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Genome-Wide Association Study for Certain Carcass Traits and Organ Weights in a Large White×Minzhu Intercross Porcine Population 被引量:4
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作者 LIU Xin WANG Li-gang +5 位作者 LIANG Jing YAN Hua ZHAO Ke-bin LI Na ZHANG Long-chao WANG Li-xian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第12期2721-2730,共10页
Porcine carcass traits and organ weights have important economic roles in the swine industry. A total of 576 animals from a Large White×Minzhu intercross population were genotyped using the Illumina PorcineSNP60K... Porcine carcass traits and organ weights have important economic roles in the swine industry. A total of 576 animals from a Large White×Minzhu intercross population were genotyped using the Illumina PorcineSNP60K Beadchip and were phenotyped for 10 traits, speciifcally, backfat thickness (6-7 libs), carcass length, carcass weight, foot weight, head weight, heart weight, leaf fat weight, liver weight, lung weight and slaughter body weight. The genome-wide association study (GWAS) was assessed by Genome Wide Rapid Association using the mixed model and regression-genomic control approach. A total of 31 single nucleotide polymorphisms (SNPs) (with the most signiifcant SNP being MARC0033464, P value=6.80×10-13) were located in a 9.76-Mb (31.24-41.00 Mb) region on SSC7 and were found to be signiifcantly associated with one or more carcass traits and organ weights. High percentage of phenotypic variance explanation was observed for each trait ranging from 31.21 to 67.42%. Linkage analysis revealed one haplotype block of 495 kb, in which the most signiifcant SNP being MARC0033464 was contained, on SSC7 at complete linkage disequilibrium. Annotation of the pig reference genome suggested 6 genes (GRM4, HMGA1, NUDT3, RPS10, SPDEF and PACSIN1) in this candidate linkage disequilibrium (LD) interval. Functional analysis indicated that the HMGA1 gene presents the prime biological candidate for carcass traits and organ weights in pig, with potential application in breeding programs. 展开更多
关键词 genome-wide association study (GWAS) carcass trait HMGA1 gene organ weight PIG
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Effects of Aroclor 1254 on reproductive organ weight,sperm quality and testicular mitochondria oxidative stress of Boleophthalmus pectinirostris
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作者 HE Shanying WU Qiuling SUN Mengdie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第6期65-71,共7页
Boleophthalmus pectinirostris is an amphibious economic fish and wildly distributed in the southeast coast of China. In this study, Aroclor 1254 was intraperitoneally injected into B. pectinirostris with 1, 2 and 4 ... Boleophthalmus pectinirostris is an amphibious economic fish and wildly distributed in the southeast coast of China. In this study, Aroclor 1254 was intraperitoneally injected into B. pectinirostris with 1, 2 and 4 μg/(g · d) for 28 d to assay the reproductive organ weight, the sperm quality (sperm concentration and motility), and the testicular mitochondrial testicular mitochondria oxidative stress. The results show that the sperm number and motility in seminal vesicles, the absolute weight of testes and seminal vesicles of B. pectinirostris treated with 2 and 4 μg/(g · d) Aroclor 1254 decreased significantly as compared to the controls (p 0.05), while those treated with 1 μg/(g · d) Aroclor 1254 had no significant effects on these indictors. For the relative weight of reproductive organs, significant reduction (p 0.05) was only observed in the seminal vesicles of B. pectinirostris treated with 4 μg/(g · d). SOD activities and GSH levels in all the Aroclor 1254 treatments were significantly lower than those of the controls (p 0.05). The activities of CAT, GPx, GR and the levels of Vit C also decreased significantly in comparison with the controls (p 0.05) at the higher dose of 2 and 4 μg/(g · d) Aroclor 1254 treatments. In addition, both H 2 O 2 level and MDA content in testicular mitochondria of B. pectinirostris had a close correlation with Aroclor 1254 dosage, and were significantly higher than the controls (p 0.05). Those indicate that Aroclor 1254 can induce the oxidative stress of testicular mitochondria, and impair the reproductive function of male B. pectinirostris. 展开更多
关键词 PCBS Boleophthalmus pectinirostris organ weight sperm quality oxidative stress
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Effects of n-3 Fatty Acids Supplementation on Performance, Relative Organ Weight and Fatty Acid Composition of Thigh Meat in Broiler Chickens
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作者 Li Yuanfeng Wang Yachao +1 位作者 Ao Xiang He Jian 《Animal Husbandry and Feed Science》 CAS 2018年第5期287-292,共6页
This study was conducted to evaluate the effects of dietary supplementation with marine microbe accumulating n-3 fatty acids on growth performance, relative organ weight and fatty acid composition of thigh meat in bro... This study was conducted to evaluate the effects of dietary supplementation with marine microbe accumulating n-3 fatty acids on growth performance, relative organ weight and fatty acid composition of thigh meat in broilers. A total of 480 broilers were randomly allotted to three treat-ments with eight replications per treatment and 20 chicks per pen. A corn-soybean meal-based diet was formulated as a control diet and the broilers were then provided with one of the following dietary treatments:(1) CON(basal diet);(2) N0.1(basal diet+0.10% marine microbe accumulating n-3 fatty acids);(3) N0.2(basal diet+0.20% marine microbe accumulating n-3 fatty acids). No significant differences were observed in the growth performance or the relative organ weight among treatments. However, the levels of saturated fatty acids(SFA) and monounsaturated fatty acids(MUFA)were significantly lower(P<0.05) in groups that received the n-3 fatty acids treatments, whereas polyunsaturated fatty acids(PUFA) were increased(P<0.05) significantly in these groups. Overall, these results indicate that dietary supplementation with marine microbe accumulating n-3 fatty acids can increase PUFA and decrease SFA and MUFA in thigh meat. 展开更多
关键词 BROILER Fatty acid composition Marine microbe accumulating n-3 fatty acids Growth performance Relative organ weight
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Characteristics and distribution of low molecular weight organic acids in the sediment porewaters in Bosten Lake, China 被引量:7
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作者 Min Xiao Fengchang Wu +3 位作者 Haiqing Liao Wen Li Xinqing Lee Rongsheng Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第3期328-337,共10页
The composition and vertical profiles of low molecular-weight organic acids (LMWOAs) and the contribution of them to dissolved organic matter (DOM) in sediment porewaters in Bosten Lake, Xinjiang, China were inves... The composition and vertical profiles of low molecular-weight organic acids (LMWOAs) and the contribution of them to dissolved organic matter (DOM) in sediment porewaters in Bosten Lake, Xinjiang, China were investigated. The results showed that total concentration of LMWOAs was up to 94.5 μmol/L and their proportion in DOM was 5.6%, suggesting that LMWOAs were important chemical components in DOM in lake sediment porewaters. Among the seven LMWOAs, pyruvic and acetic acid had the highest concentrations with 26.30 and 8.31 μmol/L, accounting for 51.4% and 14.92% of LMWOAs, respectively. Trifluoroacetic and sorbic acid had the lowest concentrations, indicating that the compositions of LMWOAs in relative reducing environments were largely different from those reported in glacier, atmosphere and soils. The concentrations of lactic, acetic, formic, sorbic and oxalic acid decreased with increasing depth, probably relating to stronger microbial activities in the initial stage of early diagenesis. Trifluoroacetic acid was mainly anthropogenic with its concentration, showing a diusive trend from the surface to bottom sediments. The concentrations of lactic acid and nitrate generally showed a consistent profile. The increasing concentration of pyruvic acid in the vertical profile was just opposite to that of sulfate, revealing a significant negative relationship between them. Oxalic acid remained constant except for an obvious peak at 6 cm depth. The results indicated the diversities in sources and behaviors for various LMWOAs during early diagenesis in sediments. 展开更多
关键词 dissolved organic matter low molecular-weight organic acids sediment porewaters early diagenesis
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Effect of Dissolved Organic Matter on Titanium Dioxide Nanoparticles in Aquatic Environment:Molecular Weight Fractions 被引量:1
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作者 Xiaonan Yang Dongmei Liu Fuyi Cui 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第5期38-48,共11页
At present,a growing number of consumer products contain engineered nanoparticle TiO2(nano⁃TiO2),which has resulted in the consequences of nano⁃TiO2 entering the aquatic environment directly or indirectly at some stag... At present,a growing number of consumer products contain engineered nanoparticle TiO2(nano⁃TiO2),which has resulted in the consequences of nano⁃TiO2 entering the aquatic environment directly or indirectly at some stage.The fate of nano⁃TiO2 in the aquatic environment has become the key factor which affects its safety application and nanoecotoxicology.This paper aims to investigate how the dissolved organic matters(DOM),especially the molecular weight fractions in the aquatic environment,affect the aggregation,stability,and fate of nano⁃TiO2,and the interaction mechanism of DOM and nano⁃TiO2.Results of dynamic light scattering(DLS)showed that the molecular weight of DOM molecules caused different aggregation rates of nano⁃TiO2 in aqueous solution.Fourier Transform infrared spectroscopy(FTIR)results indicated the molecular structure is characteristics of DOM fractions and the mechanisms of bonds formation between DOM and nano⁃TiO2.Results of three⁃dimensional excitation⁃emission matrices(3D⁃EEM)confirmed the FTIR results and implied the increase of the stability of theπ-πconjugated system in the presence of DOM.In addition,low molecular weight of DOM fractions appeared to show more affinity with nano⁃TiO2 than high molecular weight fractions. 展开更多
关键词 titanium dioxide nanoparticles dissolved organic matter different molecular weight organics
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Molecular Weight Distribution of Dissolved Organic Matter in Lake Hongfeng Determined by High Performance Size Exclusion Chromatography (HPSEC) With On-Line UV-Vis Absorbance and Fluorescence Detection 被引量:3
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作者 岳兰秀 吴丰昌 +3 位作者 刘丛强 黎文 王静 梅毅 《Chinese Journal Of Geochemistry》 EI CAS 2004年第3期275-283,共9页
The molecular weight distribution (MWD) of dissolved organic matter (DOM) in lake waters from Lake Hongfeng was examined using high performance size exclusion chromatography (HPSEC) with UV-vis absorbance and fluoresc... The molecular weight distribution (MWD) of dissolved organic matter (DOM) in lake waters from Lake Hongfeng was examined using high performance size exclusion chromatography (HPSEC) with UV-vis absorbance and fluorescence detection. The elution curves obtained by absorbance and fluorescence techniques expressed similar patterns, with the exception of diminishing of large fraction and the peaks behind several seconds in fluorescence chromatograms. According to its molecular weight (MW), DOM in water samples is divided into several fractions: large ({>3.5} kDa); medium-large ({3.5}-{2.0} kDa); medium ({2.0}-{1.0} kDa) and small ({<1.0} kDa). The average molecular weight was calculated using the elution curve detected by UV-vis absorbance and fluorescence detection techniques. The results showed that the weight-average molecular weight (Mw) and number-average molecular weight (Mn) calculated by UV-vis absorbance techniques range from 1750 to 2050 Dalton and from 1450 to 1850 Dalton, respectively. And the Mw and Mn obtained by fluorescence detection are lower by 50 to 400 Dalton. As a reference, the molecular weight of Fluka humic acid (FHA) is larger than that of water samples by about 200 Dalton. The average molecular weight of DOM for water samples collected in March and July was compared. The results revealed that the molecular weight is lower for water samples obtained in July than that obtained in March, indicating the ambient environment has an influence on the molecular weight, including photo-degradation and biological activity. 展开更多
关键词 液化有机物 分子量 平均数 吸收比 荧光性 聚合化合物 湖水生物化学
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Effects of low molecular weight organic acids on sorption and desorption behavior of p-chlorophenol by yellow earth
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作者 Daoyong ZHANG Xiangliang PAN +2 位作者 Shuimu LIAO Chenglin HUANG Jingmei ZHANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期133-133,共1页
关键词 黄土 吸附作用 有机酸 氯酚 土壤化学
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Utilizing Water Treatment Residuals for Phosphorus Removal:Batch Trials,Column Trials and Effects of Three Low-Molecular-Weight Organic Acids
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作者 任新 崔崇威 +1 位作者 赵雪松 许铁夫 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期304-311,共8页
Phosphorus( P) has been recognized as a major limited nutrient responsible for the eutrophication of surface waters. Water treatment residuals( WTRs) are safe by-products of water treatment plants and are cost-efficie... Phosphorus( P) has been recognized as a major limited nutrient responsible for the eutrophication of surface waters. Water treatment residuals( WTRs) are safe by-products of water treatment plants and are cost-efficient adsorbents. In this study, batch experiments and column experiments based on WTRs were employed to study the characteristics of P adsorption and the effects of lowmolecular-weight organic acids( LMWOAs)( citric acid, oxalic acid,and tartaric acid) on P adsorption. Different models of adsorption were used to describe equilibrium and kinetic data. The adsorption data were fitted well by a pseudo-second order kinetic model. The adsorption process was determined to be controlled by three steps of diffusion mechanisms through the intra-particle model.The adsorption equilibrium was well described by the Langmuir,Freundlich,Redlich-Peterson,and Sips isotherm models. Batch and continuous flow experiments indicated that the LMWOAs exhibited inhibitory action,and as pH increased,the inhibitory action became weaker for all the three acids. The effect of LMWOAs concentration was not significant on inhibition. The effects of LMWOAs were closely related to reaction time. 展开更多
关键词 adsorption capability PHOSPHORUS water treatment residuals low-molecular-weight organic acids(LMWOAs)
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Detection of Quantitative Trait Loci Associated with Several Internal Organ Traits and Teat Number Trait in a Pig Population 被引量:1
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作者 张敬虎 熊远著 +6 位作者 左波 雷明刚 蒋思文 李凤娥 郑嵘 李家连 徐德全 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第4期307-314,共8页
Quantitative trait loci (QTL) were detected for 8 internal organ traits, 3 carcass length traits, and teat number trait in 214 pigs in a resource population that included 180 F2 individuals. A total of 39 microsatel... Quantitative trait loci (QTL) were detected for 8 internal organ traits, 3 carcass length traits, and teat number trait in 214 pigs in a resource population that included 180 F2 individuals. A total of 39 microsatellite markers were examined on SSC4, SSC6, SSC7, SSC8, and SSC13. The genetic traits included heart weight (HW), lung weight (LW), liver and gallbladder weight (LGW), spleen weight (SPW), stomach weight (STW), small intestine weight (S1W), large intestine weight (LIW), kidney weight (KW), carcass length to the first cervical vertebra (CL1), carcass length to the first thoracic vertebra (CL2), rib numbers (RNS), and teat numbers (TNS). Results indicated that, 3 highly significant QTL (P≤0.01 at chromosome-wise level) for HW (at 30 cM on SSC6), RNS (at 115 cM on SSC7), TNS (at 110 cM on SSC7), and 6 significant QTL (P≤0.05 at chromosome-wise level) for LW (at 119 cM on SSC13), LGW (at 94 cM on SSC6), SPW (at 106 cM on SSC8), SIW (0 cM on SSC4), LIW (170 cM on SSC 4), and TNS (at 95 cM on SSC6) were detected. The phenotypic variances for which these QTL were accounted ranged from 0.04 % to 14.06 %. Most of these QTL had not been previously reported. 展开更多
关键词 PIG quantitative trait loci (QTL) internal organ weight traits carcass length traits teat number trait
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低分子量有机酸对亚热带地区典型土壤磷吸附的影响
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作者 张苗苗 黄鑫星 +3 位作者 罗沛 刘锋 宫殿林 肖润林 《湖南农业科学》 2024年第2期23-30,共8页
为探索低分子量有机酸对亚热带地区典型土壤磷吸附的影响,采用批处理法研究了柠檬酸和草酸对旱地土、水稻土磷素吸附特征的作用,重点探讨了不同浓度有机酸和柠檬酸钠、有机酸加入顺序等对土壤磷吸附的影响。结果表明:柠檬酸和草酸显著... 为探索低分子量有机酸对亚热带地区典型土壤磷吸附的影响,采用批处理法研究了柠檬酸和草酸对旱地土、水稻土磷素吸附特征的作用,重点探讨了不同浓度有机酸和柠檬酸钠、有机酸加入顺序等对土壤磷吸附的影响。结果表明:柠檬酸和草酸显著降低了土壤磷吸附动力学的颗粒内扩散模型拟合度,减弱了磷素在土壤颗粒内部扩散过程。Langmuir和Freundlich方程对有机酸存在下土壤磷吸附等温数据均有较好的拟合效果(R2=0.863~0.996)。有机酸降低了土壤磷素最大理论吸附量。土壤磷吸附量与有机酸浓度呈指数函数关系,0.1~5 mmol/L有机酸对土壤磷吸附的影响最大。有机酸浓度小于1 mmol/L时,柠檬酸对土壤磷素吸附的抑制程度大于草酸;而当浓度大于5 mmol/L时,草酸的抑制程度更大。在相同浓度时,0.1~5 mmol/L的柠檬酸钠比柠檬酸对土壤磷吸附能力抑制程度更大,先加入有机酸进一步降低了土壤对磷素吸附量,说明阴离子竞争吸附是低浓度柠檬酸降低土壤磷吸附能力的主要原因,而柠檬酸浓度为5~50 mmol/L时,有机酸与土壤铁铝等金属离子的络合作用占主导。 展开更多
关键词 磷吸附 土壤 柠檬酸 草酸 低分子量有机酸
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饲粮中添加芦丁对努比亚山羊体尺指标、瘤胃发酵和器官发育的影响
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作者 刘宇航 占今舜 +4 位作者 计接权 王海波 王丽媛 赵生国 霍俊宏 《中国饲料》 北大核心 2024年第1期100-107,共8页
为研究饲粮中添加芦丁对努比亚山羊体尺指标、瘤胃发酵和器官发育的影响,试验选择2月龄健康、体重相近的努比亚山羊母羊36只,随机分为3组,每组12只羊。分别饲喂基础饲粮(对照组)、基础饲粮+25 mg/kg芦丁(试验Ⅰ组)和基础饲粮+50 mg/kg芦... 为研究饲粮中添加芦丁对努比亚山羊体尺指标、瘤胃发酵和器官发育的影响,试验选择2月龄健康、体重相近的努比亚山羊母羊36只,随机分为3组,每组12只羊。分别饲喂基础饲粮(对照组)、基础饲粮+25 mg/kg芦丁(试验Ⅰ组)和基础饲粮+50 mg/kg芦丁(试验Ⅱ组)。试验预饲期10 d,正试期60 d。饲养结束后进行屠宰。结果表明:(1)与对照组相比,正试期第10天试验Ⅰ组和Ⅱ组山羊管围分别显著提高5.57%(P<0.05)、6.93%(P<0.05),正试期第60天试验Ⅱ组管围和体高分别显著降低6.54%(P<0.05)、8.23%(P<0.05),试验Ⅱ组体长相对于Ⅰ组显著提高3.69%(P<0.05)。(2)与对照组相比,试验Ⅰ组山羊丙酸和总挥发性脂肪酸浓度分别显著降低42.14%(P<0.05)、21.62%(P<0.05)。试验Ⅱ组乙酸和总挥发性脂肪酸浓度分别显著降低29.23%(P<0.05)、29.43%(P<0.05)。(3)与对照组相比,试验Ⅰ组山羊瘤胃产琥珀酸丝状杆菌、溶纤维丁酸弧菌、乳酸菌和黄色瘤胃球菌基因相对表达量分别提高271.57%(P<0.01)、1686.09%(P<0.05)、280.00%(P<0.01)和16226.73%(P<0.01),试验Ⅱ组白色瘤胃球菌、溶纤维丁酸弧菌、栖瘤胃普雷沃菌、乳酸菌和黄色瘤胃球菌基因相对表达量分别提高130.56%(P<0.01)、381.74%(P<0.05)、188.00%(P<0.01)、546.00%(P<0.01)、25624.75%(P<0.01),嗜淀粉瘤胃杆菌基因相对表达量降低57.89%(P<0.05)。试验Ⅰ组与试验Ⅱ组嗜淀粉瘤胃杆菌、产琥珀酸丝状杆菌、白色瘤胃球菌、溶纤维丁酸弧菌、栖瘤胃普雷沃菌和乳酸菌基因相对表达量对比差异极显著(P<0.01)或显著(P<0.05),黄色瘤胃球菌基因相对表达量对比差异不显著(P>0.05)。(4)与对照组相比,试验Ⅰ组山羊心脏重量、瓣胃重量和指数分别显著降低14.50%(P<0.05)、24.00%(P<0.05)、20.00%(P<0.05),试验Ⅱ组肝脏重量和指数分别提高12.54%(P<0.01)、14.95%(P<0.01),瓣胃重量和指数分别显著降低29.41%(P<0.05)、28.57%(P<0.05)。(5)与对照组相比,试验Ⅰ组山羊十二指肠VH/CD和回肠VH分别显著降低0.13%(P<0.05)、15.42%(P<0.05),试验Ⅱ组十二指肠VH、CD、回肠VH、VH/CD分别显著降低29.19%(P<0.05)、20.92%(P<0.05)、18.23%(P<0.05)、26.14%(P<0.05),空肠CD显著提高15.63%(P<0.05)。综上所述,本试验条件下,饲粮中添加高剂量芦丁可以增加努比亚山羊部分瘤胃菌群的数量,影响瘤胃发酵,对胃肠道发育产生负面影响。 展开更多
关键词 芦丁 山羊 体尺 瘤胃发酵 细菌菌群 器官重量 肠道发育
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益智清心方单次给药毒性试验研究
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作者 谭丽博 吴素素 +4 位作者 魏微 曹宇 马丽娜 裴卉 李浩 《世界中医药》 CAS 北大核心 2024年第16期2399-2403,共5页
目的:观察24 h内益智清心方经口灌胃后的急性毒性反应和死亡情况,评价益智清心方的安全性,为进一步的重复给药毒性试验以及临床用药提供参考。方法:选取24~33 g ICR小鼠,雌雄各半,随机分为益智清心方组和空白对照组,采用最大给药量法,... 目的:观察24 h内益智清心方经口灌胃后的急性毒性反应和死亡情况,评价益智清心方的安全性,为进一步的重复给药毒性试验以及临床用药提供参考。方法:选取24~33 g ICR小鼠,雌雄各半,随机分为益智清心方组和空白对照组,采用最大给药量法,以最大灌胃体积40 mL/kg计,分别给予等体积的益智清心方药液和纯水,2次/d,给药期间定期监测小鼠一般状况和体质量,14 d后,收集血、尿样本,并进行大体解剖,评价益智清心方对脏器系数、血常规、尿常规等安全性指标的影响。结果:ICR小鼠按40 mL/kg经口灌胃给予最大可配制浓度为0.36 g干浸膏/mL的益智清心方药液,当日2次,累积剂量为98.6 g生药/kg体质量,约相当于成人临床拟用剂量的298倍(按公斤体质量计算)和38倍(按体表面积计算)。各组小鼠均未发现毒性相关的症状和死亡,益智清心方组小鼠在体质量、脏器系数、血常规、尿常规指标方面与对照组小鼠比较差异均无统计学意义(均P>0.05)。结论:本试验条件下,益智清心方的单次给药毒性试验中未见明显的急性毒性反应及死亡,提示其最大耐受量(MTD)>98.6 g生药/kg体质量。 展开更多
关键词 临床前研究 单次给药毒性 小鼠 阿尔茨海默病 益智清心方 安全性 体质量 脏器系数
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4种常见木质素有机溶剂法分级的研究进展
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作者 程鹏超 孙衍宁 +4 位作者 李尧 李继庚 王兴 孙广卫 张馨月 《中国造纸学报》 CAS CSCD 北大核心 2024年第2期1-8,共8页
随着对木质素基生物质材料开发和研究的逐渐深入,进一步提高木质素基生物质材料的性能,需对木质素原料进行结构分级。有机溶剂法分级是一种可以获得具有特定理化性质木质素的简单可行的分级方法。本文总结了近年来采用有机溶剂法,对硫... 随着对木质素基生物质材料开发和研究的逐渐深入,进一步提高木质素基生物质材料的性能,需对木质素原料进行结构分级。有机溶剂法分级是一种可以获得具有特定理化性质木质素的简单可行的分级方法。本文总结了近年来采用有机溶剂法,对硫酸盐木质素、有机溶剂木质素、碱木质素和酶解木质素4种常见木质素进行分级,且分级效果较好的研究成果,利用分子质量及分子质量分布,以及醇羟基、酚羟基、甲氧基等官能团含量作为分级评价指标,比较了不同分级策略所使用的单一或多种有机溶剂的分级特点和优缺点,并对木质素分级研究作简要总结和展望。 展开更多
关键词 木质素 分级方法 有机溶剂 分子质量分布
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好氧堆肥污泥农用后溶解性有机质释放特征
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作者 时聪慧 张瑞昌 +6 位作者 朱书法 李欣彤 周新全 张宁 荣亮 杨丽珍 魏学锋 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第4期1011-1017,共7页
研究污泥农用后溶解有机质(DOM)的释放特征,有助于评价和预测土壤中共存污染物的环境行为和效应。以河南省洛阳市某污泥处理厂好氧堆肥后的市政污泥作为样本,利用扫描电子显微镜(SEM)、总有机碳分析仪、紫外-可见吸收光谱(UV-Vis)、凝... 研究污泥农用后溶解有机质(DOM)的释放特征,有助于评价和预测土壤中共存污染物的环境行为和效应。以河南省洛阳市某污泥处理厂好氧堆肥后的市政污泥作为样本,利用扫描电子显微镜(SEM)、总有机碳分析仪、紫外-可见吸收光谱(UV-Vis)、凝胶渗透色谱(GPC)、三维荧光光谱(3D-EEM)、傅里叶变换红外光谱(FTIR)和核磁共振波谱(NMR)等表征技术,研究污泥农用后释放DOM的浓度、分子量、组成和结构等性质的演变特征。结果表明,污泥还田60 d内,释放的DOM微观形貌上存在较大变化,由致密块状物变为不规则松散物质;污泥农用后释放溶解性有机碳(DOC)量在4.25~6.22 mg·g^(-1)污泥范围,呈现先上升后稳步下降的趋势;释放过程中,污泥DOM的分子量和芳香性等性质也存在显著的变化:污泥DOM重均分子量由0.5 d时2674 g·mol^(-1)的逐渐升高为60 d的129026 g·mol^(-1);污泥还田后释放的DOM分子中芳香性物质逐渐积累;3D-EEM结合平行因子分析(PARAFAC)模型分析污泥释放DOM中的荧光物质,发现DOM中荧光物质主要为类富里酸和类腐殖质,释放过程中,类腐殖质逐渐积累,DOM整体上呈现腐殖化趋势;FTIR图谱表征污泥DOM脂肪族烷烃类物质的减少和芳香烃物质生成。污泥还田后释放DOM数量和性质变化,显著改变土壤中共存污染物环境行为和生态效应。该研究可为评估和预测污泥农用后产生的环境影响提供理论依据,也对市政污泥的资源化利用具有一定指导意义。 展开更多
关键词 污泥农用 溶解性有机质 释放特征 分子量 芳香性
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多次低剂量应用草酸促进芹菜减磷生产
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作者 孙项欣 牛明芬 +1 位作者 马建 黄斌 《土壤与作物》 2024年第3期348-358,共11页
针对蔬菜作物生长期一次性低剂量应用草酸土壤磷素活化作用时效短和一次性高剂量应用草酸风险较大的缺点,选用多次低剂量灌溉应用草酸的方法,以期持续、安全地活化设施菜地土壤盈余磷素,推动设施蔬菜减磷生产。选用速效磷含量分别为88.6... 针对蔬菜作物生长期一次性低剂量应用草酸土壤磷素活化作用时效短和一次性高剂量应用草酸风险较大的缺点,选用多次低剂量灌溉应用草酸的方法,以期持续、安全地活化设施菜地土壤盈余磷素,推动设施蔬菜减磷生产。选用速效磷含量分别为88.6和46.1mg·kg^(−1)的两个设施菜地土壤(分别简称土壤A和土壤B)开展室内浅层土壤(深度为1 cm)培养试验、无植物和种植芹菜的盆栽土壤(深度17 cm)温室试验,探究多次低剂量应用草酸活化土壤磷素及促进芹菜生产效果。土壤培养试验揭示多次低剂量灌溉应用草酸(每次草酸应用0.36 g·kg^(−1),共5次,每次间隔10 d)均可以持续、平稳地提高土壤A和土壤B的水溶性无机磷(DIP)的含量。无植物的盆栽土壤试验则显示在土壤A中多次低剂量灌溉应用草酸的土壤磷素活化作用集中在0~10 cm土层,特别是0~5 cm土层。盆栽芹菜试验多次应用草酸(芹菜定植30 d应用草酸4次,每次0、0.18或者0.36 g·kg^(−1),每次间隔10 d)的结果显示,土壤A和土壤B施磷分别减量70%和54%的前提下,两个草酸应用剂量均提高芹菜收获时两个土壤0~5 cm土层的DIP含量,在土壤A中增幅显著(分别为92.0%和165%),在土壤B中仅较高草酸剂量下显著增加64.5%;较高草酸剂量的芹菜增产效果不明显,较低草酸剂量的增产效果显著(20.0%~33.6%,P<0.05),在土壤B中更为明显。多次低剂量灌溉应用草酸在其它土壤-蔬菜系统中的效果及风险有待研究。 展开更多
关键词 水溶性无机磷 土壤磷素盈余 土壤磷素活化 土壤深度 须根蔬菜 小分子有机酸
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冶炼厂周边农用地土壤重金属非致癌健康风险评估及修正
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作者 吴健芳 王红梅 《环境工程技术学报》 CAS CSCD 北大核心 2024年第1期112-120,共9页
为科学量化重金属复合暴露产生的非致癌健康风险,引入靶器官毒性剂量(TTD)模型和证据权重分析模型(WOE)对传统评估模型(HRA)的非致癌健康风险进行修正,并以华中某冶炼厂周边农用地土壤重金属为例,探究3种模型对非致癌健康风险评估结果... 为科学量化重金属复合暴露产生的非致癌健康风险,引入靶器官毒性剂量(TTD)模型和证据权重分析模型(WOE)对传统评估模型(HRA)的非致癌健康风险进行修正,并以华中某冶炼厂周边农用地土壤重金属为例,探究3种模型对非致癌健康风险评估结果的影响。结果表明:土壤重金属镉(Cd)、铅(Pb)、铬(Cr)和砷(As)的浓度均值分别为0.37、36.65、69.06和7.66mg/kg,其中Cd、Pb和Cr不同程度超出研究区土壤背景值,4种重金属传统非致癌健康风险值(HI_(HRA))为2.27×10^(-3)~3.35×10^(-1)。经TTD模型和WOE模型修正后4种重金属HI_(TTD)和HI_(WOE)分别为1.64×10^(-2)~5.50×10^(-1)和1.08×10^(-2)~6.09×10^(-1),其中HI_(TTD)、HI_(WOE)均值分别为HI_(HRA)均值的1.88倍和1.17倍。研究显示,对多种重金属复合污染的农用地开展人体非致癌健康风险评估时,需考虑多靶器官效应及重金属间的交互作用,避免传统风险评估方法低估或高估土壤污染对暴露人群产生的实际健康损害。 展开更多
关键词 土壤 重金属 健康风险 靶器官毒性剂量模型 证据权重模型
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新生儿序贯器官衰竭评分对极低出生体重儿晚发败血症死亡的预测价值
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作者 崔铭玲 冯宗太 +1 位作者 杨祖铭 张霞 《徐州医科大学学报》 CAS 2024年第1期43-46,共4页
目的评价新生儿序贯器官衰竭评分(nSOFA)对极低出生体重儿晚发败血症死亡风险的预测价值。方法采用单中心、回顾性病例对照性研究。收集2018—2021年于南京医科大学附属苏州医院(苏州市立医院)新生儿科重症监护室住院的首次患有晚发败... 目的评价新生儿序贯器官衰竭评分(nSOFA)对极低出生体重儿晚发败血症死亡风险的预测价值。方法采用单中心、回顾性病例对照性研究。收集2018—2021年于南京医科大学附属苏州医院(苏州市立医院)新生儿科重症监护室住院的首次患有晚发败血症的95例极低出生体重儿确诊感染时及感染6 h后的nSOFA评分,上述患者以持续使用抗生素后发生的临床结局分为死亡组和存活组。采用受试者工作特征(ROC)曲线评估nSOFA评分对极低出生体重儿晚发败血症死亡风险的预测价值。结果感染后6 h晚发败血症死亡组nSOFA与存活组相比,差异有统计学意义(P<0.01),而在确诊感染时差异无统计学意义(P>0.05)。感染后6 h nSOFA评分预测模型ROC的AUC=0.873(95%CI 0.729~1.00,P=0.000),而确诊感染时AUC=0.541(95%CI 0.32~0.77,P=0.69)。感染后6 h nSOFA评分约登指数最大值为0.687,最佳截断值为6.5分。结论确诊败血症后6 h nSOFA能较好地预测极低出生体重儿的死亡风险。监测nSOFA对改善新生儿脓毒症预后有一定的临床价值。 展开更多
关键词 极低出生体重儿 序贯器官衰竭评分 晚发败血症 死亡 预测价值
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蘑菇渣和稻秸堆肥中不同分子量水溶性有机物含量分布和光谱特征
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作者 程澳 陈丹 +4 位作者 任兰天 纪文超 范行军 刘晓龙 余旭芳 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第5期1330-1337,共8页
分子量(MW)是影响堆肥溶解性有机物(DOM)化学性质和环境行为等的重要因素,目前关于堆肥DOM的MW分布等认识仍不清晰。以蘑菇渣堆肥(MRC)和水稻秸秆堆肥(RSC)中DOM为研究对象,采用超滤分级技术对堆肥DOM中不同MW组分进行分级定量和化学表... 分子量(MW)是影响堆肥溶解性有机物(DOM)化学性质和环境行为等的重要因素,目前关于堆肥DOM的MW分布等认识仍不清晰。以蘑菇渣堆肥(MRC)和水稻秸秆堆肥(RSC)中DOM为研究对象,采用超滤分级技术对堆肥DOM中不同MW组分进行分级定量和化学表征,进而探究不同堆肥DOM中MW组分的分布和光谱特征。DOC结果显示,MRC和RSC中DOM均以>10 kDa的高分子量(HMW)组分组成为主,分别富集有80%和71%的DOC(溶解性有机碳),而中等分子量(5~10 kDa,MMW)和低分子量(<5 kDa,LMW)组分分别占总DOC的12%~15%和9%~15%,表明HMW是决定腐熟堆肥DOM的化学组成和分子结构的关键物质。光谱特征参数(如SUVA_(254)、E_(2)/E_(3)和HIX)结果显示,不同MW的DOM的芳香化程度和腐殖化程度均呈现相同的趋势,即HMW>MMW>LMW;而BIX和FI值则呈现与之相反的分布规律。结果表明堆肥DOM中HMW(高分子组分)组分富集了较多的芳香环等不饱和共轭结构,而MMW和LMW组分具有更高的自生源贡献。三维荧光-平行因子分析结果显示,堆肥DOM及其MW组分主要由3种类腐殖质(C1—C3)和1种类蛋白质(C4)构成。其中,MRC和RSC中的HMW组分均以长波类腐殖酸(C3)组成为主,其含量分别占HMW组分总荧光强度的34%和85%;而两类堆肥中MMW和LMW组分则以类富里酸(C1,41%~53%)和短波类腐殖酸(C2,25%~36%)组成为主。红外光谱(FTIR)结果表明,堆肥DOM中HMW组分含有更多的疏水性苯环结构,而MMW和LMW组分则具有较多的亲水性含氧官能团(如羰基、羧基等)。研究结果促进了对堆肥DOM化学组成和分子结构的认识,为进一步评价堆肥腐熟和稳定化程度及其环境行为等提供了重要的数据参考。 展开更多
关键词 堆肥 水溶性有机物 分子量分级 光谱特征
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胚蛋注射乳酸菌对雏鸡孵化性能和肠道黏膜结构的影响
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作者 卢佳慧 徐久鹏 +5 位作者 李孜恒 范雨欣 常伽翌 王智乐 吕文杰 徐彤 《饲料研究》 CAS 北大核心 2024年第16期40-45,共6页
试验旨在探讨胚蛋注射乳酸菌对蛋雏鸡孵化性能和肠道黏膜结构的影响。将150个SPF种蛋孵化至18胚龄时随机分成2组,每组3个重复,每个重复25个种蛋。对照组羊膜腔接种0.2 mL灭菌生理盐水,鸡胚乳酸菌注射组羊膜腔接种0.2 mL含1.21×10^(... 试验旨在探讨胚蛋注射乳酸菌对蛋雏鸡孵化性能和肠道黏膜结构的影响。将150个SPF种蛋孵化至18胚龄时随机分成2组,每组3个重复,每个重复25个种蛋。对照组羊膜腔接种0.2 mL灭菌生理盐水,鸡胚乳酸菌注射组羊膜腔接种0.2 mL含1.21×10^(8) CFU/mL活菌数的唾液乳杆菌XP132。孵化到21 d出壳,饲养期35 d。结果显示:胚蛋注射乳酸菌显著增加了蛋雏鸡体重(P<0.05)。与对照组相比,鸡胚乳酸菌注射组7日龄和28日龄的胸腺指数、14日龄脾脏指数和法氏囊指数、21日龄的胸腺指数和法氏囊指数均显著提高(P<0.05)。与对照组相比,鸡胚乳酸菌注射组雏鸡十二指肠绒毛高度(VH)显著提高(P<0.05),绒隐比(V/C)极显著升高(P<0.01);7日龄十二指肠隐窝深度(CD)极显著降低(P<0.01),21、35日龄十二指肠CD显著降低(P<0.05);7、21日龄空肠VH、V/C显著升高(P<0.05),CD显著降低(P<0.05);21日龄回肠VH显著升高(P<0.05),V/C极显著升高(P<0.01);35日龄回肠VH显著升高(P<0.05)。因饲养过程中未用抗生素,导致对照组部分雏鸡出现轻微细菌感染,电镜观察可见雏鸡十二指肠上皮细胞微绒毛、线粒体结构等细胞器出现了一定的损伤,而应用乳酸菌后7、21、35日龄雏鸡未出现细菌感染,上皮细胞微绒毛、线粒体结构和紧密连接蛋白等结构的损伤情况均得到改善。研究发现,胚蛋注射乳酸菌可增加SPF蛋鸡体重,并对其肠道黏膜结构具有一定的改善作用。 展开更多
关键词 胚蛋注射 鸡胚 乳酸菌 孵化率 体重 免疫器官指数 肠道黏膜结构
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电子超纯水制备过程典型痕量有机污染物去除机理
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作者 田宇鸣 熊江磊 +1 位作者 章洪斌 高康 《工业水处理》 CAS CSCD 北大核心 2024年第9期176-180,共5页
基于某12寸半导体超纯水中试线,对超纯水系统各处理单元总有机碳(TOC)去除过程及有机组分分子质量分布情况进行了跟踪检测,探究了有机碳紫外降解(TOC-UV)装置照射强度、水力停留时间和有机物分子键能对水中典型痕量有机污染物去除效果... 基于某12寸半导体超纯水中试线,对超纯水系统各处理单元总有机碳(TOC)去除过程及有机组分分子质量分布情况进行了跟踪检测,探究了有机碳紫外降解(TOC-UV)装置照射强度、水力停留时间和有机物分子键能对水中典型痕量有机污染物去除效果的影响。结果表明:两级反渗透(RO)系统可去除98.5%的TOC,一级RO产水中含有97.3%分子质量低于350 u的中性小分子物质;在一定范围内提升紫外光照射强度与水力停留时间可提升对小分子有机物的去除效果,2.46 mW/cm2的185 nm紫外灯对TOC去除效果最好,水力停留时间为40 s时TOC去除效率最佳;UV对有机物的降解效果明显受物质键能影响,TOC-UV对具有较高键能的小分子有机物(如尿素728 kJ/mol)的去除率较低。 展开更多
关键词 超纯水 总有机碳 TOC-UV 小分子有机物
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