨氧化启动实验。结果表明,无外源磷的条件下接种普通活性污泥可以启动厌氧氨氧化并完成厌氧氨氧化菌富集,启动所需的时间相比于有外源磷的条件的时间更长,富集后在进水NH^+4-N、NO^-2-N的质量浓度分别为150、180 mg/L条件下,NH^+4-N和NO2--N去除率稳定在95.07%和95.97%,△ρ(NO^-2-N)/△ρ(NH^+4-N)稳定在1.2;无外源磷可缩短启动过程中的菌体自溶的时间;无外源磷条件下厌氧氨氧化启动活性提升阶段基质去除率增长较慢,培养40 d,NH^+4-N去除率由6.29%增长至34.50%。 展开更多
关键词 厌氧氨氧化 无外源磷 启动 富集
蚯蚓处理对猪粪重金属富集的影响 预览
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作者 黄炜 刁晓平 +1 位作者 李森楠 龚莹 《热带生物学报》 2019年第2期151-158,共8页
以干湿分离后的猪粪为基质,接种赤子爱胜蚓(Eisenia fetida),在室内培养4周后,利用电感耦合等离子体质谱法(ICP-MS)测定猪粪和蚯蚓体内的重金属(Cu,Zn,Cr,Pb,Cd,As)的含量,系统研究了蚯蚓作用下猪粪中重金属形态变化及蚯蚓体内重金属的... 以干湿分离后的猪粪为基质,接种赤子爱胜蚓(Eisenia fetida),在室内培养4周后,利用电感耦合等离子体质谱法(ICP-MS)测定猪粪和蚯蚓体内的重金属(Cu,Zn,Cr,Pb,Cd,As)的含量,系统研究了蚯蚓作用下猪粪中重金属形态变化及蚯蚓体内重金属的富集特征。结果表明:供试猪粪能促进蚯蚓的生长,4周后体质量明显增加,且对蚯蚓的繁殖没有影响。蚯蚓处理4周后,猪粪pH值由6.51增加至6.86。猪粪中Cu,Zn,Cr,Pb,Cd,As的总量与对照组相比,分别降低了13.69%,24.47%,30.70%,39.17%,21.91%,9.36%;同时,猪粪中Zn,Cr,Cd的残渣态比例相比对照组分别减少了15%,27%,27%。蚯蚓对重金属有一定富集作用,除Cr以外,Cu,Zn,Cd,As4种重金属在蚯蚓体内的质量含量相比实验前分别增加了0.49,3.86,0.012,0.064 mg·kg^-1,并表现出一定的时效关系,其富集系数大小顺序为Cr>Cd>Zn>Cu>As。研究表明,蚯蚓能富集猪粪中的重金属并且降低猪粪中的重金属含量,同时减少了猪粪中的部分重金属残渣态比例,有利于重金属的转移和去除。 展开更多
关键词 蚯蚓 猪粪 重金属 富集特征
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Foliar application of micronutrients enhances crop stand,yield and the biofortification essential for human health of different wheat cultivars 预览
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作者 Muhammad Zahir Aziz Muhammad Yaseen +5 位作者 Tanveer Abbas Muhammad Naveed Adnan Mustafa Yasir Hamid Qudsia Saeed XU Ming-gang 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第6期1369-1378,共10页
Globally about half of the world’s population is under micronutrient malnutrition due to poor quality food intake.To overcome this problem,fortification and biofortification techniques are often used.Biofortification... Globally about half of the world’s population is under micronutrient malnutrition due to poor quality food intake.To overcome this problem,fortification and biofortification techniques are often used.Biofortification is considered a better option than fortification due to the easy control of nutrient deficiencies present in daily food.This field experiment was conducted to evaluate the effects of foliar application of a micronutrient mixture(MNM)consisting of zinc(Zn),iron(Fe),copper(Cu),manganese(Mn)and boron(B)on yield and flour quality of wheat.The results show the effectiveness of foliar feeding for growth and yield parameters,in addition to the enriching of wheat grains with Zn,Cu,Fe,Mn and B.Compared to the control without foliar feeding,foliar application on wheat crop increased tillering ability,spike length,grain yield and the contents of Zn,Cu,Mn,Fe and B by 21,47,22,22 and 25%in wheat flour,respectively.Therefore,foliar feeding of micronutrients could be an effective approach to enrich wheat grains with essential nutrients for correcting malnutrition. 展开更多
关键词 enrichment BIOFORTIFICATION MALNUTRITION MICRONUTRIENTS wheat FLOUR
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Effect of Salinity and Potassium Enrichment on Some Growth Attributes in Sugar Beet (Beta vulgaris L.) 预览
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作者 Fadi Abbas Entessar Al-Jbawi 《农业科学与技术:B》 2019年第3期152-159,共8页
A pot experiment was conducted during winter growing season of 2014 at Homs Agriculture Research Center, General Commission for Scientific Researches (GCSAR), Syria. A factorial experiment arranged according to comple... A pot experiment was conducted during winter growing season of 2014 at Homs Agriculture Research Center, General Commission for Scientific Researches (GCSAR), Syria. A factorial experiment arranged according to complete randomized block design with six replications was used. A combination of four levels of saline irrigation water (tap water, 2,000, 4,000 and 6,000 ppm), with three K levels (180, 360 and 540 ppm), was used to evaluate the effects of saline irrigation water and K enrichment on some growth attributes of two sugar beet varieties (Semper and Alligator). Results showed that all studied growth attributes, i.e., leaf area (LA), leaf number (LN), total dry matter (TDM) and net assimilation rate (NAR) were decreased under salinity stress conditions compared to the control, while K enrichment significantly increased some of the studied characters such as LA, TDM and NAR, but the differences in LN were apparent according to increase in K levels. The variety Semper surpassed significantly the variety Alligator in LA, TDM and NAR. Results also indicated a significant interaction between salinity×potassium enrichment, varieties×potassium enrichment and salinity ? varieties. 展开更多
关键词 SALINITY POTASSIUM ENRICHMENT GROWTH traits sugar BEET (Beta VULGARIS L.)
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多重丰容对圈养小熊猫个体刻板行为的影响 预览
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作者 黄杭 林琳 +2 位作者 郑舒桓 张弥 何晓聪 《福建畜牧兽医》 2019年第3期30-34,共5页
小熊猫(Ailurus fulgens)是亚洲特有的濒危动物。由于圈养小熊猫活动空间受限、环境单调等因素,时常有刻板行为表现。本研究依据小熊猫自然行为特性及动物福利要求,以环境、食物、气味等因素进行多重丰容,观察频繁出现刻板行为的2只圈... 小熊猫(Ailurus fulgens)是亚洲特有的濒危动物。由于圈养小熊猫活动空间受限、环境单调等因素,时常有刻板行为表现。本研究依据小熊猫自然行为特性及动物福利要求,以环境、食物、气味等因素进行多重丰容,观察频繁出现刻板行为的2只圈养小熊猫个体的行为修正效果。应用聚集动物取样法,从9:00到17:00,全事件记录并观察小熊猫行为。观察发现,受试小熊猫主要表现摇晃与踱步两种刻板行为。通过丰容前与三个阶段的丰容后刻板行为发生率比较,丰容后的刻板行为均显著低于丰容前,而探究行为和修饰行为有所增加。由此可见,多重丰容可以减少圈养小熊猫刻板行为的发生,促进自然行为的表达。 展开更多
关键词 圈养小熊猫 刻板行为 丰容 动物福利
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江汉盆地潜江凹陷潜三段盐韵律层页岩油富集机理
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作者 李乐 王自翔 +4 位作者 郑有恒 陈凤玲 吴世强 漆智先 刘爱武 《地球科学》 EI CAS CSCD 北大核心 2019年第3期1012-1023,共12页
针对潜江组页岩油富集机理方面的研究较为欠缺.利用岩心图像、岩石热解、镜质体反射率、生物标志化合物、干酪根显微组分鉴定、岩石物性、测井及XPT压力试井等资料对韵律层的烃源岩品质、储集性能以及保存条件进行了综合分析.从王场背... 针对潜江组页岩油富集机理方面的研究较为欠缺.利用岩心图像、岩石热解、镜质体反射率、生物标志化合物、干酪根显微组分鉴定、岩石物性、测井及XPT压力试井等资料对韵律层的烃源岩品质、储集性能以及保存条件进行了综合分析.从王场背斜过渡至蚌湖向斜南斜坡,韵律层干酪根类型均以Ⅰ-Ⅱ1型为主,镜质体反射率介于0.51%~0.80%.王场背斜韵律层内岩石与底部盐岩内的夹层白云质泥岩间的C29甾烷成熟度指标存在明显差异,指示存在运移油.储集岩孔隙度介于7.8%~26.3%.韵律层顶底盐岩厚度大(>6m)且横向分布稳定,沉积-埋藏期并未发生严重破裂.在保存条件及储集能力优越的基础上,同层深部运移供烃是构造高部位韵律层中页岩油富集的重要因素,而原地生烃滞留则控制着构造低部位页岩油的富集. 展开更多
关键词 潜江凹陷 潜三段 盐韵律 页岩油 富集 石油地质
137Cs在我国滨海核电周边海洋生物的富集及生态风险研究 预览
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作者 纪建达 于涛 《生态毒理学报》 CAS CSCD 北大核心 2019年第1期67-74,共8页
铯-137(137Cs)是滨海核电站液态流出物中主要人工放射性核素和重要监控指标之一,易被水生生物累积,有关核电周边海域内海洋生物的核素富集状况备受关注。通过分析海洋生物富集放射性137Cs的方式、生物富集系数的种群特征、人工放射性核... 铯-137(137Cs)是滨海核电站液态流出物中主要人工放射性核素和重要监控指标之一,易被水生生物累积,有关核电周边海域内海洋生物的核素富集状况备受关注。通过分析海洋生物富集放射性137Cs的方式、生物富集系数的种群特征、人工放射性核素在生物体内的辐射剂量率状况,结果显示:1)滨海核电周边海域内137Cs的放射性水平较低;2)海洋生物对于137Cs的富集未呈现显著的种群规律;3)目前对放射性铯的富集能力较高的生物主要是底栖生物;4)核电厂周边海域内海洋生物通常未达到可导致电离辐射损伤的辐射剂量率水平。随着滨海核电在我国的大力发展,对能够快速反映环境放射性状况的指示生物的筛选、生物放射性质量安全及其生态健康风险需进一步关注。 展开更多
关键词 137Cs 海洋生物 富集 生态风险
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基于MIL-100(Fe)的磁性纳米碳材料的制备及其在内源性肽富集中的应用 预览
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作者 赵雅梦 王敏 +2 位作者 张凌怡 鲁誉浩 张维冰 《色谱》 CAS CSCD 北大核心 2019年第8期831-835,共5页
以Fe3O4为核,采用层层自组装的方法合成核壳型Fe3O4@MIL-100(Fe)磁性纳米材料,经高温煅烧得到具有较大孔径(17.78 nm)、高含碳量(6.79%)的磁性纳米材料Fe3O4@MC。将该材料用于多肽的富集,并通过基质辅助激光解吸电离飞行时间质谱仪(MALD... 以Fe3O4为核,采用层层自组装的方法合成核壳型Fe3O4@MIL-100(Fe)磁性纳米材料,经高温煅烧得到具有较大孔径(17.78 nm)、高含碳量(6.79%)的磁性纳米材料Fe3O4@MC。将该材料用于多肽的富集,并通过基质辅助激光解吸电离飞行时间质谱仪(MALDI-TOF MS)进行鉴定。Fe3O4@MC材料从牛血清白蛋白(BSA)酶解液中富集得到33条肽段,且具有较高的选择性(BSA酶解液与BSA的质量比为1∶400),用于人血清中内源性肽段的分离富集也取得了较好的效果。 展开更多
关键词 基质辅助激光解吸电离飞行时间质谱 富集 金属有机框架 内源性肽段
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活性污泥中电活性微生物的富集筛选研究进展
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作者 宋建华 杨永刚 +2 位作者 胡文哲 陈乐天 许玫英 《微生物学通报》 CAS CSCD 北大核心 2019年第8期2090-2100,共11页
活性污泥含有多种微生物,是废水处理系统中污染物降解转化的重要驱动者。电活性微生物(Electroactive microorganisms,EAMs)是活性污泥的重要微生物类群,在废水资源化与能源化中发挥着核心关键作用。本文概括了活性污泥中EAMs的富集和... 活性污泥含有多种微生物,是废水处理系统中污染物降解转化的重要驱动者。电活性微生物(Electroactive microorganisms,EAMs)是活性污泥的重要微生物类群,在废水资源化与能源化中发挥着核心关键作用。本文概括了活性污泥中EAMs的富集和筛选方法,整理总结了目前已从活性污泥中获得的EAMs菌种资源信息,在此基础上分析了从活性污泥中富集和筛选EAMs所存在的问题,并进一步展望了未来的研究方向,以期加速EAMs菌种资源的挖掘,促进以EAMs为主导的废水资源化与能源化技术发展。 展开更多
关键词 电活性微生物 活性污泥 富集 筛选 废水资源化与能源化
中华鳖器官组织对养殖环境中镉的富集 预览
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作者 刘伶俐 黄向荣 +3 位作者 黄华伟 李小玲 何志刚 李传武 《湖南农业大学学报:自然科学版》 CAS CSCD 北大核心 2019年第4期412-419,共8页
以中华鳖为试验对象,在养殖土壤中分别添加5、50和100 mg/kg的镉,以不加镉为对照,研究养殖环境中镉含量变化对中华鳖不同器官组织对镉的富集的影响,试验周期为75 d.结果表明:养殖水体、底泥及中华鳖器官组织中镉蓄积量以镉添加100 mg/k... 以中华鳖为试验对象,在养殖土壤中分别添加5、50和100 mg/kg的镉,以不加镉为对照,研究养殖环境中镉含量变化对中华鳖不同器官组织对镉的富集的影响,试验周期为75 d.结果表明:养殖水体、底泥及中华鳖器官组织中镉蓄积量以镉添加100 mg/kg的为最多,且与对照组及添加5 mg/kg组的差异具有统计学意义,存在"剂量-效应"关系;中华鳖器官组织对镉富集量从高到低依次为肝脏、肠道、裙边、肌肉,可食肌肉、裙边的镉含量均低于国家食品限量卫生标准;相关性分析显示,不同镉试验组及试验第0~30天在养殖环境及各组织间的镉含量均呈显著正相关,存在"时间-效应"关系,而养殖环境与被测组织的镉含量相关性不显著,甚至对照组的底泥和裙边与肝脏间、50 mg/kg组的水体与肝脏和肠道间、100 mg/kg组的水体与肝脏间均呈负相关;随着环境中镉的迁移转化及器官组织的消除代谢,试验第45天的水体和肠道分别与肌肉和裙边间,试验第60天的肠道与各养殖环境因素和各器官组织间、肌肉与水体和裙边及肝脏间,试验第75天的水体和裙边分别与肠道和肝脏间、肠道与底泥和肌肉间的相关性均不显著. 展开更多
关键词 中华鳖 富集 迁移 转化 代谢
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复合污染土壤上几种叶类蔬菜对Cd和As的富集效应 预览
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作者 孟媛 张亮 +4 位作者 王林权 上官宇先 杨阳 李雪芳 李娜 《植物营养与肥料学报》 CAS CSCD 北大核心 2019年第6期972-981,共10页
[目的]不同蔬菜镉、砷富集系数各异,对镉和砷污染土壤的响应也不同。研究复合污染土壤上不同叶类蔬菜对Cd和As的积累效应,为轻度中度Cd和As污染土壤的合理与安全利用提供适宜的蔬菜种类。[方法]采集了西安市12个污染程度不同的菜地耕层... [目的]不同蔬菜镉、砷富集系数各异,对镉和砷污染土壤的响应也不同。研究复合污染土壤上不同叶类蔬菜对Cd和As的积累效应,为轻度中度Cd和As污染土壤的合理与安全利用提供适宜的蔬菜种类。[方法]采集了西安市12个污染程度不同的菜地耕层土壤,于2015年3月6日5月26日在西北农林科技大学资源环境学院遮雨大棚内进行了盆栽试验。供试7种叶菜,包括菠菜、油菜、生菜、油麦菜、苋菜、空心菜和茼蒿。蔬菜收获后,测量了蔬菜产量、Cd和As含量与吸收累积量,计算了蔬菜对Cd和As的富集系数等,并用线性回归模型研究了不同蔬菜栽培的土壤Cd和As安全临界值。[结果]镉污染土壤(0.6~2.4 mg/kg)对大多数蔬菜生物量有抑制效应,中、低浓度镉砷复合污染(Cd 1.0~2.4 mg/kg,As 24.9~26.8 mg/kg)对供试蔬菜生长没有叠加效应。镉污染土壤上,菠菜、油菜、苋菜叶、生菜可食部Cd含量均超出食品安全限量标准(0.2 mg/kg),其中菠菜和油菜Cd最高超标4倍以上;而茼蒿和空心菜茎秆Cd未超标。虽然供试蔬菜砷含量随着土壤砷含量增加有升高趋势,但叶菜As含量没有超标。7种蔬菜Cd富集系数为0.083~0.491,高低顺序为油菜、菠菜、生菜和苋菜叶>油麦菜、苋菜茎和空心菜叶>空心菜茎和茼蒿。菠菜、油菜、生菜、油麦菜、苋菜、空心菜和茼蒿土壤Cd安全临界值分别为0.33、0.38、0.46、1.15、0.59~1.79、1.49~8.16和8.98~17.11 mg/kg,其中菠菜、油菜和生菜阈值与现行标准(0.3~0.6 mg/kg)相当,而油麦菜、苋菜、空心菜和茼蒿均大于土壤重金属污染限量值。As富集系数为0.002~0.006,空心菜叶和茼蒿叶片As富集系数显著高于其他蔬菜。7种蔬菜的土壤As临界阈值分别为62.31、70.35、70.21、67.41、67.86~90.43、57.21~75.70和72.43~105.06 mg/kg,均高于现行标准(25 mg/kg)。[结论]中等程度的Cd和As复合污染土壤上,Cd对蔬菜的生长有显著的抑制,As� 展开更多
关键词 富集系数 土壤阈值 菠菜 茼蒿
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分子蒸馏富集亚麻籽油中α-亚麻酸的研究 预览
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作者 刘金菊 杨震发 +1 位作者 白巧霞 杨顺义 《甘肃农业科技》 2019年第5期16-21,共6页
亚麻籽油经甲酯化后,采用分子蒸馏技术对其中α-亚麻酸进行分离纯化,以α-亚麻酸质量分数和提取率作为衡量纯化效果的指标。经单因素试验确定蒸馏温度、蒸馏压力、进料速度、刮膜转速的操作范围,并利用响应曲面法Box-Behnken试验设计,... 亚麻籽油经甲酯化后,采用分子蒸馏技术对其中α-亚麻酸进行分离纯化,以α-亚麻酸质量分数和提取率作为衡量纯化效果的指标。经单因素试验确定蒸馏温度、蒸馏压力、进料速度、刮膜转速的操作范围,并利用响应曲面法Box-Behnken试验设计,确定了亚麻籽油中α-亚麻酸分离纯化的工艺条件,即蒸馏温度90℃、蒸馏压力0.8Pa、进料速度0.87mL/min、刮膜转速287r/min。在该工艺条件下,得到α-亚麻酸含量为81.15%,提取率为78.20%。 展开更多
关键词 亚麻籽油 Α-亚麻酸 响应曲面法 分子蒸馏 富集
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印度洋钙质软泥和硅质软泥稀土元素组成和富集机制 预览
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作者 刘明 孙晓霞 +3 位作者 石学法 张文强 范德江 杨作升 《海洋学报》 CAS CSCD 北大核心 2019年第1期58-71,共14页
本文针对采自印度洋深海中最常见的两类生物成因沉积物——钙质软泥和硅质软泥,开展了全岩样和不同粒级组分中常微量元素、稀土元素和Y(REY)含量的系统分析,探讨了两类沉积物中REY的组成特征、物质来源和富集机制。研究表明,钙质软泥以... 本文针对采自印度洋深海中最常见的两类生物成因沉积物——钙质软泥和硅质软泥,开展了全岩样和不同粒级组分中常微量元素、稀土元素和Y(REY)含量的系统分析,探讨了两类沉积物中REY的组成特征、物质来源和富集机制。研究表明,钙质软泥以富含CaO和Sr为主要特征,硅质软泥则富集SiO2、Al2O3、Fe2O3等。钙质软泥中ΣREY平均含量为40.56×10-6,轻稀土元素(LREE)略有富集,REY有向细粒沉积物中富集的特征,PAAS标准化后全岩样和不同粒级组分均表现为Ce负异常、Eu和Y正异常;REY以自生来源为主,继承了海水的组成特征,同时也受到了热液流体物质和洋底玄武岩风化产物的影响。硅质软泥中ΣREY的含量为248.54×10^-6,LREE相对富集,REY在4Φ以细的沉积物中富集;研究站位沉积物中ΣREY含量处于边界品位附近,但在细粒级沉积物中重稀土元素(HREY)含量则达到了工业品位;该类沉积物细粒组分中REY主要来自陆源或火山碎屑组分中黏土矿物和铁锰氧化物吸附作用,粗粒组分中REY来源则主要与生物作用相关;硅质软泥中REY的富集与沉积物中磷灰石等矿物相关,部分不同来源的REY可能是在沉积之后的成岩过程中再次分配向磷灰石、钙十字沸石等矿物中富集。 展开更多
关键词 印度洋 钙质软泥 硅质软泥 稀土元素 富集规律
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Sources and Ecological Risks of Heavy Metals in Soils Under Different Land Uses in Bangladesh
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作者 Mohammad Saiful ISLAM Mohammad Kawser AHMED +1 位作者 Mohammad Habibullah AL-MAMUN Shah Mohammad Asraful ISLAM 《土壤圈:英文版》 SCIE CAS CSCD 2019年第5期665-675,共11页
Soil heavy metal pollution, influenced by both natural and anthropogenic factors, significantly reduces environmental quality. In this study, Cr, Ni, Cu, As, Cd, and Pb in eight different land-use soils from Patuakhal... Soil heavy metal pollution, influenced by both natural and anthropogenic factors, significantly reduces environmental quality. In this study, Cr, Ni, Cu, As, Cd, and Pb in eight different land-use soils from Patuakhali District in Bangladesh were assessed. Concentrations of Cr, Ni, Cu, As, Cd, and Pb in soils were 1-87, 5-271, 4-181, 0-80, 0.2-24.0, and 5-276 mg kg-1, respectively, measured using an inductively coupled plasma-mass spectrometer. The enrichment factor, pollution load index (PLI), and contamination factor (CJ) of metal i were used to assess the ecological risk posed by metals in soils. The PLI ranged from 0.78 to 2.66, indicating baseline levels to progressive deterioration of soil due to metal contamination. However, C;of Cd ranged from 1.8 to 12.0, which showed that the studied soils were strongly impacted by Cd. Considering the severity of the potential ecological risk of a single metal, the descending order was Cd > As > Pb > Cu > Ni > Cr. Soils under all land uses showed moderate to very high potential ecological risk. 展开更多
关键词 Cd CONTAMINATION FACTOR degree of CONTAMINATION enrichment FACTOR environmental quality POLLUTION load index SOIL DETERIORATION SOIL POLLUTION
Influence of depositional environment on coalbed methane accumulation in the Carboniferous-Permian coal of the Qinshui Basin, northern China
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作者 Haihai HOU Longyi SHAO +3 位作者 Shuai WANG Zhenghui XIAO Xuetian WANG Zhen LI 《地球科学前沿:英文版》 CSCD 2019年第3期535-550,共16页
Based on analyses of the lithofacies palaeo-geography of the Taiyuan and the Shanxi Formations in the Qinshui Basin, the spatial variations of the coal seam thickness, coal maceral composition, coal quality, and gas c... Based on analyses of the lithofacies palaeo-geography of the Taiyuan and the Shanxi Formations in the Qinshui Basin, the spatial variations of the coal seam thickness, coal maceral composition, coal quality, and gas content, together with the lithofacies of the surrounding rocks in each palaeogeographic unit were investigated. The results show that the thick coals of the Taiyuan Formation are mainly distributed in delta and barrier island depositional units in the Yangquan area in the northern part of the basin and the Zhangzi area in the southeastern part of the basin. The thick coals of the Shanxi Formation are located within transitional areas between delta plain and delta front depositional units in the central southern part of the basin. The Taiyuan Formation generally includes mudstone in its lower part, thick, continuous coal seams and limestones in its middle part, and thin, discontinuous coal seams and limestone and sand-mud interbeds in its top part. The Shanxi Formation consists of thick, continuous sandstones in its lower part, thick coal seams in its middle part, and thin coal seams, sandstone, and thick mudstone in its upper part. From the perspective of coal-bearing sedimentology and coalbed methane (CBM) geology, the lithology and thickness of the surrounding rocks of coal seams play more significant roles in controlling gas content variation than other factors such as coal thickness, coal macerals, and coal quality. Furthermore, it is found that the key factors influencing the gas content variation are the thicknesses of mudstone and limestone overlying a coal seam. At similar burial depths, the gas content of the Taiyuan coal seams decreases gradually in the lower delta plain, barrier-lagoon,delta front, barrier-tidal flat, and carbonate platform depositional units. The CBM enrichment areas tend to be located in zones of poorly developed limestone and well-developed mudstone. In addition, the gas content of the Shanxi Formation is higher in the coals of the delta front facies compared to those i 展开更多
关键词 DEPOSITIONAL environment coalbed methane ENRICHMENT condition gas content Taiyuan FORMATION Shanxi FORMATION
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