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浅谈书画装裱技术 被引量:2
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作者 周景华 《兰台世界(上旬)》 1994年第5期26-27,共2页
浅谈书画装裱技术辽宁省档案馆周景华书画装待艺术是我国的一种传统的装璜工艺。俗话说:三分画、七分裱。通过装裱与画相互辉映,浑然一体,使作品更臻完美。近年来,书画艺术也逐渐走入了平民百姓的家。为使装校艺术真正被人们所认识... 浅谈书画装裱技术辽宁省档案馆周景华书画装待艺术是我国的一种传统的装璜工艺。俗话说:三分画、七分裱。通过装裱与画相互辉映,浑然一体,使作品更臻完美。近年来,书画艺术也逐渐走入了平民百姓的家。为使装校艺术真正被人们所认识,拟作以简要介绍。我国传统的书画装... 展开更多
关键词 书画装裱 平民百姓 书画艺术 景华 复背 飞托 折一 品式 地杆
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超重梁模板支撑体系的施工要点 被引量:1
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作者 陈方丽 《中华建设》 2017年第3期120-121,共2页
随着高层建筑、大跨度建筑的数量逐渐增多,为了起到良好的空间作用,设计中涉及了众多超高、超大的混凝土结构。这种结构虽然给建筑的应用方面带来一定优势,但是对施工中板支撑体系增添了难度。一、超重梁模板支撑系统概述1.模版(1)梁... 随着高层建筑、大跨度建筑的数量逐渐增多,为了起到良好的空间作用,设计中涉及了众多超高、超大的混凝土结构。这种结构虽然给建筑的应用方面带来一定优势,但是对施工中板支撑体系增添了难度。一、超重梁模板支撑系统概述1.模版(1)梁、板之间采用的、模版通常是厚度为1.8厘米的胶合板,在选择木龙骨时,通常采用6*8厘米的木方,木方和夹层板接触面以及对面需要保证平行, 展开更多
关键词 模板支撑体系 混凝土结构 大跨度建筑 水平 剪刀撑 高层建筑 地杆 模板支撑系统 木方 架体
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Analysis on 16S-ITS Marker from Bacillus licheniformis and Its Specificity
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作者 陈冲 佟建明 张潞生 《Agricultural Science & Technology》 CAS 2011年第11期1572-1573,1588,共3页
[Objective] This study aimed to establish molecular identification methods for Bacillus licheniformis. [Method] Based on clone sequencing and difference analysis for 16S and ITS sequences of B. licheniformis TS-01, sp... [Objective] This study aimed to establish molecular identification methods for Bacillus licheniformis. [Method] Based on clone sequencing and difference analysis for 16S and ITS sequences of B. licheniformis TS-01, specific primers were designed using region sequences as the targets used for amplifying all test strains. [Result] The specific primers of B. licheniformis were designed from the ITS and 16S rDNA regions. The optimal annealing temperature of the specific primers for PCR was 67.2 ℃ with 24 cycles. A 905 bp marker fragment was amplified for B. licheniformis TS-01, while all other test strains showed negative results. This indicated that a specific 16S-ITS marker was obtained, which accurately identified the strain at the species level. [Conclusion] This molecular identification method for B. licheniformis TS-01 has laid the foundation for molecular diagnosis of B. licheniformis. 展开更多
关键词 Bacillus licheniformis Specific primer 16S ITS
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装载机新附具——推柴板
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作者 丁攀 《工程机械与维修》 2015年第6期81-,共1页
随着农业规模化生产的发展,装载机在农牧业上的用途越来越多,为满足各种形式农牧生产,除了简单的装运物料外,装载机配套附具的越来越多。我们发现农作物采摘后,农田中的残余枝干很多,如棉花田堆积繁多地杆茎,人力清除工作量繁重。为此... 随着农业规模化生产的发展,装载机在农牧业上的用途越来越多,为满足各种形式农牧生产,除了简单的装运物料外,装载机配套附具的越来越多。我们发现农作物采摘后,农田中的残余枝干很多,如棉花田堆积繁多地杆茎,人力清除工作量繁重。为此我公司设计生产的一种推柴附具一推柴板。该推柴板与装载机采用挂钩销轴式快换装置,其安装方法如下:首先,将装载机铲斗拆下,装上快换托架;其次,开动装载机,用快换托架的销轴挂住推柴板上的快换挂钩。 展开更多
关键词 棉花田 销轴 地杆 轴式 销孔 东风西路 美洲地区 板体 机械图 作者地址
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施工现场常用工具(脚手架)的安全操作
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《重庆建筑》 2017年第8期36-36,共1页
1.材料把控钢管表面应平直光滑,无裂缝、结疤、分层、错位、硬弯、毛刺、压痕等,钢管上严禁打孔,须涂防锈漆。宜采用48mm×3.5mm的钢管。扣件式钢管脚手架应采用可锻铸铁制作的扣件。2.基础把控脚手架立杆基础须平整、夯实,立杆底... 1.材料把控钢管表面应平直光滑,无裂缝、结疤、分层、错位、硬弯、毛刺、压痕等,钢管上严禁打孔,须涂防锈漆。宜采用48mm×3.5mm的钢管。扣件式钢管脚手架应采用可锻铸铁制作的扣件。2.基础把控脚手架立杆基础须平整、夯实,立杆底部设底座和垫板,距地面200 mm处设纵横向扫地杆。 展开更多
关键词 常用工具 施工现场 地杆 剪刀撑 水平 密目式安全网 脚手板 压痕 挡脚板 侧立面
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Epidemiological Investigation of Actinobacillus Pleuropneumoniae in Western Shandong 被引量:4
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作者 徐公义 王海丽 葛长城 《Agricultural Science & Technology》 CAS 2009年第4期141-145,共5页
[ Objective ] The aim of this study was to investigate the epidemic status of porcine pleuropneumonia in western Shandong and establish the PCR method of actinobacillus pleuropneumoniae (APP). [ Method] The epidemic... [ Objective ] The aim of this study was to investigate the epidemic status of porcine pleuropneumonia in western Shandong and establish the PCR method of actinobacillus pleuropneumoniae (APP). [ Method] The epidemic status of APP in lesion tissues of 186 death pigs and 545 health pigs without clinical symptoms was analyzed by PCR method. [ Result] APP positive rate in 186 samples accounted for 43.0% (80/186), while that in 545 porcine serums accounted for 9.4% (51/545). [ Conclusion] This PCR method can be used as one of the important means for APP clinical diagnosis. 展开更多
关键词 Actinobacillus pleuropneumoniae PCR DETECTION
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Hydrogeochemical modelling of corrosive environment contributing to premature failure of anchor bolts in underground coal mines 被引量:2
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作者 PENG Ya Wendy TIMMS 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1599-1610,共12页
Anchor bolts are commonly used throughout underground mining and tunnelling operations to improve roof stability.However,premature failures of anchor bolts are significant safety risks in underground excavations aroun... Anchor bolts are commonly used throughout underground mining and tunnelling operations to improve roof stability.However,premature failures of anchor bolts are significant safety risks in underground excavations around the world due to susceptible bolt materials,a moist and corrosive environment and tensile stress.In this paper,laboratory experiments and hydrogeochemical models were combined to investigate anchor bolt corrosion and failure associated with aqueous environments in underground coal mines.Experimental data and collated mine water chemistry data were used to simulate bolt corrosion reactions with groundwater and rock materials with the PHREEQC code.A series of models quantified reactions involving iron and carbon under aerobic and anaerobic conditions in comparison with ion,pH and pE trends in experimental data.The models showed that corrosion processes are inhibited by some natural environmental factors,because dissolved oxygen would cause more iron from the bolts to oxidize into solution.These interdisciplinary insights into corrosion failure of underground anchor bolts confirm that environmental factors are important contributors to stress corrosion cracking. 展开更多
关键词 anchor bolts hydrogeochemical modelling rock bolts and cable bolts stress corrosion cracking water chemistry analysis
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Anchoring effect and energy-absorbing support mechanism of large deformation bolt 被引量:12
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作者 ZHAO Tong-bin XING Ming-lu +2 位作者 GUO Wei-yao WANG Cun-wen WANG Bo 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第2期572-581,共10页
To research the anchoring effect of large deformation bolt,tensile and drawing models are established.Then,the evolution laws of drawing force,bolt axial force and interfacial shear stress are analyzed.Additionally,th... To research the anchoring effect of large deformation bolt,tensile and drawing models are established.Then,the evolution laws of drawing force,bolt axial force and interfacial shear stress are analyzed.Additionally,the influence of structure element position on the anchoring effect of large deformation bolt is discussed.At last,the energy-absorbing support mechanism is discussed.Results show that during the drawing process of normal bolt,drawing force,bolt axial force and interfacial shear stress all gradually increase as increasing the drawing displacement,but when the large deformation bolt enters the structural deformation stage,these three values will keep stable;when the structure element of large deformation bolt approaches the drawing end,the fluctuation range of drawing force decreases,the distributions of bolt axial force and interfacial shear stress of anchorage section are steady and the increasing rate of interfacial shear stress decreases,which are advantageous for keeping the stress stability of the anchorage body.During the working process of large deformation bolt,the strain of bolt body is small,the working resistance is stable and the distributions of bolt axial force and interfacial shear stress are steady.When a rock burst event occurs,the bolt and bonding interface cannot easily break,which weakens the dynamic disaster degree. 展开更多
关键词 rock burst large deformation bolt numerical simulation pull-out test anchoring effect energy-absorbing mechanism
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Spherical pattern of tide-isostasy model and its application 被引量:3
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作者 YANGDong-hong WANGYe YANGXue-xiang 《Journal of Geoscientific Research in Northeast Asia》 2004年第2期188-195,共8页
In this paper, a calculation formula on spherical pattern of tide-isostasy model is established. The calculation indicated that for the oceanic crust plate which central angle is over 90°, a huge value(its equiva... In this paper, a calculation formula on spherical pattern of tide-isostasy model is established. The calculation indicated that for the oceanic crust plate which central angle is over 90°, a huge value(its equivalence is 108 N)of accumulative force moment in the crustal isostatic movement caused by tide can trigger off relative motion of plate, resulting in earthquake and volcanic eruption. The seismic wave features during the year 2001-2004 is an obvious example. The paracycles, i.e. 4, 12, 60, 36, 243, 372 and 396 years of tidal fluctuation can provide an explanation for some respective natural disasters. For example, La Madre paracycle about 60 years corresponds to the global disasters,earthquake and typhoon disasters. 展开更多
关键词 tide-isostasy model seesaw motion Pacific Decade Oscillation earthquake TYPHOON
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Helicobacter pylori vacA s1a and s1b alleles from clinical isolates from different regions of Chile show a distinct geographic distribution 被引量:1
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作者 MI Díaz A Valdivia +14 位作者 P Martínez JL Palacios P Harris J Novales E Garrido D Valderrama C Shilling A Kirberg E Hebel J Fierro R Bravo F Siegel G Leon G Klapp A Venegas 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第40期6366-6372,共7页
AIM: To establish the most common vacA alleles in Helicobacter pylori ( H pylon) strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers, METHODS: Two hundred and forty... AIM: To establish the most common vacA alleles in Helicobacter pylori ( H pylon) strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers, METHODS: Two hundred and forty five Hpyloriclinical isolates were obtained from 79 biopsies from Chilean infected patients suffedng from gastrointestinal diseases. An average of 2-3 strains per patient was isolated and the vac4 genotype was analyzed by PCR and 3% agarose electrophoresis. Some genotypes were checked by DNA sequencing. RESULTS: The most prevalent vacA genotype in Chilean patients was slb ml (76%), followed by sla ml (21%). In oontrast, the s2 m2 genotype was scarcely represented (3%). The slb ml genotype was found most frequently linked to gastropathies (P〈0.05) rather than ulcers. Ulcers were found more commonly in male and older patients. Curiously, patents IMng in dties located North and far South of Santiago, thecapital and largest Chilean city, carried almost exclusively strains with the slb ml genotype. In contrast, patients from Santiago and cities located South of Santiago carded strains with either one or both sla ml and slb ml genotypes. Regarding the s2 m2 genotype, comparison with GenBank sequences revealed that Chilean s2 sequence was identical to those of Australian, American, and Colombian strains but quite different from those of Alaska and India. CONCLUSION: Differences in geographic distribution of the s and m vacA alleles in Chile and a relationship of slb ml genotype with gastritis were found. Sequence data in part support a hispanic origin for the vacA genotype. Asymmetric distribution of genotypes slb ml and s2 m2 recedes H Pyloristrain distribution in Spain and Portugal. 展开更多
关键词 Hpylori vacA alleles Chilean isolates s1 s2 m1 and m2 sequences
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Production of Alkaline Protease by Bacillus Licheniformis 被引量:1
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作者 Bahareh Sadeghein Seyed Abolhasan Alavi 《Journal of Chemistry and Chemical Engineering》 2011年第2期105-109,共5页
In this research the results of studies on optimization of alkaline protease production by Bacillus licheniformis are reported. The parameters, which were taken into consideration, are pH, temperature, time course of ... In this research the results of studies on optimization of alkaline protease production by Bacillus licheniformis are reported. The parameters, which were taken into consideration, are pH, temperature, time course of enzyme production, stirring rate and kinetics parameters. The effect of various carbon and nitrogen sources in culture medium compound on enzyme production was also considered The result of optimization revealed that maximum protease production was obtained at 37 ℃, pH equivalent tol 0.0 and with 150 rpm will occur after 72 hours. By comparing the effect of 5 carbon sources (maltose, glucose, starch, casein and lactose) in enzyme production, it has been known that using lactose will increase about 1.5 times enzyme production, compared to condition in which maltose is used. The result of studies on the effect of five nitrogen sources (i.e., peptone, tryptone, ammonium sulfate, urea and corn steep liquor) shows that corn steep liqour increases enzyme production more than others, while peptone can also be considered as a good nitrogen source; but, ammonium sulfate and urea reduce enzyme production considerably. It was concluded that protease production occurs in the stationary phase of growth. Studying the kinetics parameters resulted that the best model for the enzyme above is Lineweaver-Burk model according to which Km is 0.64 mmol and Vmax is 88 lamol/min. 展开更多
关键词 Bacillus licheniformis PRODUCTION ENZYME alkaline protease
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Characteristics of stress distribution in floor strata and control of roadway stability under coal pillars 被引量:9
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作者 Tongqiang Xiao Bai Jianbiao +1 位作者 Xu Lei Zhang Xuebin 《Mining Science and Technology》 EI CAS 2011年第2期243-247,共5页
Given the difficulties encountered in roadway support under coal pillars,we studied the characteristics of stress distribution and their effect on roadway stability,using theoretical analysis and numerical simulation.... Given the difficulties encountered in roadway support under coal pillars,we studied the characteristics of stress distribution and their effect on roadway stability,using theoretical analysis and numerical simulation.The results show that,under a coal pillar,vertical stress in a floor stratum increases while horizontal stress decreases.We conclude that the increased difference between vertical and horizontal stress is an important reason for deformation of the surrounding rock and failures of roadways under coal pillars.Based on this,we propose control technologies of the surrounding rock of a roadway under a coal pillar,such as high strength and high pre-stressed bolt support,cable reinforcement support single hydraulic prop with beam support and reinforcement by grouting of the surrounding rock,which have been successfully applied in a stability control project of a roadway under a coal pillar. 展开更多
关键词 Close-distance seams Coal pillar Stress distribution Roadway layout Surrounding rock control
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Utilization of low quality water of mountain reservoirs: a case study from Al Jabal Al Akhdar, Oman
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作者 Mushtaque AHMED Reginald VICTOR +1 位作者 Mohammed JASHOUL B.S. CHOUDRI 《Journal of Mountain Science》 SCIE CSCD 2016年第8期1423-1430,共8页
Al Jabal al Akhdar(Green Mountain) in arid northern Oman has freshwater resources that had supported small communities for hundreds of years. Jabal Akhdar receives more rainfall(300-400 mm) when compared to the desert... Al Jabal al Akhdar(Green Mountain) in arid northern Oman has freshwater resources that had supported small communities for hundreds of years. Jabal Akhdar receives more rainfall(300-400 mm) when compared to the desert plains. In the last few years, this region had undergone enormous changes due to rapid development. The resident and transient populations have increased and their activities exert severe stress on the water resources. There are 24 retention reservoirs in the area, but most are eutrophic and the nutrient loading is due to input of animal fecal matter via surface run-off. As expected, these waters contaminated with coliform bacteria and some have pathogenic Escherichia coli. Drinking water needs of all the villages met by groundwater extraction. Because of poor quality, the surface water in the reservoirs is under-utilized. A low-cost lowmaintenance treatment system designed, constructed and operated in one village to clean the reservoir water for non-drinking human use. The treatment unit improved the water quality parameters. A survey among the adult male population of the village showed their eagerness to adopt this system and use the treated reservoir water for uses other than agriculture. Establishment of these treatment units in other villages should reduce the pressures on groundwater extraction. 展开更多
关键词 Jabal Akhdar Oman RESERVOIR EUTROPHICATION Treatment SOCIETY
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Identification and Physiological Properties of Bifidobacterium Strains Isolated from Different Origin
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作者 Fatima Mahmoudi Hadadji Miloud Guessas Bettache Kihal Mebrouk 《Journal of Food Science and Engineering》 2013年第4期196-206,共11页
Bifidobacteria play an important role in maintaining human health, and suppress harmful bacteria by controlling the pH of the large intestine. About 14 strains of the Bifidobacteria have been isolated from the faeces ... Bifidobacteria play an important role in maintaining human health, and suppress harmful bacteria by controlling the pH of the large intestine. About 14 strains of the Bifidobacteria have been isolated from the faeces of infants nursed exclusively from the maternal milk (their ages less than 5 months) from commercial French yoghurt (active bifidus] and from milk (celia bifidus) on MRS medium (containing 0.05% cysteine-HC1, with nalidixic acid 2 mg rel). A total of six strain are strict anaerobic and gram-positive Bifidobacteria, identified as, B. longum (60% of the samples) was the most frequently found species, followed by B. bifidum (21.0%), B. breve (19%). These strains were evaluated for potential use as probiotics based on their adhesion to intestinal epithelial cells, resistance towards acidic (resistance to low pH) and bile conditions, pH values ranging from 6.5 to 7, however, these strains are sensitive to the pH 8, Bifidobacterium are mesophiles with optimal growth at 36℃ to 41℃. All isolates studied have a fast growth in glucose. 展开更多
关键词 Probiotic BIFIDOBACTERIUM ACIDITY SURVIVAL growth ISOLATE
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Bacillus Licheniformis Dhs-40, a Flocculating Active Strain and Its Flocculating Activity
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作者 Y.S. Zhang J. Wang J.A. Hao X.Z. Zhang Y. Cheng 《Journal of Environmental Science and Engineering》 2010年第5期53-59,共7页
Microbial flocculants have become a hot spot in recent years. A bacterial strain with high flocculating activity was isolated from seawater samples. The strain was defined as Bacillus licheniformis dhs-40 by 16S rDNA ... Microbial flocculants have become a hot spot in recent years. A bacterial strain with high flocculating activity was isolated from seawater samples. The strain was defined as Bacillus licheniformis dhs-40 by 16S rDNA identification and Biolog test. Ultrasonication test confirmed the flocculating activity of the strain was both in fermentation supernatant and cell. According to flocculating activity curve, the ideal fermentation time for collecting flocculating active substances was two days. The flocculating activity of the strain was sensitive to pH. The strain could only preserve flocculating activity while pH varied from 7 to 11. However, it could preserve flocculating activity while temperature varied from -20℃to 100 ℃ Saccharide, protein, lipid, nucleic acids qualitative test and RNase, Proteinase K treatment confirmed the flocculating active substances were proteins. Their flocculating activities were insensitive to Proteinase K. 展开更多
关键词 Flocculating activity bacteria isolation and identification active substances.
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Establishment of Kinetics Models for Batch Fermentation Process of β-mannase with Bacillus licheniformis HDYM-04
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作者 Chao PAN Xing XIN +8 位作者 Dan ZHAO Dongni GAO Xiaohang ZHOU Xue TIAN Xin XIE Jingping GE Hongzhi LING Gang SONG Wenxiang PING 《Agricultural Science & Technology》 CAS 2014年第5期779-784,共6页
In order to improve the yield of β-mannase and to investigate the rules of fermentation production, a high-yield β-mannase producing strain, Bacillus licheniformis HDYM-04, was used to investigate the kinetics model... In order to improve the yield of β-mannase and to investigate the rules of fermentation production, a high-yield β-mannase producing strain, Bacillus licheniformis HDYM-04, was used to investigate the kinetics models based on the optimal fermentation conditions: HDYM-04 strain was fermented at 37℃ for 30 h with agitation speed at 300 r/min and aeration rate at 3 L/min in a 5 L fermenter, the initial addition amount of konjac flour was 2%(w/v), the initial pH of medium was 8.0, and the inoculum concentration was 6.7%(v/v). Three batch fermentation kinetic models were established (cell growth kinetic model, substrate consumption kinetic model, product formation kinetic model) bases on Logistic and Luedeking-Piret equations. To be specific, cell growth kinetic model was dX/dt =0.431X (1- X/ 15.522 ), substrate consumption kinetic model was -ds/dt =1.11 dX/dt +0.000 2 dP/dt +0.000 8X, and product formation kinetic model was dP/dt=133.1 dX +222.87X. The correlation coefficients R^2 of the three equations were 0.990 21, 0.989 08 and 0.988 12, respectively, which indicated a good correlation between experimental values and models. Therefore, the three equations could be used to describe the processes of cell growth, enzyme synthesis and substrate consumption during batch fermentation using B. licheniformis strain HDYM-04. The establishment of batch fermentation kinetic models (cell growth kinetic model, substrate depletion kinetic model, product formation kinetic model) could lay the theoretical foundation and provide practical reference for the applica- tion of HDYM-04 in fermentation industry. 展开更多
关键词 Bacillus licheniformis Β-MANNANASE Fermentation kinetics Batch fermentation
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Study on mechanical principle of reinforcing sidewalls and corners of roadway to control floor heave by anchors 被引量:3
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作者 王卫军 《Journal of Coal Science & Engineering(China)》 2003年第1期17-21,共5页
The movement principle of sidewalls and floor of extraction opening is analyzed, it is found that floor heave not only has something to do with the floor strata, but sidewalls. The effect of sidewall anchor and corner... The movement principle of sidewalls and floor of extraction opening is analyzed, it is found that floor heave not only has something to do with the floor strata, but sidewalls. The effect of sidewall anchor and corner anchor is studied, the mechanical principle of reinforcing sidewalls and corners is put forward and applied in engineering practice. 展开更多
关键词 sidewalls and corners anchor reinforcing floor heave control mechanical principle
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Parameters determination and bolting control of gateway floor 被引量:1
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作者 GOU Pan-feng XIN Ya-jun 《Journal of Coal Science & Engineering(China)》 2011年第4期388-392,共5页
Gateway floor heave control is the key to guarantee mine safe and efficient production. Through analysis of floor instability characteristics and bolting control, gateway floor strata show second level stress under ab... Gateway floor heave control is the key to guarantee mine safe and efficient production. Through analysis of floor instability characteristics and bolting control, gateway floor strata show second level stress under abutment pressure, which causes plastic flow failure in floor strata; gateway floor instability shows mainly shear-break slippage of "triangle sliding body". Mechanics of floor bolting is mainly a function of connection and combination. Main area of bolting control lies in two gateway floor angles. The paper analyzes mechanics principle of gateway floor instability, constructs stability mechanics model of gateway floor bolting, obtains gateway floor stability criterion of different bolting angles and optimum formula of bolting parameters, carries out the engineering example, and guides better field application. It provides theoretical base for bolting gateway floor instability control. 展开更多
关键词 parameter determination BOLTING gateway floor heave mechanical model judge criterion
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Retreived bacteria from Noctiluca miliaris (green) bloom of the northeastern Arabian Sea
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作者 BASU Subhajit MATONDKAR SG Prabhu FURTADO Irene 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期10-20,共11页
In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea (NAS). This study provides the first characterization of bacteria from a seasona... In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea (NAS). This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca ofNAS (20°N-17°N and 64°E-70°E), during the spring-inter-monsoon cruise ofSagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number (MPN) and plate counts, revealed 'variable-physiotypes' over a wide range of salinities (0%-25% w/v NaC1), pH levels (5-8.5), and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations *DWK and *PRB, corresponded to (3.08-4.41)×103 cells/mL at 3.5% NaC1 (w/v), and (2.82-9.49)× 102 cells/mL at 25% (w/v) NaC1 in tryptone-yeast extract broth (TYE). Plate counts were (1.12-4) × 106 CFU/mL at 0% (w/v) NaC1, (1.28-3.9) × 106 CFU/mL at 3.5% (w/v) NaC1, and (0.4- 7)×104 CFU/mL at 25% NaC1 (w/v) on TYE. One-tenth-strength Zobell's gave (0.6-3.74)× 105 CFU/mL at pH 5 to (3.58-7.5)× 105 CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Diergibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains (GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84) was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillusflexus, and Bacillus cereus. The -2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation. 展开更多
关键词 northeastern Arabian Sea (NAS) green Noctiluca bloom retrievable bacteria
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Contamination of Groundwater Sources with Common Waterborne Pathogens and Heficobacter pylori in the West Bank: Case Study of Wadi AI Arroub, Tulkarem and Jericho
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作者 Maysa Azzeh Linda Atteyeh Amer Marei 《Journal of Environmental Science and Engineering(B)》 2014年第4期210-217,共8页
Detection of waterborne pathogens in drinking water via rapid DNA amplification assays is an important and crucial public health method. The aim of this study is to investigate the presence of waterborne pathogens in ... Detection of waterborne pathogens in drinking water via rapid DNA amplification assays is an important and crucial public health method. The aim of this study is to investigate the presence of waterborne pathogens in groundwater resources in Al Arroub, Tulkarem and Jericho areas using direct PCR (polymerase chain reaction) analysis. Forty-six groundwater samples were collected. The total DNA was extracted from each sample and subjected to PCR analysis directed to specific genes of enteric bacteria, β-lactamases producing bacteria, L. pneumophila (Legionella pneumophila) and H. pylori (Helicobacter pylori). Enteric bacteria were detected with high frequency in Palestinian water sources followed by 13% occurrence of β-lactamases producing bacteria, 9% of H. pylori and 4% of L. pneumophila. The study shows that shallow groundwater wells and water taped from karstic aquifer is potential for contamination and could not be reliable sources of potable water. 展开更多
关键词 Groundwater contamination Β-LACTAMASES 1-1. pylori waterborne pathogens.
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