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Isolation,Screening and Identification of Cellulose Decomposing Strains in Straw-amended Soil 被引量:3
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作者 郭艳 张进良 +2 位作者 王会平 齐辉 梁峰 《Agricultural Science & Technology》 CAS 2010年第4期134-137,147,共5页
[Objective]The aim was to isolate cellulose decomposing strains with high activity from straw-amended soil.[Method]Screening of CMC solid culture and shaking culture rescreening were carried out to obtain cellulose de... [Objective]The aim was to isolate cellulose decomposing strains with high activity from straw-amended soil.[Method]Screening of CMC solid culture and shaking culture rescreening were carried out to obtain cellulose decomposing strains with high activity from the corn straw amended soil,which were analyzed by 16rDNA sequence analysis.[Result]A bacterium and a fungus with higher endonucleases activity were obtained through preliminary screening and secondary screening,a fungus with higher filter paper enzyme activity,and a bacterium(NO.5 strain) with higher of both filter paper enzyme activity and CMC enzyme activity were obtained.The result of 16S rDNA sequence analysis showed that the similarity was 100% between NO.5 strain and Bacillus subtilis.[Conclusion]NO.5 strain was identified as Bacillus subtilis. 展开更多
关键词 Straw-amended soil Cellulose decomposing strains SCREENING CELLULASE
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Isolating and Screening of Effective Decomposing Strain of Silkworm Chrysalis Protein and Study on Parts of Its Enzymatic Properties 被引量:4
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作者 孔军 涂国全 +3 位作者 邝哲师 赵祥杰 叶明强 罗国庆 《Agricultural Science & Technology》 CAS 2010年第2期8-11,共4页
[Objective] The research aimed to obtain an effectively-decomposing strain of silkworm chrysalis protein and discuss its enzymatic properties.[Method] The effectively-decomposing bacteria of protein was isolated from ... [Objective] The research aimed to obtain an effectively-decomposing strain of silkworm chrysalis protein and discuss its enzymatic properties.[Method] The effectively-decomposing bacteria of protein was isolated from the decayed silkworm chrysalis by using dilution plate and its enzymatic properties were tested after primary screening and second screening.The enzyme activity was determined and the intermediate and small molecule protein content in silkworm chrysalis was measured after solid-state fermentati... 展开更多
关键词 decomposing strain of silkworm chrysalis Isolating and screening Neutral protease Enzymatic properties
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Screening on oil-decomposing microorganisms and application in organic waste treatment machine 被引量:9
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作者 LUYi-tong CHENXiao-bin ZHOUPei LIZhen-hong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期440-444,共5页
As an oil-decomposable mixture of two bacteria strains(Bacillus sp. and Pseudomonas sp.), Y3 was isolated after 50 d domestication under the condition that oil was used as the limited carbon source. The decomposing ra... As an oil-decomposable mixture of two bacteria strains(Bacillus sp. and Pseudomonas sp.), Y3 was isolated after 50 d domestication under the condition that oil was used as the limited carbon source. The decomposing rate by Y3 was higher than that by each separate individual strain, indicating a synergistic effect of the two bacteria. Under the conditions that T=25—40℃,pH=6—8, HRT(Hydraulic retention time)=36 h and the oil concentration at 0.1%, Y3 yielded the highest decomposing rate of 95.7 %. Y3 was also applied in an organic waste treatment machine and a certain rate of activated bacteria was put into the stuffing. A series of tests including humidity, pH, temperature, C/N rate and oil percentage of the stuffing were carried out to check the efficacy of oil-decomposition. Results showed that the oil content of the stuffing with inoculums was only half of that of the control. Furthermore, the bacteria were also beneficial to maintain the stability of the machine operating. Therefore, the bacteria mixture as well as the machines in this study could be very useful for waste treatment. 展开更多
关键词 oil-decomposing microorganism SCREENING application organic waste treatment machine decomposing rate
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Effect of alginic acid decomposing bacterium on the growth of Laminaria japonica (Phaeophyceae) 被引量:9
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作者 WANG You TANG Xue-xi +1 位作者 YANG Zhen YU Zhi-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第3期543-551,共9页
We collected the diseased blades of Larninaria japonica from Yantai Sea Farm from October to December 2002, and the alginic acid decomposing bacterium on the diseased blade was isolated and purified, and was identifie... We collected the diseased blades of Larninaria japonica from Yantai Sea Farm from October to December 2002, and the alginic acid decomposing bacterium on the diseased blade was isolated and purified, and was identified as A lteromonas espejiana. This bacterium was applied as the causative pathogen to infect the blades of L. japonica under laboratory conditions. The aim of the present study was to identify the effects of the bacterium on the growth of L. japonica, and to find the possibly effective mechanism. Results showed that: (1)The blades of L.japonica exhibited symptoms of lesion,bleaching and deteriortion when infected by the bacterium. and their growth and photosynthesis were dramatically suppressed. At the same time, the reactive oxygen species (ROS) generation enhanced obviously, and the relative membrane permeability increased significantly. The contents of malonaldehyde (MDA) and free fatty acid in the microsomol membrane greatly elevated, but the phospholipid content decreased. Result suggested an obvious peroxidation and deesterrification in the blades of L. japonica when infected by the bacterium. (2) The simultaneous assay on the antioxidant enzyme activities demonstrated that superoxide dismutase (SOD) and catalase (CAT) increased greatly when infected by the bacterium, but glutathione peroxidase (Gpx) and ascorbate peroxidase (APX) did not exhibit active responses to the bacterium throughout the experiment. (3) The histomorphological observations gave a distinctive evidence of the severity of the lesions as well as the relative abundance in the bacterial population on the blades after infection. The bacterium firstly invaded into the endodermis of L. japonica and gathered around there, and then resulted in the membrane damage, cells corruption and ultimately, the death of L. japonica. 展开更多
关键词 Laminaria japonica alginic acid decomposing bacterial INFECTION GROWTH MECHANISM
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Stimulatory effects of biosurfactant produced by Pseudomonas aeruginosa BSZ-07 on rice straw decomposing 被引量:7
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作者 ZHANG Qiuzhuo CAI Weimin WANG Juan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期975-980,共6页
Biosurfactant,produced by Pseudomonas aeruginosa BSZ-07,was added to the dee straw decomposing process to enhance the production of reducing sugars.Observed by Fourier Transform InfraRed(FT-IR)and Nuclear Magnetic Res... Biosurfactant,produced by Pseudomonas aeruginosa BSZ-07,was added to the dee straw decomposing process to enhance the production of reducing sugars.Observed by Fourier Transform InfraRed(FT-IR)and Nuclear Magnetic Resonance(NMR)analysis, the purified biosurfactant was considered as a mixture of RL1 and RL2,which are two different types of rhamnolipids.Two different adding methods,adding the purified rhamnolipid and the on-site production of it were compared.The results showed that 0.5 g/L was the optimum co... 展开更多
关键词 BIOSURFACTANT RHAMNOLIPID ON-SITE rice straw decomposing
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Preparation of nanostructure silver powders by mechanical decomposing and mechanochemical reduction of silver oxide 被引量:3
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作者 Gholam Reza KHAYATI Kamal JANGHORBAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第5期1520-1524,共5页
The mechanical decomposing and mechanochemical reductions of silver oxide for preparation of nanocrystalline silver powders by high planetary ball mill was investigated. XRD and HRSEM techniques were used to character... The mechanical decomposing and mechanochemical reductions of silver oxide for preparation of nanocrystalline silver powders by high planetary ball mill was investigated. XRD and HRSEM techniques were used to characterize the structural evolution and morphological changes of products. The results show that the nanostructured silver with an average crystallite size of 14 nm and internal strain of 0.75% is synthesized by mechanical decomposing of Ag2O after 95 h milling. While, the product of mechanochemical reduction of silver oxide using graphite after 22 h milling is nanostructured silver with an average crystallite size of 28 nm and internal strain of 0.44%. 展开更多
关键词 nanocrystalline silver silver oxide mechanical decomposing mechanochemical reduction
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An Approach for Improving Short-Term Prediction of Summer Rainfall over North China by Decomposing Interannual and Decadal Variability 被引量:2
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作者 HAN Leqiong LI Shuanglin LIU Na 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第2期435-448,共14页
A statistical downscaling approach was developed to improve seasonal-to-interannual prediction of summer rainfall over North China by considering the effect of decadal variability based on observational datasets and d... A statistical downscaling approach was developed to improve seasonal-to-interannual prediction of summer rainfall over North China by considering the effect of decadal variability based on observational datasets and dynamical model outputs.Both predictands and predictors were first decomposed into interannual and decadal components.Two predictive equations were then built separately for the two distinct timescales by using multivariate linear regressions based on independent sample validation.For the interannual timescale,850-hPa meridional wind and 500-hPa geopotential heights from multiple dynamical models' hindcasts and SSTs from observational datasets were used to construct predictors.For the decadal timescale,two well-known basin-scale SST decadal oscillation (the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation) indices were used as predictors.Then,the downscaled predictands were combined to represent the predicted/hindcasted total rainfall.The prediction was compared with the models' raw hindcasts and those from a similar approach but without timescale decomposition.In comparison to hindcasts from individual models or their multi-model ensemble mean,the skill of the present scheme was found to be significantly higher,with anomaly correlation coefficients increasing from nearly neutral to over 0.4 and with RMSE decreasing by up to 0.6 mm d-1.The improvements were also seen in the station-based temporal correlation of the predictions with observed rainfall,with the coefficients ranging from-0.1 to 0.87,obviously higher than the models' raw hindcasted rainfall results.Thus,the present approach exhibits a great advantage and may be appropriate for use in operational predictions. 展开更多
关键词 summer rainfall short-term prediction decomposing DOWNSCALING
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An initial study of insect succession on decomposing rabbit carrions in Harare,Zimbabwe 被引量:1
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作者 Nyasha Mabika Ron Masendu Gilbert Mawera 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第7期561-565,共5页
Objective:To investigate insects visiting sun exposed and shaded decomposing rabbit carcasses and to establish the relationship between insects and carcasses which may be of forensic importance in Harare.Methods:Two r... Objective:To investigate insects visiting sun exposed and shaded decomposing rabbit carcasses and to establish the relationship between insects and carcasses which may be of forensic importance in Harare.Methods:Two rabbits weighing 2.3 kg and 2.5 kg were killed by sharp blows on the head.One was exposed to the sun while the other was placed under shade.The carcasses were allowed to decompose and insects were collected twice a day for the first week and thereafter once a day up to the end of the 7 weeks.Maggots were also collected from the decomposing carcasses and reared.Results:Five dipteran families(Galliphoridae,Muscidae,Sarcophagidae,Phoridae and Drosophilidae)were identified from the sun-exposed carcass.Species collected included Lucilia cuprina(L.cuprina),Chrysomya albiceps(C.albiceps),Musca domestica,Sarcophaga sp.and Drosophila sp.Four families(Calliphoridae,Muscidae,Phoridae,Anthomyiidae)were identified from the shaded carcass.Representatives of these families included L cuprina,C.albiceps,Musca domestica,and Hydrotaea sp.Three Coleopteran families(Histeridae,Cleridae and Dermestidae)were identified from hodt carcasses.The observed species were Saprinus sp,Necrobia rufipes and Dermestes sp.Fomicidae(Hymenoptera)was represented by only one species(Pheidoie sp.)Flies which emerged from the rearing units were L cuprina,Lucilia sp.,C.albiceps,Sarcophaga sp.and Sepsis sp.).Conclusions:Of the dipteran species collected during the study,L cuprina and C.albiceps could be important for further forensic studies since they were collected from the carcasses and also observed from the rearing units. 展开更多
关键词 INSECT SUCCESSION Forensic ENTOMOLOGY decomposing RABBIT CARRION
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The effects of the environmental factors on Laminaria disease caused by alginic acid decomposing bacteria 被引量:1
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作者 Ding Meili Institute of Oceanology, Academia Sinica, Qingdao 266071, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第1期123-130,共8页
-The rot disease of Laminaria occurs often in nurseries of sporeling and commercial cultivation in the sea and results in economic loss greatly. Usually the disease outbreaks accompanied with massive multiplication of... -The rot disease of Laminaria occurs often in nurseries of sporeling and commercial cultivation in the sea and results in economic loss greatly. Usually the disease outbreaks accompanied with massive multiplication of alginic acid decomposing bacteria. From the section of the decaying Lamuutria which resulted from the inoculation of alginic acid decomposing bacteria, it was observed that the bacteria invaded the epiderm of the Laminaria surface at first, then entered the ex-odermis, endodermis and pith. In addition, there were a great amount of bacteria in the intercellular region and a lot of free cells of the algae in the decaying areas. The wall of some free cells was decomposed, which led to soft tissue or disintegration. Alginic acid decomposing bacteria are normal epiphytic microorganisms growing on Lamuutria surface. These bacteria do not cause disease at normal environmental conditions. The experiments showed that the unfavourable conditions, e. g. , wounding, overcrowding, high temperature reduced the ability of antibacterial activity and made the algae more susceptible to the pathogens and favoured the multiplication of alginic acid decomposing bacteria and finally led to the disease outbreak. The unfavourable environmental factors which resulted from a variety of reasons were the main cause of the disease. 展开更多
关键词 The effects of the environmental factors on Laminaria disease caused by alginic acid decomposing bacteria ACID
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Screening of cellulose decomposing fungi in sandy dune soil of Horqin Sandy Land
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作者 ShaoKun Wang XueYong Zhao +4 位作者 XiaoAn Zuo XinPing Liu Hao Qu Wei Mao JianYing Yun 《Research in Cold and Arid Regions》 CSCD 2015年第1期74-80,共7页
Cellulose decomposing fungi play an important role in litter decomposition and are decisive in nutrient cycling in sandy land ecosystems. Thirty-one strains were isolated to select efficient cellulose decomposers, and... Cellulose decomposing fungi play an important role in litter decomposition and are decisive in nutrient cycling in sandy land ecosystems. Thirty-one strains were isolated to select efficient cellulose decomposers, and four efficient cellulose decomposing fungi (NM3-1, NM3-2, NM3-3, and NM3-4) were screened using a CMC (carboxymethyl cellulose) carbon source in dune soil of Horqin Sandy Land. They were identified as Asperigillus calidoustus, Fusarium oxysporum, Fusarium solani, and Hypocrea lixii by rDNA-ITS molecular biological methods. Cloth decomposition rates were 15.71%, 15.89%, 17.29%, and 17.89% by the four efficient decomposers incubated for 30 days, respectively. Screening of efficient cellulose decomposers can not only increase the dune soil functional microbe bank, but can also accelerate litter decom- position and available nutrient input in the Horqin Sandy Land. 展开更多
关键词 cellulose decomposer SCREENING sandy dune soil decomposition ability Horqin Sandy Land
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Short-range structural change in indium melt by Gaussian peaks decomposing of RDF
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作者 SujuanCheng ZhonghuaWang 《Journal of University of Science and Technology Beijing》 CSCD 2002年第2期85-89,共5页
Liquid indium's structure was studied at 280, 390, 550, 650, and 750 deg Crespectively by using an elevated temperature X-ray diffractometer, and its radial distributionfunction (RDF) at different temperatures was... Liquid indium's structure was studied at 280, 390, 550, 650, and 750 deg Crespectively by using an elevated temperature X-ray diffractometer, and its radial distributionfunction (RDF) at different temperatures was decomposed into 4 Gaussian peaks in the range of0.2-0.6nm. Positions of the decomposed Gaussian peaks were compared with the nearest and the secondnearest neighbor atomic distances, respectively. It is shown that the position of the firstdecomposed Gaussian peak is similar to the nearest neighbor atomic distance in liquid In at thecorresponding temperature, and that of the third decomposed Gaussian peak is similar to the secondnearest neighbor atomic distance. Moreover, the first and the third Gaussian peaks correspond to thefirst and the second atom shells of liquid In at the corresponding temperatures, respectively.Therefore, the position and the area of Gaussian peaks can represent the position and atom number ofcorresponding shells. Based on this result, short-range structural changes in liquid In wasstudied. It was found that the first and the second shells are close to the referred atom, and theatom number at the shells decreases with the increasing temperature from 280 to 750 deg C. Indifferent ranges of temperature, structural changes in the first and the second shells showdifferent features. 展开更多
关键词 radial distribution function Gaussian peaks decomposing short-rangestructure atom shell
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Isolation and Identification of a Cellulose-Decomposing Fungal Strain
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作者 Xiang WU Bingcheng GAN +3 位作者 Dinghong JIA Liyuan XIE Yuanji JIANG Yong GUO 《Agricultural Biotechnology》 CAS 2013年第3期65-67,共3页
In this study, a cellulose-decomposing fungal strain was isolated from the fertile soil and named F18. The cultural characteristics and morphological characteristics of fungal strain F18 were investigated and its ITS ... In this study, a cellulose-decomposing fungal strain was isolated from the fertile soil and named F18. The cultural characteristics and morphological characteristics of fungal strain F18 were investigated and its ITS sequence was analyzed. According to the experimental results, fungal strain F18 belonged to Asper- g///us n/ger, which had ideal decomposing effect on cellulose and showed rapid and vigorous growth on a variety of medium. This study laid a preliminary foundation for the utilization of cellulose-decomposing fungal strain F18. 展开更多
关键词 CELLULOSE-decomposing F18 IDENTIFICATION Aspergillas niger
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森林凋落物分解速率的影响因素研究进展 被引量:2
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作者 郭屹立 刘绮 +2 位作者 陆雪干 刘铭 李先琨 《广西植物》 北大核心 2025年第3期413-425,共13页
凋落物作为森林生态系统的重要功能组成部分,其分解过程不仅是生态系统物质循环和能量流动的主要途径,还是构成生物地球化学循环的关键环节,深刻影响着土壤肥力、碳储存与释放以及生物多样性等多个方面,对维持生态平衡具有重要意义。该... 凋落物作为森林生态系统的重要功能组成部分,其分解过程不仅是生态系统物质循环和能量流动的主要途径,还是构成生物地球化学循环的关键环节,深刻影响着土壤肥力、碳储存与释放以及生物多样性等多个方面,对维持生态平衡具有重要意义。该文系统性地总结归纳了影响凋落物分解的主要因素,具体包括凋落物的化学组成、物理结构等质量特征,气候条件的变化,以及土壤分解者的种类与活性等。同时,该文还深入梳理了近些年来国内外在凋落物分解领域的研究进展和热点话题,这对深化森林生态系统管理、推动物质循环研究以及应对全球气候变化等都具有重要的理论与实践意义。未来研究应在整合不同森林生态系统的背景下,进一步深化对主场效应、土壤动物作用、光降解等话题的认识,并建立系统的分解机制研究框架。此外,构建一个针对全球气候变化背景下不同凋落物处理(包括添加与去除)的长期固定实验网络平台,对于深入揭示凋落物分解对土壤有机碳转化与稳定性机制具有重要意义。在全球气候变化的大背景下,该文为进一步探索凋落物分解过程的影响因素及其响应机制提供了生态学视角的见解与建议。 展开更多
关键词 森林生态系统 凋落物分解 凋落物质量 气候 土壤分解者
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秸秆还田配施腐熟剂及氮肥对土壤微生物资源限制及碳利用效率的影响 被引量:1
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作者 邹文秀 张乃文 +4 位作者 陈旭 严君 陆欣春 朱园辰 韩晓增 《植物营养与肥料学报》 北大核心 2025年第4期644-656,共13页
【目的】提高秸秆在土壤中的腐熟速度,有利于秸秆还田技术的推广和应用。探究腐熟剂配合氮肥施用情况下微生物资源限制及微生物碳利用效率的变化,以明确腐熟剂配施秸秆对土壤微生物代谢的影响机制,为农田秸秆腐熟剂的合理使用提供理论... 【目的】提高秸秆在土壤中的腐熟速度,有利于秸秆还田技术的推广和应用。探究腐熟剂配合氮肥施用情况下微生物资源限制及微生物碳利用效率的变化,以明确腐熟剂配施秸秆对土壤微生物代谢的影响机制,为农田秸秆腐熟剂的合理使用提供理论依据。【方法】采用室内培养试验,设置秸秆(S)、腐熟剂(D)、氮肥(N)及还田方式4个因素,具体处理包括:对照(CK),无添加;秸秆碎混(S);氮肥(N);秸秆碎混+氮肥(S+N);秸秆碎混+腐熟剂(S+D);秸秆碎混+氮肥+腐熟剂(S+N+D);秸秆尼龙袋填埋+氮肥+腐熟剂(SⅡ+N+D)。培养期为90天,于第30、60、90天进行破坏性取样,用电镜观测秸秆的纤维结构,分析土壤中微生物量碳、氮、磷含量(MBC、MBN、MBP)和酶活性,计算酶活性化学计量比。【结果】相比CK和S处理,培养60、90天时S+N+D处理秸秆表面结构出现大量孔洞。各处理下微生物量及相关胞外酶活性均随着培养时间延长呈先增加后降低的趋势,在最高活性时期(培养60天),S+N+D较S+D处理MBC、MBN和MBP含量分别显著增加了154.0%、55.0%和38.4%。SⅡ+N+D处理的土壤微生物生物量及酶活性显著低于S+N+D处理。根据土壤酶化学计量分析,各处理土壤均受碳、磷限制,最低土壤微生物碳限制出现在S+D(向量长度1.35±0.01)处理,最低磷限制出现在S+N+D(向量角度49.08°±1.42°)处理。除培养第30天外,S+N+D处理的微生物碳利用效率均较高,且微生物碳利用效率与微生物资源限制间呈显著负相关。【结论】腐熟剂与氮肥配合施用可显著增加土壤微生物生物量及酶活性,减缓秸秆带来的土壤微生物资源碳、磷限制,进而加速秸秆的分解,提高碳利用效率,因此,建议在实施秸秆还田措施时,配合施用秸秆腐熟剂和氮肥。 展开更多
关键词 腐熟剂 秸秆 氮肥 酶化学计量学 微生物碳利用效率
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Isolation and Identification of Cellulose- decomposing Bacteria from Deep-litter Systems
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作者 Qing LIAO Zepu JIANG +3 位作者 Ying XING Guangpo WEI Dongliang HUANG Yangrui LI 《Agricultural Biotechnology》 CAS 2015年第5期65-68,共4页
In this study, 43 cellulose-decomposing strains were isolated from deep-litter systems. After preliminary screening with Congo red identification medium and filter paper strip medium, five strains with large transpare... In this study, 43 cellulose-decomposing strains were isolated from deep-litter systems. After preliminary screening with Congo red identification medium and filter paper strip medium, five strains with large transparent circles that disintegrated filter paper strips were obtained. After further liquid fermentation, CMC activity, FPA activity and natural eellulase activity of these five strains were determined, and two cellulose-decomposing strains with higher enzyme activity were screened, which were named F7 and F21. Based on molecular biological identification and phylogenetic analysis of 16S rRNA gene sequences, these two cellulose- decomposing strains were identified as Bacillus subtilis and Streptomyces sp. , respectively. 展开更多
关键词 Deep-litter systems Cellulose-decomposing bacteria Screening 16S rDNA Identification
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电力设备中六氟化硫气体分解产物的化学检测和处理技术进展 被引量:3
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作者 张雯 贾钦相 +2 位作者 孙嘉鸿 牛飞宇 仵语盈 《化学工业与工程》 北大核心 2025年第1期78-87,共10页
六氟化硫(SF_(6))气体由于其优良的绝缘和灭弧性能被广泛应用于各类中高压电气设备中,但当设备内部存在微量的水和氧气等杂质时,SF_(6)会发生不同程度的分解并进一步生成各种复杂的产物。本论文从化学角度讨论分解产物的产生机理及常见... 六氟化硫(SF_(6))气体由于其优良的绝缘和灭弧性能被广泛应用于各类中高压电气设备中,但当设备内部存在微量的水和氧气等杂质时,SF_(6)会发生不同程度的分解并进一步生成各种复杂的产物。本论文从化学角度讨论分解产物的产生机理及常见的化学检测方法,对目前杂质气体的吸附处理、痕量检测和催化降解技术进行了综述,并对可能替代SF^(6)的新型绝缘气体进行了展望。 展开更多
关键词 SF6 分解产物 化学检测 杂质气体处理
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Comparative Research on Facultative Anaerobic Cellulose Decomposing Bacteria Screened from Soil and Rumen Content and Diet of Dairy Cow
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作者 Li Yan-fang Wang Lei +3 位作者 Liang Zi-chao Zhang Mei-mei Wang Jing-jing Liu Da-sen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第1期40-46,共7页
Twenty-nine facultative anaerobic cellulose-degrading bacteria were isolated from soil, rumen fluid, rumen residues and diet of dairy cow. Based on 16 Sr DNA analysis by BLAST algorithm method, the results showed that... Twenty-nine facultative anaerobic cellulose-degrading bacteria were isolated from soil, rumen fluid, rumen residues and diet of dairy cow. Based on 16 Sr DNA analysis by BLAST algorithm method, the results showed that most of the strains were Bacillus genera, and six of the 29 strains were bigger than 10 mm of diameter of clear zones. For them, two strains were isolated from rumen fluid(L5 and L7) and other two were isolated from rumen residue(N5 and N9), while others were isolated from soil(T1) and diet(S6), respectively. Strains from rumen fluid and residue had higher activities of FPCase and CMCase, but lower β-glucosidases. 展开更多
关键词 dairy cow facultative anaerobic cellulose-decomposing bacterium cellulase characteristic 16Sr DNA gene analysis
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风化花岗岩裂隙对盾构隧道衬砌地震易损性曲线的影响
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作者 张文杰 向平 +3 位作者 李英波 张飞宇 王志兵 于啸波 《世界地震工程》 北大核心 2025年第1期175-188,共14页
以穿越风化花岗岩地层的广州市轨道交通五号线盾构区间隧道为工程背景,建立裂隙-双隧道非线性时程分析模型,采用增量动力时程分析方法,探究裂隙角度、长度及注浆填充组合工况下的隧道衬砌易损性曲线的变化规律。采用弯矩比作为衬砌损伤... 以穿越风化花岗岩地层的广州市轨道交通五号线盾构区间隧道为工程背景,建立裂隙-双隧道非线性时程分析模型,采用增量动力时程分析方法,探究裂隙角度、长度及注浆填充组合工况下的隧道衬砌易损性曲线的变化规律。采用弯矩比作为衬砌损伤指标,采用地表峰值加速度和地表峰值速度作为地震强度指标,得到隧道衬砌的易损性曲线,阐明裂隙对隧道衬砌的抗震性能影响。结果表明:衬砌损伤概率会随裂隙在震动方向上投影长度增大而提高;衬砌损伤概率与裂隙长度呈正相关关系;对裂隙进行C25砂浆填充之后,隧道衬砌的地震损伤概率降低,表明工程实践中对裂隙进行填充的操作既可以提高围岩静稳定性,也可以提高隧道衬砌抗震性能。节理裂隙对围岩的局部劣化作用导致隧道衬砌地震损伤概率增加,效果与隧道场地剪切波速降低后相近。 展开更多
关键词 盾构隧道 地震响应 地震易损性 裂隙 风化花岗岩
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六味地黄汤及拆方对小鼠黑色素瘤B16细胞胸苷激酶/更昔洛韦自杀基因疗法旁观者效应的影响
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作者 赵婷秀 潘啟暘 +5 位作者 孙渊 王幸鹏 刘坤东 吴绍锋 杜标炎 吴彤 《环球中医药》 2025年第3期405-412,共8页
目的观察六味地黄汤及拆方对小鼠黑色素瘤B16细胞胸苷激酶(herpes simplex virus-thymidine kinase,HSV-tk)/更昔洛韦(ganciclovir,GCV)自杀基因疗法旁观者效应的作用机制及配伍规律。方法实验动物分对照组、GCV组、GCV+六味组、GCV+三... 目的观察六味地黄汤及拆方对小鼠黑色素瘤B16细胞胸苷激酶(herpes simplex virus-thymidine kinase,HSV-tk)/更昔洛韦(ganciclovir,GCV)自杀基因疗法旁观者效应的作用机制及配伍规律。方法实验动物分对照组、GCV组、GCV+六味组、GCV+三补组、GCV+三泻组。采用小鼠双侧腋下分别移植B16-tk细胞和B16细胞、腹腔注射GCV的方法,建立小鼠黑色素瘤B16细胞HSV-tk/GCV自杀基因移植瘤模型。对照组腹腔注射生理盐水。各组给予相应药物灌胃给药14天,观察六味地黄汤及拆方对B16肿瘤的旁观者效应。ELISA法检测B16肿瘤和脾脏的IL-2浓度;观察B16肿瘤和脾脏的淋巴细胞分布情况。结果与对照组比较,各组B16-tk肿瘤生长均显著抑制。与GCV组比较,GCV+六味组和GCV+三补组B16肿瘤的生长明显抑制、肿瘤系数显著减少(P<0.01),IL-2浓度明显升高(P<0.01)、淋巴细胞浸润明显,其中,GCV+六味组CD_(8)^(+)T细胞浸润明显,GCV+三补组CD_(4)^(+)T细胞浸润明显;脾脏的IL-2浓度明显降低(P<0.01)、CD_(8)^(+)T细胞增多。而GCV+三泻组的B16肿瘤生长加速,肿瘤系数增加,肿瘤IL-2明显降低(P<0.01),肿瘤组织充血和出血明显,未见淋巴细胞浸润;脾脏IL-2明显升高(P<0.01)、未见CD_(8)^(+)T细胞。结论六味地黄汤可以明显增效小鼠黑色素瘤B16细胞HSV-tk/GCV自杀基因疗法旁观者效应,其机制可能与改善肿瘤和脾脏的IL-2浓度以及淋巴细胞数量有关,增效的主要物质在三补成分,而三泻成分拮抗旁观者效应。 展开更多
关键词 六味地黄汤 拆方 黑色素瘤 自杀基因疗法 旁观者效应
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还田方式对玉米秸秆腐解特征及其节肥潜力的影响 被引量:7
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作者 刘熙明 袁静超 +5 位作者 梁尧 刘剑钊 任军 高强 冯国忠 蔡红光 《农业资源与环境学报》 北大核心 2025年第2期404-411,共8页
本研究通过在黑土区设置还田方式和还田量双因素秸秆腐解模拟试验,探讨不同秸秆还田方式影响下秸秆腐解特征与养分释放动态,为秸秆资源的高效利用提供理论依据。试验地点位于吉林省四平市典型黑土区,设置尼龙网袋法模拟覆盖(Straw mulch... 本研究通过在黑土区设置还田方式和还田量双因素秸秆腐解模拟试验,探讨不同秸秆还田方式影响下秸秆腐解特征与养分释放动态,为秸秆资源的高效利用提供理论依据。试验地点位于吉林省四平市典型黑土区,设置尼龙网袋法模拟覆盖(Straw mulching)和深翻(Straw burying)2种还田方式和半量还田(50%,R1)、减量还田(75%,R2)、全量还田(100%,R3)3种还田量互作处理,于2021—2022年动态采集网袋秸秆样品分析其腐解特征与养分释放动态,估算不同还田模式下秸秆节肥潜力。结果表明,在黑土区,深翻还田和减量还田结合下秸秆腐解与养分释放程度最高,腐解率达到87.7%,碳、氮、磷、钾释放率达到67.5%、78.3%、82.4%和97.2%。与覆盖还田相比,深翻还田秸秆腐解率平均增加15.0个百分点,秸秆碳、氮、磷、钾释放率平均增加16.7、18.0、15.4个和1.5个百分点。不同还田量处理中减量还田对秸秆腐解和碳、氮、磷的释放具有明显促进作用,但对秸秆钾的释放影响不显著。深翻还田和全量还田秸秆养分累积释放量最高,秸秆碳、氮、磷、钾累积释放量分别为2500.1、54.9、5.7 kg·hm^(-2)和121.2 kg·hm^(-2)。还田秸秆对氮肥和钾肥的替代潜力较高,对磷肥的替代潜力较低。研究表明,因地制宜采用不同秸秆还田方式、科学配置秸秆资源、结合作物养分需求合理施肥,是提高资源利用效率和生态效益、实现绿色生产的重要途径。 展开更多
关键词 还田方式 还田量 腐解特征 养分释放
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