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温度对于大豆分离蛋白起泡性的影响研究 被引量:33
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作者 李维瑶 何志勇 +2 位作者 熊幼翎 黄小林 陈洁 《食品工业科技》 CAS CSCD 北大核心 2010年第2期86-88,共3页
研究了20~90℃下商业用大豆分离蛋白(SPI)的起泡性。随着溶解温度的升高,5%大豆分离蛋白的溶解性及疏水性逐渐提高,起泡能力逐渐增强,泡沫稳定性则逐渐下降;将不同温度下5%大豆分离蛋白中的可溶性蛋白采用离心方法分离后发现可溶性蛋... 研究了20~90℃下商业用大豆分离蛋白(SPI)的起泡性。随着溶解温度的升高,5%大豆分离蛋白的溶解性及疏水性逐渐提高,起泡能力逐渐增强,泡沫稳定性则逐渐下降;将不同温度下5%大豆分离蛋白中的可溶性蛋白采用离心方法分离后发现可溶性蛋白的起泡性表现出与5%大豆分离蛋白相反的趋势,尤其在20~40℃的溶解温度下可溶性蛋白的起泡性远远优于大豆分离蛋白的起泡性。研究结果也说明,溶液中高比例可溶性大豆蛋白的存在可能有利于蛋白质泡沫的形成,但不能对泡沫的稳定性起到良好的支撑作用,同时大豆蛋白在溶液中的构象也会影响其起泡性。 展开更多
关键词 大豆分离蛋白 可溶性蛋白 起泡性
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Effectiveness of fluidized pellet bed for removing soluble contaminants 被引量:7
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作者 WANG Xiaochang,LI Zhihua,WANG Zhen,LI Jinrong,LI Jiayu,CHEN Rong Key Laboratory of Northwest Water Resource,Environment and Ecology,MOE,Xi’an University of Architecture and Technology,Xi’an 710055,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第1期13-17,共5页
Fluidized pellet bed (FPB) has been successfully applied in water and wastewater treatment. However, the removal mechanism of contaminants especially the soluble ones, is still unclear. This study aimed to evaluate ... Fluidized pellet bed (FPB) has been successfully applied in water and wastewater treatment. However, the removal mechanism of contaminants especially the soluble ones, is still unclear. This study aimed to evaluate the effectiveness of FPB reactor for removing soluble contaminants from synthetic wastewater. By only coagulation through jar test operation with addition of polyaluminium chloride (PAC1) as primary coagulant and polyacryamide (PAM) as coagulant-aid, the removals of soluble chemical oxygen demand (COD), total phosphorus (TP), and NH4^+-N were found to be only 2.2%-7.5%, 5.7%-25.5%, and 9.9%-18.5%, respectively. However, by FPB operation under the same dosage of coagulants, these values increased to 82.7%, 37.2%, and 50%, indicating that the formation of pellets in the FPB effectively enhanced the removal of soluble contaminants. By careful comparison of the settleablility and filterability of the pollutants after coagulation, the originally soluble contaminants could be divided into three groups, namely: (1) coagulated-and- settleable, (2) coagulated-but-nonsettleable, and (3) uncoagulable. It was found that not only the first two groups but also a large part of the third group could be effectively removed by FPB operation. However, the mechanism for the removal of the uncoagulable pollutants by FPB operation still needs further investigation. 展开更多
关键词 fluidized pellet bed COAGULATION soluble contaminants fraction
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GC/MS Analysis of Organic Compounds in Hot Water-Extractable Fraction from Shenfu Coal 被引量:7
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作者 LI Bao-min YUAN Cheng ZONG Zhi-min CAO Jing-pei LIU Guang-feng WEI Xian-yong 《Journal of China University of Mining and Technology》 EI 2007年第3期354-357,共4页
Shenfu Coal was extracted with hot pure water and slurry was isolated. The concentrated benzene-soluble fraction (CBSF) was analyzed with GC/MS and four types of organic compounds (OCs) were detected: HACOCs,DTEs,DMDT... Shenfu Coal was extracted with hot pure water and slurry was isolated. The concentrated benzene-soluble fraction (CBSF) was analyzed with GC/MS and four types of organic compounds (OCs) were detected: HACOCs,DTEs,DMDT and LCAs. The amount of benzyl benzoate which is the most abundant OC was calculated by an inter-nal standard method with an indicated amount of BP. The broken hydrogen bonds and ether bonds were responsible for the extraction of OCs from the coal .DTEs,DMDT and LCAs are essentially insoluble in water,whereas they are soluble,probably owing to intermolecular interaction of OCs with HACOCs. 展开更多
关键词 thermal extraction GC/MS analysis water-soluble fraction benzene-soluble fraction
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Cytotoxicity of the soluble and insoluble fractions of atmospheric fine particulate matter 被引量:5
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作者 Ling Liu Qiuhua Zhou +4 位作者 Xuezhi Yang Gang Li Jingzhu Zhang Xuehua Zhou Wei Jiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第5期105-116,共12页
Inhaled atmospheric fine particulate matter(PM2.5)includes soluble and insoluble fractions,and each fraction can interact with cells and cause adverse effects.PM2.5 samples were collected in Jinan,China,and the solubl... Inhaled atmospheric fine particulate matter(PM2.5)includes soluble and insoluble fractions,and each fraction can interact with cells and cause adverse effects.PM2.5 samples were collected in Jinan,China,and the soluble and insoluble fractions were separated.According to physiochemical characterization,the soluble fraction mainly contains watersoluble ions and organic acids,and the insoluble fraction mainly contains kaolinite,calcium carbonate and some organic carbon.The interaction between PM2.5 and model cell membranes was examined with a quartz crystal microbalance with dissipation(QCM-D)to quantify PM2.5 attachment on membranes and membrane disruption.The cytotoxicity of the total PM2.5 and the soluble and insoluble fractions,was investigated.Negatively charged PM2.5 can adhere to the positively charged membranes and disrupt them.PM2.5also adheres to negatively charged membranes but does not cause membrane rupture.Therefore,electrostatic repulsion does not prevent PM2.5 attachment,but electrostatic attraction induces remarkable membrane rupture.The human lung epithelial cell line A549 was used for cytotoxicity assessment.The detected membrane leakage,cellular swelling and blebbing indicated a cell necrosis process.Moreover,the insoluble PM2.5 fraction caused a higher cell mortality and more serious cell membrane damage than the soluble fraction.The levels of reactive oxygen species(ROS)enhanced by the two fractions were not significantly different.The findings provide more information to better understand the mechanism of PM2.5 cytotoxicity and the effect of PM2.5 solubility on cytotoxicity. 展开更多
关键词 PM2.5 soluble fraction Insoluble fraction Membrane rupture Reactive oxygen species
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Antimicrobial activities of the rhizome extract of Zingiber zerumbet Linn 被引量:4
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作者 Golam Kader Farjana Nikkon +1 位作者 Mohammad Abdur Rashid Tanzima Yeasmin 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第5期409-412,共4页
Objective:To investigate antimicrobial effects of ethanolic extract of Zingiber zerumbet(Z.zerumbet)(L.)Smith and its chloroform and petroleum ether soluble fractions against pathogenic bacteria and fungi.Methods:The ... Objective:To investigate antimicrobial effects of ethanolic extract of Zingiber zerumbet(Z.zerumbet)(L.)Smith and its chloroform and petroleum ether soluble fractions against pathogenic bacteria and fungi.Methods:The fresh rhizomes of Zingiber zerumbet were extracted in cold with ethanol(4.0 L)after concentration.The crude ethanol extract was fractionated by petroleum ether and chloroform to form a suspension of ethanol extract(15.0 g),petroleum ether fraction(6.6 g)and chloroform soluble fraction(5.0 g).The crude ethanol extract and its petroleum ether and chloroform fractions were evaluated for antibacterial and antifungal activity against thirteen pathogenic bacteria and three fungi by the disc diffusion method.Commercially available kanamycin(30μg/disc)was used as standard disc and blank discs impregnated with the respective solvents were used as negative control.Results:At a concentration of 400μg/disc,all the samples showed mild to moderate antibacterial and antifungal activity and produced the zone of inhibition ranging from 6 mm to 10 mm.Among the tested samples,the crude ethanol extract showed the highest activity against Vibrio parahemolyticus(V.parahemolyticus).The minimum inhibitory concentration(MIC)of the crude ethanol extract and its fractions were within the value of 128-256μg/mL against two Gram positive and four Gram negative bacteria and all the samples showed the lowest MIC value against V.parahemolyticus(128μg/mL).Conclusions:It can be concluded that,potent antibacterial and antifungal phytochemicals are present in ethanol extract of Z.zerumbet(L.). 展开更多
关键词 Zingiberzerumbet(L.) Smith Antibacterial ANTIFUNGAL Minimum inhibitory concentration(MIC) Antimicrobial ACTIVITY RHIZOME ANTIFUNGAL ACTIVITY PHYTOCHEMICALS Disc diffusion method soluble fraction PATHOGENIC bacteria
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Cd胁迫下不同水稻品种组织细胞中Cd的转运分配研究 被引量:5
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作者 唐杰 徐强 +7 位作者 王昌全 曾建 李冰 张中伟 李一丁 吕政 何玉亭 周泽弘 《生态环境学报》 CSCD 北大核心 2016年第12期2014-2020,共7页
采用土培试验,以越冬稻、R1088(籽粒Cd低积累)和IR34582、太粳558(籽粒Cd高积累)4个水稻品种为试验材料,研究不同水稻品种在Cd0(不加Cd)、Cd5(5 mg·kg^(-1))和Cd25(25 mg·kg^(-1))胁迫下对Cd的吸收、转运及其分配特征,以期为... 采用土培试验,以越冬稻、R1088(籽粒Cd低积累)和IR34582、太粳558(籽粒Cd高积累)4个水稻品种为试验材料,研究不同水稻品种在Cd0(不加Cd)、Cd5(5 mg·kg^(-1))和Cd25(25 mg·kg^(-1))胁迫下对Cd的吸收、转运及其分配特征,以期为培育镉低积累水稻品种提供科学依据。结果表明,(1)Cd胁迫下,Cd低积累水稻品种根Cd含量显著高于Cd高积累水稻品种,而地上部Cd含量却显著低于Cd高积累水稻品种;同时,其TF_(根-茎)和TF_(茎-叶鞆)也显著低于Cd高积累水稻品种。(2)Cd在各组织亚细胞中的含量表现为细胞壁>可溶部分>细胞膜>细胞器。Cd胁迫下,Cd低积累水稻品种根系细胞壁(F1)、细胞器(F2)、细胞膜(F3)和可溶部分(F4)Cd含量均显著高于Cd高积累水稻品种,而茎、叶鞘和叶中F1、F2、F3和F4Cd含量却显著低于Cd高积累水稻品种。(3)不同水稻品种各组织间转移系数与根系Cd亚细胞分布比例相关性分析表明,Cd5处理中,TF_(根-茎)分别与F1和F4分配比例呈极显著负相关和显著正相关,相关系数分别为-0.93 1(P<0.01)和0.702(P<0.05);Cd25处理中,TF_(根-茎)与F1和F4分配比例呈极显著负相关和极显著正相关,相关系数分别为-0.908和0.786(P<0.01)。综上所述,Cd胁迫下水稻各组织Cd含量显著增加,且Cd含量和TF_(根-茎)在Cd高低积累水稻品种间存在显著差异,根系细胞壁和可溶部分在Cd从根部向上转运的过程中起着重要作用。 展开更多
关键词 水稻 CD胁迫 亚细胞分布 细胞壁 可溶部分
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灌浆期镉胁迫下水稻Cd在组织细胞中的特征研究 被引量:3
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作者 唐杰 徐强 +6 位作者 罗成 王昌全 李冰 曾建 张中伟 吕政 付铄岚 《环境科学与技术》 CAS CSCD 北大核心 2017年第S1期49-55,共7页
土培试验,以籽粒Cd低积累水稻品种(越冬稻和R1088)和籽粒Cd高积累水稻品种(IR34582和太粳558)为试验材料,研究灌浆期水稻在Cd0(不加Cd)、Cd5(5 mg/kg)和Cd25(25 mg/kg)胁迫下Cd在其组织细胞中的特征,为培育Cd低积累水稻品种以及一定程... 土培试验,以籽粒Cd低积累水稻品种(越冬稻和R1088)和籽粒Cd高积累水稻品种(IR34582和太粳558)为试验材料,研究灌浆期水稻在Cd0(不加Cd)、Cd5(5 mg/kg)和Cd25(25 mg/kg)胁迫下Cd在其组织细胞中的特征,为培育Cd低积累水稻品种以及一定程度Cd污染农田的水稻安全生产提供科学依据。结果表明:(1)水稻各组织部位Cd含量均随Cd处理浓度的增加而增加,各组织部位Cd含量依次为根系﹥茎﹥叶鞘﹥叶﹥籽粒。(2)Cd胁迫下,Cd低积累品种越冬稻和R1088根细胞壁(F1)、细胞器(F2)、细胞膜(F3)和可溶部分(F4)Cd含量显著高于Cd高积累品种IR34582和太粳558,而茎、叶鞘和叶F1、F2、F3和F4 Cd含量却显著低于Cd高积累品种IR34582和太粳558。(3)Cd胁迫为Cd5时,TF_(根-茎)和TF_(茎-籽粒)分别均与F1和F4分配比例成极显著负相关和极显著正相关,相关系数分别为-0.947、-0.966和0.884、0.965(p<0.01);而在Cd胁迫为Cd25时,TF_(根-茎)和TF_(茎-籽粒)与F1和F4分配比例也成极显著负相关和极显著正相关,相关系数分别为-0.786、-0.936和0.865、0.936(p<0.01)。综上所述,Cd胁迫下水稻各组织Cd含量显著增加,且Cd含量、TF_(根-茎)、TF_(茎-籽粒)、TF_(叶鞘-籽粒)和TF_(叶-籽粒)在Cd高低积累水稻品种间存在显著差异,根和茎中细胞壁、可溶部分在Cd从根部向上及从茎向籽粒转运过程中起着重要作用。 展开更多
关键词 水稻 CD胁迫 组织细胞 细胞壁 可溶部分
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Decomposition and Products of Wheat and Rice Straw from a FACE Experiment Under Flooded Conditions 被引量:3
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作者 LIU Juan HAN Yong CAI Zu-Cong 《Pedosphere》 SCIE CAS CSCD 2009年第3期389-397,共9页
Winter wheat and rice straw produced under ambient and elevated CO2 in a China rice-wheat rotation free-air CO2 enrichment (FACE) experiment was mixed with a paddy soil at a rate of 10 g kg^-1 (air-dried), and the... Winter wheat and rice straw produced under ambient and elevated CO2 in a China rice-wheat rotation free-air CO2 enrichment (FACE) experiment was mixed with a paddy soil at a rate of 10 g kg^-1 (air-dried), and the mixture was incubated under flooded conditions at 25℃ to examine the differences in decomposition as well as the products of crop residues produced under elevated CO2. Results showed that the C/N ratio and the amount of soluble fraction in the amended rice straw grown under elevated CO2 (FR) were 9.8% and 73.1% greater, and the cellulose and lignin were 16.0% and 9.9% lesser than those of the amended rice straw grown under ambient CO2 (AR), respectively. Compared with those of the AR treatment, the CO2-C and CH4-C emissions in the FR treatment for 25 d were increased by 7.9% and 25.0%, respectively; a higher ratio of CH4 to CO2 emissions induced by straw in the FR treatment was also observed. In contrast, in the treatments with winter wheat straw, the CO2-C and CH4-C emissions, the ratio of straw-induced CH4 to CO2 emissions, and the straw composition were not significantly affected by elevated CO2, except for an 8.0% decrease in total N and a 9.7% increase in C/N ratio in the wheat straw grown under elevated CO2. Correlation analysis showed that the net CO2-C and CH4-C emission from straw and the ratio of straw-induced CH4 to CO2 emissions were all exponentially related to the amount of soluble fraction in the amended straw (P 〈0.05). These indicated that under flooded conditions, the turnover and CH4 emission from crop straw incorporated into soil were dependent on the effect of elevated CO2 on straw composition, and varied with crop species. Incorporation of rice straw grown under elevated CO2 would stimulate CH4 emission from flooded rice fields, whereas winter wheat straw grown under elevated CO2 had no effect on CH4 emission. 展开更多
关键词 carbon cycle CH4 CO2 emissions soluble fraction
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Soil Aggregates, Organic Matter, and Labile C and N Fractions after 37 Years of N, P and K Applications to an Irrigated Subtropical Soil under Maize-Wheat Rotation 被引量:3
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作者 S. Kumar M. S. Aulakh A. K. Garg 《Journal of Agricultural Science and Technology(A)》 2011年第2X期170-181,共12页
Abstract: Physical, chemical and biological soil properties in surface (0-5 cm) and subsurface soil (5-15 cm) were determined in a field experiment conducted with seven treatments consisted of different combinati... Abstract: Physical, chemical and biological soil properties in surface (0-5 cm) and subsurface soil (5-15 cm) were determined in a field experiment conducted with seven treatments consisted of different combinations of fertilizer N (0, 100 and 200 kg N ha^-1), P (0, 22 and 44 kg P2O5 ha^-1) and K (0, 41 and 82 kg K2O ha^-1) applied both to summer-grown maize (Zea mays L.) and winter-grown wheat (Triticum aestivum L.) crops continuously for 37 years under irrigated subtropical conditions. Application of N, P and K significantly increased water stable aggregates and had profound effects in increasing the mean weight diameter as well as the formation of macro-aggregates, which were highest in both surface (81%) and subsurface (74%) soil layers with application of 100 kg N + 22 kg P2O5 + 41 kg K2O ha^-1 (N100P22K41). The N100P22K41 treatment also enhanced total organic C (TOC) from 4.4 g kg^-1 in no-NPK control to 4.8 g kg^-1in surface layer and from 3.3 to 4.1 g kg1 in subsurface layer leading to the 20% higher TOC stocks in 0-15 cm soil. The labile C and N fractions such as water soluble C, particulate and light fraction organic matter, potentially mineralizable N and microbial biomass were also highest under the optimized balanced application of N100P22K41. Relatively higher increase in all labile fractions of C and N as proportion of TOC and total N, respectively suggested that these are potential indicators to reflect changes in management practices long before changes in TOC and TN are detectable. These results demonstrated that optimized balanced application of N, P and K is crucial for improving soil health ensuring long-term sustainability of farming systems in semiarid subtropical soils. 展开更多
关键词 Total organic C water stable aggregate water soluble C particulate and light fraction organic matter potentiallymineralizable N microbial biomass C and N soil health.
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经ZrO_2/SO_4^(2-)催化所得萘齐聚物的中间相转化行为 被引量:3
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作者 胡子君 吕春祥 +3 位作者 凌立成 刘朗 张碧江 钱树安 《燃料化学学报》 EI CAS CSCD 北大核心 1997年第6期554-559,共6页
本文探讨了模型化合物萘在ZrO2/SO24固体超强酸催化剂作用下制备出富含环烷结构的萘齐聚物,由此产物经过简单热解制备中间相沥青的研究。着重从中间相沥青在有机溶剂中的溶解度观点出发,并结合软化点、各向异性含量、H/C... 本文探讨了模型化合物萘在ZrO2/SO24固体超强酸催化剂作用下制备出富含环烷结构的萘齐聚物,由此产物经过简单热解制备中间相沥青的研究。着重从中间相沥青在有机溶剂中的溶解度观点出发,并结合软化点、各向异性含量、H/C原子比等参数,探讨了制备条件对最终产物性质的影响。实验结果表明,族组成中各组分适当比例的搭配是形成优质中间相沥青的必要条件。 展开更多
关键词 萘齐聚物 固体超强酸 沥青
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Increased Soluble Epoxide Hydrolase Activity Positively Correlates with Mortality in Heart Failure Patients with Preserved Ejection Fraction:Evidence from Metabolomics 被引量:1
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作者 Liyuan Peng Ziping Song +13 位作者 Chengcheng Zhao Kudusi Abuduwufuer Yanwen Wang Zheng Wen Li Ni Chenze Li Ying Yu Yi Zhu Hualiang Jiang Jinshan Shen Xiangrui Jiang Chen Chen Xu Zhang Dao Wen Wang 《Phenomics》 2023年第1期34-49,共16页
Epoxyeicosatrienoic acids(EETs)have pleiotropic endogenous cardiovascular protective effects and can be hydrolyzed to the corresponding dihydroxyeicosatrienoic acids by soluble epoxide hydrolase(sEH).Heart failure wit... Epoxyeicosatrienoic acids(EETs)have pleiotropic endogenous cardiovascular protective effects and can be hydrolyzed to the corresponding dihydroxyeicosatrienoic acids by soluble epoxide hydrolase(sEH).Heart failure with preserved ejection fraction(HFpEF)has shown an increased prevalence and worse prognosis over the decades.However,the role of sEH activ-ity in HFpEF remains unclear.We enrolled 500 patients with HFpEF and 500 healthy controls between February 2010 and March 2016.Eight types of sEH-related eicosanoids were measured according to target metabolomics,and their correlation with clinical endpoints was also analyzed.The primary endpoint was cardiac mortality,and the secondary endpoint was a composite of cardiac events,including heart failure(HF)readmission,cardiogenic hospitalization,and all-cause mortal-ity.Furthermore,the effect of sEH inhibitors on cardiac diastolic function in HFpEF was investigated in vivo and in vitro.Patients with HFpEF showed significantly enhanced EET degradation by the sEH enzyme compared with healthy controls.More importantly,sEH activity was positively correlated with cardiac mortality in patients with HFpEF,especially in older patients with arrhythmia.A consistent result was obtained in the multiple adjusted models.Decreased sEH activity by the sEH inhibitor showed a significant effective effect on the improvement of cardiac diastolic function by ameliorating lipid disorders in cardiomyocytes of HFpEF mouse model.This study demonstrated that increased sEH activity was associated with cardiac mortality in patients with HFpEF and suggested that sEH inhibition could be a promising therapeutic strategy to improve diastolic cardiac function.Clinical trial identifier:NCT03461107(https://clini caltr ials.gov). 展开更多
关键词 soluble epoxide hydrolase Heart failure with preserved ejection fraction EICOSANOIDS Epoxyeicosatrienoic acids
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Subcellular Distribution of Calcium, Magnesium and Iron in Brassica napus Leaves during Cold Acclimatization 被引量:2
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作者 张树杰 张春雷 《Agricultural Science & Technology》 CAS 2012年第2期310-314,369,共6页
[Objective] The aim of the present study was to investigate the characteristics of calcium (Ca), magnesium (Mg) and iron (Fe) subcellular distributions in oilseed rape (Brassica napus L.) leaves during cold ac... [Objective] The aim of the present study was to investigate the characteristics of calcium (Ca), magnesium (Mg) and iron (Fe) subcellular distributions in oilseed rape (Brassica napus L.) leaves during cold acclimatization. [Method] A field experiment was conducted at two contrasting environments with three replicates and included a freezing sensitive variety (cv. Zhongshuang No. 11, ZS) and a freezing tolerant variety (cv. Ganyouza No. 1, GY). [Result] The concentrations of Ca, Mg and Fe were significantly increased in plants roots, and the concentrations of Ca and Mg were significantly decreased but the Fe concentration was significantly increased in plants shoots. In leaves, the Ca concentration stored in soluble fraction was significantly increased and the Ca concentration of organelle-contained fraction and cell wall-associated fraction were significantly decreased with experiment time. The Mg concentrations stored in soluble fraction, organelle-contained fraction and cell wall-associated fraction were decreased with time. In contrary, the Fe concentration stored in soluble fraction, organelle-contained fraction and cell wall associated-fraction was significantly increased with time. Meanwhile, the changes of these measures of ZS were much higher than those of GY during cold acclimatization, which might be due to the GY is a freezing tolerant variety but ZS is not. [Conclusion] These results suggested that increasing the concentrations of Ca, Mg and Fe in plants shoots might increase the cold resistance of oilseed rape. 展开更多
关键词 Cell wall FERRITIN Field experiment ORGANELLE soluble fraction
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桉木屑在离子液体[C_4H_8SO_3 Hmim]HSO_4催化下液化行为研究 被引量:1
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作者 吴鸿楼 谌凡更 王静 《林产化学与工业》 EI CAS CSCD 北大核心 2017年第2期42-48,共7页
以乙二醇为溶剂,在1-磺酸丁基-3-甲基咪唑硫酸氢盐([C_4H_8SO_3 Hmim]HSO_4)酸性离子液体催化下,进行桉木屑的液化反应。考察了反应温度、反应时间、催化剂用量对液化率以及产物分布的影响,并对液化产物进行了表征。结果表明:在最优液... 以乙二醇为溶剂,在1-磺酸丁基-3-甲基咪唑硫酸氢盐([C_4H_8SO_3 Hmim]HSO_4)酸性离子液体催化下,进行桉木屑的液化反应。考察了反应温度、反应时间、催化剂用量对液化率以及产物分布的影响,并对液化产物进行了表征。结果表明:在最优液化条件10 g桉木屑,60 g乙二醇,[C_4H_8SO_3 Hmim]HSO_4用量为10 mmol,液化温度为160℃,液化时间150 min下,桉木屑的液化率最高可达96.41%。在离子液体催化下,桉木屑中的半纤维素和木质素快速液化;液化残渣的主要成分为未降解的结晶区纤维素(结晶度75%左右),液化产物水不溶性级分主要为木质素的降解产物,液化产物水溶性级分主要由纤维素的降解产物乙酰丙酸以及乙酰丙酸甲酯组成。 展开更多
关键词 离子液体 桉木屑 液化 残渣 可溶物
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柴油机排气微粒可溶有机成份及苯并(a)芘的研究 被引量:1
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作者 彭美春 季雨 +1 位作者 张华 刘巽俊 《吉林工业大学学报》 CSCD 1989年第4期28-33,共6页
本文用溶剂萃取法和热重法测量了柴油机排气微粒中可溶有机成份(SOF),研究了SOF随发动机负荷的变化关系,并比较了溶剂萃取法与热重法所得结果。还对微粒中的苯并(a)芘进行了定量分析。
关键词 柴油机 排气微粒 可溶有机成份 BAP
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Biomarker responses in the bivalve Chlamys farreri to the water-soluble fraction of crude oil
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作者 蒋凤华 张丽 +2 位作者 杨佰娟 郑立 孙承君 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第4期853-861,共9页
To investigate the effect of the water soluble fraction of crude oil(WSF) on marine bivalves, the scallop C hlamys farreri was exposed to three WSF concentrations(0.18 mg/L, 0.32 mg/L, and 0.51 mg/L, respectively) in ... To investigate the effect of the water soluble fraction of crude oil(WSF) on marine bivalves, the scallop C hlamys farreri was exposed to three WSF concentrations(0.18 mg/L, 0.32 mg/L, and 0.51 mg/L, respectively) in seawater. Petroleum hydrocarbon contents in scallops and a suite of enzymes [7-Ethoxyresorufin-O-deethylase(EROD), aryl hydrocarbon hydroxylase(AHH), glutathione S-transferase(GST), and glutathione peroxidase(GPx)] in gills and digestive glands were monitored over 10 days. The results revealed that WSF affected the activity of the four enzymes in the gills and digestive glands. EROD activity in the gills was significantly induced in most individuals of the three test groups, while in the digestive gland it was significantly induced in the low-concentration group within 4 days but was inhibited in the middle- and high-concentration groups on days 1, 4, and 10. AHH activity in the gills of all treatment groups was significantly induced on day 1. In the digestive gland, AHH activity was induced in most individuals from the treatment groups. In all treatment groups, GST activity was significantly inhibited from days 2 to 10 in the gills and was induced after day 4 in the digestive gland. GPx activity in the gills was significantly inhibited throughout the exposure period in all treatment groups. There was no overall significant difference in GPx activity in the digestive gland between the control and treatment groups. Our results also revealed that petroleum hydrocarbon concentrations in the tissues increased linearly with exposure time. EROD activity in the digestive gland and GST and GPx activity in the gill tissue were negatively correlated with petroleum hydrocarbon body burden. These enzymes play important roles in detoxification and can act as potential biomarkers for monitoring petroleum hydrocarbon contaminants in the marine environment. 展开更多
关键词 crude oil water soluble fraction (WSF) Chlamysfarreri biomarkers DETOXIFICATION
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Effect of Diesel Fuel Composition on Exhaust Emissions
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作者 Shen Yanjin (SINOPEC Research Institute of Petroleum Processing,Beijing 100083) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第4期42-47,共6页
In this paper,the influence of aromatic content,one of main fuel properties,on diesel particulate emissions was studied at five steady-state operating conditions using a heavy-duty Perkins 4.236 engine.Detailed analys... In this paper,the influence of aromatic content,one of main fuel properties,on diesel particulate emissions was studied at five steady-state operating conditions using a heavy-duty Perkins 4.236 engine.Detailed analysis of the particulate showed the presence of biologically active polynuclear aromatic hydrocarbons(PAH) in high concentration.Unburnt PAH in liquid fuel are identified to be the dominant source of particulate PAH.Diesel particulates are also considered a potential health hazard because of the presence of PAH in the SOF of the particulates and some of these PAH are known to be carcinogenic. 展开更多
关键词 exhaust emissions aromatics content PARTICULATE soluble organic fraction(SOF) carcinogenic PAH
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不同有机物料还田对东北黑土活性有机碳的影响 被引量:95
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作者 梁尧 韩晓增 +1 位作者 宋春 李海波 《中国农业科学》 CAS CSCD 北大核心 2011年第17期3565-3574,共10页
【目的】阐明不同有机物料培肥对黑土总有机碳和活性有机碳组分的影响,探讨合理调控农田土壤肥力的施肥模式。【方法】以黑龙江省海伦市国家野外科学观测研究站试验区上进行了6年田间定位试验的小区土壤为研究对象,通过对土壤活性有机... 【目的】阐明不同有机物料培肥对黑土总有机碳和活性有机碳组分的影响,探讨合理调控农田土壤肥力的施肥模式。【方法】以黑龙江省海伦市国家野外科学观测研究站试验区上进行了6年田间定位试验的小区土壤为研究对象,通过对土壤活性有机碳的提取以及室内作物栽培试验,对比和分析不同有机物料配施化肥处理下土壤活性有机碳与土壤生产力的变化。【结果】与试验初期相比,经过6年单施化肥处理后,土壤总有机碳(TOC)、微生物量碳(MBC)、水溶性有机碳(WSOC)以及轻组有机碳(LFOC)的含量显著下降;而有机无机配施则显著提高了土壤有机碳及各活性有机碳组分的含量。不同有机物料还田对土壤总有机碳和各活性有机碳组分的作用存在显著差异,作物秸秆与化肥配施更有助于TOC和LFOC的积累,其中以玉米秸秆配施化肥的效果最为突出,与单施化肥相比,增幅分别为26%和136%;粪肥配施化肥对MBC和WSOC的积累效果优于作物秸秆,其中以猪粪配施化肥的效果最为突出,与单施化肥相比,增幅分别为52%和85%。室内作物栽培试验表明,单施化肥处理将引起土壤生产力的下降,有机无机配施则能明显改善土壤生产力水平。不同有机物料配施化肥对土壤生产力的提升效果表现为:猪粪>牛粪>小麦秸秆≈玉米秸秆。【结论】在东北黑土区,不同有机物料处理之间土壤总有机碳、活性有机碳以及土壤生产力存在明显差异,玉米秸秆配施化肥能够显著提高土壤总有机碳和轻组有机碳的含量,而猪粪配施化肥则更有助于土壤微生物量碳和水溶性有机碳的积累,有利于土壤生产力的提升。 展开更多
关键词 有机物料还田 微生物量碳 水溶性有机碳 轻组有机碳 土壤生产力
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用^(32)P示踪法研究石灰性土壤中磷素的形态及有效性变化 被引量:53
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作者 冯固 杨茂秋 +1 位作者 白灯莎 黄全生 《土壤学报》 CAS CSCD 北大核心 1996年第3期301-307,共7页
水溶性磷肥施入土壤后,其有效性随时间延长而降低,短期内(2个月)有2/3左右变成不可提取态磷(Olsen)法,其形态主要是Ca8—P,Al—P,Fe—P型磷酸盐。在种植玉米时,施入的磷肥22.6—27.8%转化成Ca... 水溶性磷肥施入土壤后,其有效性随时间延长而降低,短期内(2个月)有2/3左右变成不可提取态磷(Olsen)法,其形态主要是Ca8—P,Al—P,Fe—P型磷酸盐。在种植玉米时,施入的磷肥22.6—27.8%转化成Ca2—P,27.5—30.6%转化成Ca8—P,9.1—10.0%转化成Al—P,10.5—15.6%转化成Fe—P,11.3—18.8%被玉米吸收利用。Ca2—P、Ca8—P、Al—P和Fe—P型磷酸盐对玉米生长都有一定的肥效,它们对植物干物质生产的效率(即引入每百毫克磷所产生的植株干重)的大小顺序是:Ca2—P>Al—P>Ca8—P>Fe—P。Ca(10)—P型磷酸盐对玉米生长无效。 展开更多
关键词 石灰性土壤 水溶性磷肥 形态 有效性变化
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桃园生草对土壤有机碳及活性碳库组分的影响 被引量:37
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作者 王耀锋 邵玲玲 +4 位作者 刘玉学 吕豪豪 陈庆飞 廖敏 杨生茂 《生态学报》 CAS CSCD 北大核心 2014年第20期6002-6010,共9页
果园生草是解决传统清耕引起的水土流失、土壤有机质减少、土壤肥力下降和果品品质变劣的果园地面管理措施之一。阐明不同牧草种类对土壤有机碳及其活性组分的影响是实现果园土壤生态管理、促进有机果品生产技术体系完善和果园土壤质量... 果园生草是解决传统清耕引起的水土流失、土壤有机质减少、土壤肥力下降和果品品质变劣的果园地面管理措施之一。阐明不同牧草种类对土壤有机碳及其活性组分的影响是实现果园土壤生态管理、促进有机果品生产技术体系完善和果园土壤质量提高过程中亟待解决的问题。通过研究桃园人工种植黑麦草和毛苕子对土壤总有机碳(TOC)及其活性组分(微生物量碳(MBC)、水溶性有机碳(WSOC)、轻组有机碳(LFOC)、重组有机碳(HFOC)以及团聚体有机碳)的影响,探明豆科牧草与禾本科牧草种植对桃园土壤有机碳及其组分的影响及其差异。结果表明:与清耕对照(CK)相比,种植黑麦草后土壤TOC、MBC和WSOC分别提高了5.13%、76.4%和18.1%,种植毛苕子土壤LFOC提高了11.3%,土壤HFOC降低了13.2%,但对土壤TOC、MBC和WSOC未产生显著影响。此外,黑麦草显著提高土壤较大粒级(>74μm)团聚体有机碳含量,而毛苕子则显著降低土壤较小粒级(<2000μm)团聚体有机碳含量。对提高TOC而言,在桃园种植禾本科牧草黑麦草优于豆科牧草毛苕子。土壤MBC、WSOC、LFOC以及HFOC可以作为指示桃园土壤质量提高与否、表征土壤有机碳变化的敏感指标。 展开更多
关键词 桃园 果园生草 微生物量碳 水溶性有机碳 轻/重组有机碳
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广州城区秋季大气PM_(2.5)中主要水溶性无机离子分析 被引量:35
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作者 吕文英 徐海娟 王新明 《环境科学与技术》 CAS CSCD 北大核心 2010年第1期98-101,共4页
分别在广州市中心城区高楼顶(距地50m)和交通干线路边(距地1.2m),于2006年秋季连续一周采集了大气PM2.5样品,对比分析了SO42-、NO3-、Cl-、F-、Na+、NH4+、Ca2+、K+、Mg2+等9种水溶性无机离子含量。结果表明,楼顶相对充分混合大气中PM2.... 分别在广州市中心城区高楼顶(距地50m)和交通干线路边(距地1.2m),于2006年秋季连续一周采集了大气PM2.5样品,对比分析了SO42-、NO3-、Cl-、F-、Na+、NH4+、Ca2+、K+、Mg2+等9种水溶性无机离子含量。结果表明,楼顶相对充分混合大气中PM2.5的质量浓度范围59.5~129.5μg/m3,均值为83.7μg/m3;交通干线路边大气PM2.5的质量浓度范围为108.4~132.2μg/m3,均值为121.1μg/m3。9种离子总浓度平均达到50.9(楼顶)和44.1(路边)μg/m3,占PM2.5质量浓度的60.8%(楼顶)和36.4%(路边)。SO42-和NO3-为水溶性无机离子主要组成,其占PM2.5质量浓度的比例均是楼顶高于路边,显示二次气溶胶对楼顶充分混合大气中PM2.5有较大贡献,而路边样品中一次来源贡献相对较大。计算表明采样期间海盐对广州大气PM2.5中的水溶性组分贡献较小。NH4+当量浓度远小于SO42-和NO3-的当量浓度,中和度远<1,反映PM2.5酸性较强,且楼项PM2.5粒子酸性高于路边样品。 展开更多
关键词 细粒子(PM25) 水溶性组份 硫酸盐 硝酸盐 二次气溶胶 粒子酸性 广州
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