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CoW合金钢轴向加载疲劳耐久性的研究
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作者 高倩倩 黄颐 +1 位作者 童第华 左强 《上海金属》 2025年第6期43-47,共5页
在室温和高温(550、600、630℃)对CoW合金钢进行不同应力比(R=-1、-0.5、0、0.4)的轴向加载疲劳试验,研究了温度和应力比对该钢疲劳耐久性的影响。结果表明:在同一应力水平下,试验钢的疲劳寿命随温度升高而下降;应力比为-1时试验钢的不... 在室温和高温(550、600、630℃)对CoW合金钢进行不同应力比(R=-1、-0.5、0、0.4)的轴向加载疲劳试验,研究了温度和应力比对该钢疲劳耐久性的影响。结果表明:在同一应力水平下,试验钢的疲劳寿命随温度升高而下降;应力比为-1时试验钢的不同温度疲劳寿命差距较大。在相同温度下,试验钢的疲劳寿命随应力比的增大而增加;室温疲劳寿命的差距较高温疲劳寿命的大。分别采用Gerber抛物线和三次多项式拟合试验钢的高温和室温疲劳试验数据,得到的疲劳极限Haigh图可确定钢的安全工作范围。 展开更多
关键词 cow合金钢 疲劳耐久 温度 应力比 Haigh图
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CoW基高效电催化剂的制备及尿素氧化性能研究
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作者 赵雨欣 祝彭宇 +5 位作者 朱斌 王新芳 邹佳润 闫婷婷 张笛笛 梁书芹 《安徽化工》 2025年第5期68-71,共4页
基于Co、W元素特性,精准调控原料配比、水热条件等参数,通过水热法制备CoW基催化剂,利用XRD、SEM、TEM及XPS等技术对催化剂结构与形貌进行表征,并在碱性环境下进行了析氧反应和尿素氧化性能的测试。结果表明:CoW基催化剂形成了雪花形状... 基于Co、W元素特性,精准调控原料配比、水热条件等参数,通过水热法制备CoW基催化剂,利用XRD、SEM、TEM及XPS等技术对催化剂结构与形貌进行表征,并在碱性环境下进行了析氧反应和尿素氧化性能的测试。结果表明:CoW基催化剂形成了雪花形状的微观结构,UOR性能卓越、起始电位低、半波电位优、塔菲尔斜率小、反应动力学快。该成果为UOR催化剂发展提供了新思路,后续可探索新制备法、开展多元复合与纳米结构设计,并推动其在能源转换与环境修复领域的工业化应用。 展开更多
关键词 尿素氧化反应 cow 电催化剂
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Robust Real-Time Analysis of Cow Behaviors Using Accelerometer Sensors and Decision Trees with Short Data Windows and Misalignment Compensation
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作者 Duc-Nghia Tran Viet-Manh Do +1 位作者 Manh-Tuyen Vi Duc-Tan Tran 《Computers, Materials & Continua》 2025年第5期2525-2553,共29页
This study focuses on the design and validation of a behavior classification system for cattle using behavioral data collected through accelerometer sensors.Data collection and behavioral analysis are achieved using m... This study focuses on the design and validation of a behavior classification system for cattle using behavioral data collected through accelerometer sensors.Data collection and behavioral analysis are achieved using machine learning(ML)algorithms through accelerometer sensors.However,behavioral analysis poses challenges due to the complexity of cow activities.The task becomes more challenging in a real-time behavioral analysis system with the requirement for shorter data windows and energy constraints.Shorter windows may lack sufficient information,reducing algorithm performance.Additionally,the sensor’s position on the cowsmay shift during practical use,altering the collected accelerometer data.This study addresses these challenges by employing a 3-s data window to analyze cow behaviors,specifically Feeding,Lying,Standing,and Walking.Data synchronization between accelerometer sensors placed on the neck and leg compensates for the lack of information in short data windows.Features such as the Vector of Dynamic Body Acceleration(VeDBA),Mean,Variance,and Kurtosis are utilized alongside the Decision Tree(DT)algorithm to address energy efficiency and ensure computational effectiveness.This study also evaluates the impact of sensor misalignment on behavior classification.Simulated datasets with varying levels of sensor misalignment were created,and the system’s classification accuracy exceeded 0.95 for the four behaviors across all datasets(including original and simulated misalignment datasets).Sensitivity(Sen)and PPV for all datasets were above 0.9.The study provides farmers and the dairy industry with a practical,energy-efficient system for continuously monitoring cattle behavior to enhance herd productivity while reducing labor costs. 展开更多
关键词 Monitoring behavior classification ACCELEROMETER sensor MISALIGNMENT leg-mounted neck-mounted cow
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Characterization of the colostrum proteome of primiparous Holstein cows and its association with colostrum immunoglobulin G concentrations
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作者 Ezequias Castillo-Lopez Patrick Biber +6 位作者 Arife Sener-Aydemir Karin Hummel Ebrahim Razzazi-Fazeli Nicole Reisinger Qendrim Zebeli Susanne Kreuzer-Redmer Thomas Hartinger 《Journal of Animal Science and Biotechnology》 2025年第2期931-947,共17页
Background The objective was to characterize the colostrum proteome of primiparous Holstein cows in association with immunoglobulin G(IgG)content.Immediately after calving,colostrum samples were collected from 18 cows... Background The objective was to characterize the colostrum proteome of primiparous Holstein cows in association with immunoglobulin G(IgG)content.Immediately after calving,colostrum samples were collected from 18 cows to measure IgG concentration.Based on colostrum IgG content,samples were classified through cluster analysis and were identified as poor,average,and excellent quality.The proteome was assessed with quantitative shotgun proteomics;abundance data were compared among the colostrum types;enrichment analysis of metabolic processes and proteins classes was performed as well.We also tested correlations between this proteome and blood globulin level of cows and passive immunity level of calves.Results On average,428 proteins were identified per sample,which belonged mainly to cellular process,biological regulation,response to stimulus,metabolic process,and immune system process.Most abundant proteins were complement C3(Q2UVX4),alpha-S1-casein(P02662),Ig-like domain-containing protein(A0A3Q1M032),albumin(A0A140T897),polymeric immunoglobulin receptor(P81265),lactotransferrrin(P24627),and IGHG1*01(X167014).Colostrum of excellent quality had greater(P<0.05)abundance of serpin A3-7(A2I7N3),complement factorl(A0A3Q1 MIF4),lipocalin/cytosolic fatty-acid binding domain-containing protein(A0A3Q1 MRQ2),complement C3(E1B805),complement component 4 binding protein alpha(A0AAF6ZHP5),and complement component C6(F1MM86).However,colostrum of excellent quality had lower(P<0.05)abundance of HGF activator(E1BCW0),alpha-S1-casein(P02662),and xanthine dehydrogenase/oxidase(P80457).This resulted in enrichment of the biological processes predominantly for complement activation alternative pathway,complement activation,complement activation classical pathway,humoral immune response,leukocyte mediated immunity,and negative regulation of endopeptidase activity in excellent-quality colostrum.Additionally,some colostrum proteins were found to be correlated with the blood globulin level of cows and with the passive immunity level of calves(P<0.05;r≥0.57).Conclusions This study provides new insights into the bovine colostrum proteome,demonstrating associations between IgG levels and the abundance of other proteins,as well as the enrichment of metabolic processes related to innate immune response.Thus,results suggest that the colostrum proteomic profile is associated with the content of IgG.Future research should deeply explore the association of these findings with pre-calving nutrition status and blood composition of the cow,and with passive immunity transfer to the calf. 展开更多
关键词 Bovine colostrum cow IMMUNOGLOBULINS Passive immunity PROTEOMICS
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Study on Proliferative Capacity,Milk Synthesis Characteristics and Cryopreservation Methods of Subcultured Dairy Cow Mammary Epithelial Cells
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作者 Li Lu Li Zhuolin +3 位作者 Wang Yuanhao Lv Wei Zhang Minghui Ao Jinxia 《Journal of Northeast Agricultural University(English Edition)》 2025年第4期74-82,共9页
A lactating dairy cow mammary epithelial cell(DCMEC)model is useful for studying milk synthesis and lactation in the dairy cow mammary gland.However,the cells can only maintain their original characteristics for a lim... A lactating dairy cow mammary epithelial cell(DCMEC)model is useful for studying milk synthesis and lactation in the dairy cow mammary gland.However,the cells can only maintain their original characteristics for a limited period in vitro.Thus,the proliferative capacity and lactation pattern of subcultured DCMECs need to be characterized.In the present study,subcultured DCMECs appeared to proliferate without changes in morphology or growth pattern up to the 12th passage.Subculturing had no obvious effect on the lactation capacity of the subcultured DCMEC up to the 10th passage in vitro.These results indicated that the DCMEC line could be subpassaged up to 10 times and still maintain its original milk synthesis characteristics.Moreover,DCMECs were frozen using different methods,and the method of placing the vials in the foam box was determined after cryopreservation with the best adherence of 91.2%.This method was recommended for long-term cryopreservation for DCMECs. 展开更多
关键词 dairy cow mammary epithelial cell SUBCULTURE PROLIFERATION LACTATION
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Effects of supplementing bile acids on the production performance,fatty acid and bile acid composition,and gut microbiota in transition dairy cows
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作者 Lei Li Jiaxiao Li +7 位作者 Zhihui Liu Zihan Jin Mengyang Wang Ying Wu Zhihong Zhang Xinfeng Hou Junhu Yao Jun Zhang 《Journal of Animal Science and Biotechnology》 2025年第5期2152-2169,共18页
Background During the transition period,cows are prone to negative energy balance,which can lead to a decline in production performance and health in severe cases.In recent years,it has been discovered that bile acids... Background During the transition period,cows are prone to negative energy balance,which can lead to a decline in production performance and health in severe cases.In recent years,it has been discovered that bile acids(BAs)can act not only as fat emulsifiers but also as signaling molecules to regulate body metabolism.Although BAs have been used to some extent in monogastric and aquatic animals,their role in ruminants,particularly in transition cows,remains unclear.Therefore,this study aimed to determine the effects of BAs on the production performance,milk and plasma fatty acid and BA composition,and fecal microbiota in transition dairy cows.Results Forty-six healthy transition Holstein dairy cows with similar conditions were randomly divided into two groups and supplemented with 0 or 20 g/d of BAs from 21 d before the expected calving to 21 d after calving.The production performance was tracked until 60 d after calving.The results indicated that BA supplementation significantly improved postpartum milk fat content and yields as well as the yields of unsaturated fatty acids,monounsaturated fatty acids,and polyunsaturated fatty acids in milk.There was a significant increase in the concentration of triglyceride and the proportion of C≤16 fatty acids in the plasma of cows supplemented with BAs,while the concentration of β-hydroxybutyrate and the proportion of C>16 fatty acids in the plasma decreased significantly.BA supplementation significantly altered the composition of the fecal bacterial community and increased the relative abundance of bacteria beneficial for BA metabolism and transformation(Romboutsia,Clostridium sensu_stricto_6,and Clostridium sensu_stricto_1).Functional prediction analysis showed that the relative abundance of bile salt hydrolase,7 α-hydroxysteroid dehydrogenase,and BA inducible E as well as the pathways related to BA metabolism also significantly increased in cows supplemented BAs.In addition,BA supplementation significantly altered the composition of plasma and fecal BAs,particularly increasing circulating secondary BA concentration,which might induce the complete oxidation of fatty acids in the liver and further reduce the concentration of β-hydroxybutyrate.Conclusions These findings highlight the potential benefits of BA supplementation in improving milk yields and quality,as well as influencing metabolic pathways in transition dairy cows.Meanwhile,further studies are needed to elucidate the underlying mechanisms and explore the broader implications of these results by using more tissue samples. 展开更多
关键词 Bile acids Fatty acids Gut microbiota Production performance Transition dairy cow
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Reducing crude protein content in the diet of lactating dairy cows improved nitrogen‑use‑efficiency and reduced N excretion in urine,whilst having no obvious effects on the rumen microbiome
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作者 Agalu W.Zeleke Nicholas J.Dimonaco +4 位作者 Katie Lawther Anna Lavery Conrad Ferris Jon Moorby Sharon A.Huws 《Journal of Animal Science and Biotechnology》 2025年第5期2458-2486,共29页
Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the envi... Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats,and to watercourses contributing to aquatic eutrophication.While there is much evidence that NUE can be improved by reducing the crude protein(CP)content of dairy cow diets,the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.This study examined the effects of reducing the CP contents of dairy cow diets on cow performance,NUE,the relationship between NUE and residual feed intake(RFI),and the rumen microbiome.Results Dietary CP content did not affect feed intake,milk yield or milk composition(P>0.05),except for milk urea N(MUN),which increased with increasing diet CP content(P<0.05).The mean NUE was 34%,34%and 31%for the LCP(low-protein,15%),MCP(medium-protein,16%),and HCP(high-protein,17%)diets,respectively.RFI was negatively correlated with NUE(r=−0.57,P<0.001).The rumen ammonia-N concentrations increased with increasing dietary CP;however,the ruminal pH and volatile fatty acid(VFA)content of the rumen fluid remained constant.Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.Reducing dietary CP content in dairy cow diets did not affect microbial composition,diversity and functional profiles.The family Bacteroidaceae was more abundant in HE(high-efficiency)cows,whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE(low-efficiency)cows.Additionally,propanoate metabolism,cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows,whilst the methane(CH4)metabolism pathway was upregulated in LE cows.Conclusions The results demonstrate that diet CP can be reduced with no loss in cow performance,but with an associated reduction in N excretion.The abundance of microbial populations differed between low and high efficiency cows,which may contribute to the differences in efficiency observed. 展开更多
关键词 Dairy cows Dietary crude protein Nitrogen excretion Nitrogen-use-efficiency Rumen microbiome
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Cow milk protein allergy mimics in infancy
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作者 Mohammed Al-Beltagi Nermin Kamal Saeed +2 位作者 Adel Salah Bediwy Hosameldin A Bediwy Reem Elbeltagi 《World Journal of Clinical Pediatrics》 2025年第3期17-39,共23页
Cow milk protein allergy(CMPA)is a prevalent food allergy in infancy.It often presents with symptoms that overlap with other conditions,such as gastroeso-phageal reflux disease,lactose intolerance,food protein-induced... Cow milk protein allergy(CMPA)is a prevalent food allergy in infancy.It often presents with symptoms that overlap with other conditions,such as gastroeso-phageal reflux disease,lactose intolerance,food protein-induced enterocolitis syndrome,and eosinophilic esophagitis.This diagnostic overlap makes distin-guishing CMPA from its mimics difficult,resulting in potential misdiagnoses and unnecessary dietary restrictions.This review aims to comprehensively analyze CMPA and its mimicking conditions,highlighting their clinical presentations,diagnostic approaches,and management strategies to enhance diagnostic accu-racy and optimize patient care.A systematic literature search was conducted using PubMed,Scopus,Web of Science,and Google Scholar,focusing on studies published within the last 20 years.Articles addressing CMPA and its mimicking conditions were selected,with data synthesized into comparative analyses of diagnostic methods and management strategies.Accurate differentiation between CMPA and its mimics requires a thorough clinical evaluation supported by diagnostic tests such as skin prick tests,serum-specific IgE,and oral food challenges.Misdiagnosis can lead to nutritional deficiencies,psychological stress,and increased healthcare costs.Emerging diagnostic technologies,including component-resolved diagnostics and cytokine profiling,offer promising avenues for improving accuracy.A multidisciplinary approach involving pediatricians,allergists,and dietitians is essential for precise diagnosis and effective management.Ongoing research and education are crucial to enhancing clinical outcomes and reducing the burden on families. 展开更多
关键词 cow milk protein allergy Diagnostic challenges Mimicking conditions Gastroesophageal reflux disease Lactose intolerance Food protein-induced enterocolitis syndrome Eosinophilic esophagitis
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基于优化的COW虚拟块设备的虚拟机按需部署机制 被引量:9
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作者 陈彬 肖侬 +1 位作者 蔡志平 王志英 《计算机学报》 EI CSCD 北大核心 2009年第10期1915-1926,共12页
基于COW(Copy-on-Write)读写模式的虚拟块设备有利于实现大规模虚拟机环境下虚拟机的快速部署.文中为虚拟机管理器中的COW虚拟块设备设计了一种优化方法,能够提高COW磁盘的访问性能以及生成多个小尺寸的COW磁盘映像文件,以降低通过网络... 基于COW(Copy-on-Write)读写模式的虚拟块设备有利于实现大规模虚拟机环境下虚拟机的快速部署.文中为虚拟机管理器中的COW虚拟块设备设计了一种优化方法,能够提高COW磁盘的访问性能以及生成多个小尺寸的COW磁盘映像文件,以降低通过网络部署虚拟机的开销.基于优化的COW虚拟块设备,文中提出了虚拟机环境下的虚拟机按需部署机制及关键技术问题的解决方案.基于Linux平台和QEMU虚拟机,实现了基于优化COW虚拟块设备的虚拟机按需部署原型系统.实验表明,优化的COW虚拟块设备、基于COW磁盘有效工作集的优化部署以及COW磁盘回收等方法能够有效地支持虚拟机环境下低开销的、按需的虚拟机部署. 展开更多
关键词 虚拟机 虚拟机管理器 虚拟机按需部署 cow磁盘 有效工作集
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Study on the Effects of Chinese Herb Additive on Milk Yield and Anti-heat Stress Ability of Holstein Cow 被引量:21
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作者 赵政 陈学文 李仕坚 《Agricultural Science & Technology》 CAS 2008年第3期111-114,共4页
[Objective] The research aimed to explore the effects of Chinese herb additive on milk yield and anti-heat stress ability of Holstein cow.[Method] 36 Holstein cows with similar birth order and milk yield were equally ... [Objective] The research aimed to explore the effects of Chinese herb additive on milk yield and anti-heat stress ability of Holstein cow.[Method] 36 Holstein cows with similar birth order and milk yield were equally and randomly divided into 3 groups which were control group, Chinese medicine Ⅰ group and Chinese medicine Ⅱ group. In control group, cows were fed with basic feed, while in Chinese medicine Ⅰ group, cows were fed with basic feed containing 4% compound Chinese herb additive and in Chinese medicine Ⅱ group, cows were fed with basic feed containing 3% compound Chinese herb additive.All cows in the 3 groups were analyzed comparatively.[Result] Adding some compound Chinese herb additive into basic feed would increase milk yield and anti-heat stress ability of Holstein cow,besides,it also could decrease cow diseases such as cow mastitis.Chinese medicine Ⅰ would generate the highest economic benefit of practical production.[Conclusion] Adding Chinese herb additive into basic feed is an effective way for reliefing heat stress and increasing milk yield. 展开更多
关键词 Chinese HERB ADDITIVE HOLSTEIN cow Milk yield Anti-heat stress
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油罐机械清洗设备COW在我国的首次应用 被引量:10
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作者 蒋连生 戴良 +2 位作者 徐峰 贺立平 马成山 《油气储运》 CAS 北大核心 1998年第2期37-41,共5页
对引进日本的机械清洗设备COW,在东营首站第一次使用的情况做了较详细的介绍。该项技术在油罐的清洗中具有机械化程度高、施工周期短、安全可靠、原油回收率高、不会对环境造成污染、综合效益高等优点。同时介绍了COW设备的组成及清洗... 对引进日本的机械清洗设备COW,在东营首站第一次使用的情况做了较详细的介绍。该项技术在油罐的清洗中具有机械化程度高、施工周期短、安全可靠、原油回收率高、不会对环境造成污染、综合效益高等优点。同时介绍了COW设备的组成及清洗施工现场的布置情况,并指出了在今后清洗作业中应注意的事项。 展开更多
关键词 油罐 cow 机械清洗设备 维修
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Effects of Enzyme on Material Transformation of Cow Dung Compost 被引量:7
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作者 任平 徐升运 +1 位作者 阮祥稳 赵文娟 《Agricultural Science & Technology》 CAS 2010年第3期143-146,共4页
[Objective] The aim was to study change of the composition of cow dung compost by adding complex enzyme.[Method] 2.0% enzyme treatment group,1.5% enzyme treatment group and control group were set to analyze temperatur... [Objective] The aim was to study change of the composition of cow dung compost by adding complex enzyme.[Method] 2.0% enzyme treatment group,1.5% enzyme treatment group and control group were set to analyze temperature,moisture,pH value,crude fiber,TOC,TN,GI during composting.[Result] The results showed that adding complex enzymes could accelerate degradation of organic matter in pre-composting period.Crude fiber of 2.0%,.1.5% enzyme treatment group and control group decreased 49.6%,47% and 29.1% respectively,TOC decreased 41.7%,35.3% and 21.1%,TN decreased 32.6%,26.8% and 19.2%.2.0%,1.5% enzyme treatment groups could reach basic maturity degree at 30 d.[Conclusion] Composting cycle be shortened by adding complex enzymes,which was useful for maturity of cow dung compost. 展开更多
关键词 ENZYME cow dung COMPOST
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Effects of Herbal Feed Additive on Milk Production of Dairy Cows 被引量:5
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作者 高桂生 高光平 +4 位作者 李正本 史秋梅 张艳英 邵新华 梁银聚 《Agricultural Science & Technology》 CAS 2013年第10期1462-1464,共3页
[Objective] The aim of this study was to investigate the efficacy of the herbal feed additive Zengrujianniusan on the milk production of dairy cows. [Method] Thirty-two black-white lactating cows were randomly divided... [Objective] The aim of this study was to investigate the efficacy of the herbal feed additive Zengrujianniusan on the milk production of dairy cows. [Method] Thirty-two black-white lactating cows were randomly divided into four groups, and were fed with forage supplemented with 0 (control group), 0.2%, 0.4% and 0.6% Zengrujianniusan for 60 d. During this period, the contents of fat, protein and non-fat solid in milk were measured every 20 d. [Result] The milk production of the cows whose forage was added with 0.2 %, 0.4 % and 0.6% Zengrujianniusan was 4.02%, 12.50%, 14.00% higher than that of the control (P〉0.05). The herbal feed additive had no significant influence on the contents of fat, milk and non-fat solid in milk, but significantly reduced the number of somatic cells. [Conclusion] The study will provide reference for developing feed additives which is safe and non-toxic to cows and their milk. 展开更多
关键词 Herbal feed additive Lactating cows Milk production
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CoW_(11)Ti/淀粉纳米复合物的合成与表征 被引量:2
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作者 王晓红 王立敏 +1 位作者 李凤 刘景福 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2003年第12期2158-2160,共3页
Using a reversed-phase microemulsion polymerization method, polyoxometalates(POMs) CoW 11Ti loaded starch nanoparticles were prepared and structurally characterized by elemental analyses, IR, UV-Vis and ESR spectrosco... Using a reversed-phase microemulsion polymerization method, polyoxometalates(POMs) CoW 11Ti loaded starch nanoparticles were prepared and structurally characterized by elemental analyses, IR, UV-Vis and ESR spectroscopy. The particle size of CoW 11Ti/starch was estimated by transmission electron microscope(TEM) and the size ranges by a 1000HSA MALVIRN Zetasizer instrument. The result shows that the polyoxometalate retained the parent structure after encapsulated by starch microspheres, which are able to enhance the stability and antitumoral activity of POMs and decrease the toxicity of POMs as well. 展开更多
关键词 多酸化合物 K6H2[cow11TiO40]·12H2O 淀粉纳米粒子 载药体系 合成 表征 抗HIV病毒活性 抗肿瘤活性
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K_5CoW_(12)O_(40)·3H_2O催化合成苯甲醛1,2-丙二醇缩醛 被引量:5
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作者 赖君玲 刘春生 +1 位作者 罗根祥 沈飞 《辽宁石油化工大学学报》 CAS 2010年第2期1-3,共3页
研究了K5CoW12O40.3H2O催化剂对苯甲醛和1,2-丙二醇为原料合成苯甲醛1,2-丙二醇缩醛的反应的催化活性。考察了醛醇物质的量比、催化剂质量、带水剂体积、反应时间、催化剂重复使用性等因素对产品收率的影响。结果表明,K5CoW12O40.3H2O... 研究了K5CoW12O40.3H2O催化剂对苯甲醛和1,2-丙二醇为原料合成苯甲醛1,2-丙二醇缩醛的反应的催化活性。考察了醛醇物质的量比、催化剂质量、带水剂体积、反应时间、催化剂重复使用性等因素对产品收率的影响。结果表明,K5CoW12O40.3H2O是缩醛反应的良好催化剂。在最佳实验条件下:苯甲醛与1,2-丙二醇物质的量比为1:1.2、苯甲醛物质的量为0.1mol、催化剂质量为0.3g、环己烷体积为10mL、反应时间45min,苯甲醛1,2-丙二醇缩醛的收率最高可达92.8%。 展开更多
关键词 苯甲醛l 2-丙二醇缩醛 K5cow12O40·3H2O 催化 缩醛反应
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并行多种群自适应遗传算法在COW集群上的实现 被引量:1
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作者 刘虎 张焕春 +1 位作者 经亚枝 朱力立 《南京航空航天大学学报》 EI CAS CSCD 北大核心 2005年第6期760-765,共6页
为改善标准遗传算法的求解效率,提出一种基于6模糊控制器的并行多种群自适应遗传算法。利用MPI(Messagepassinginterface)技术建立了一个COW(Clusterofworkstation)集群,将算法在该硬件平台上进行了实现。3机COW集群的仿真实验结果在演... 为改善标准遗传算法的求解效率,提出一种基于6模糊控制器的并行多种群自适应遗传算法。利用MPI(Messagepassinginterface)技术建立了一个COW(Clusterofworkstation)集群,将算法在该硬件平台上进行了实现。3机COW集群的仿真实验结果在演示算法设计可行性的同时,表明该算法的求解效率明显优于用于对照的单种群算法,具有在解决组合优化问题上广泛应用的可能。本文还对影响并行算法的参数进行了探讨。 展开更多
关键词 并行遗传算法 自适应参数控制 cow集群 MPI
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Effects of Oral Administration of Propylene Glycol and Ca-P-Mg Mixture on Milk Quality and SCC of Dairy Cows after Birth 被引量:1
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作者 段素云 侯引绪 +1 位作者 施振声 孙健 《Agricultural Science & Technology》 CAS 2016年第1期141-143,共3页
In order to further study the postpartum care technology of dairy cows,the effects of oral administration of propylene glycol or Ca-P-Mg mixture and compound oral rehydration salts on milk quality and SCC of dairy cow... In order to further study the postpartum care technology of dairy cows,the effects of oral administration of propylene glycol or Ca-P-Mg mixture and compound oral rehydration salts on milk quality and SCC of dairy cows after birth were investigated. The results showed that the milk fat and dry matter contents in the dairy cows administered with Ca-P-Mg mixture and compound oral rehydration salts were higher than those in the dairy cows administered with propylene glycol(P 〈0.05). However, there were no significant differences in milk sugar and protein contents and SCC between the two administration groups. 展开更多
关键词 Dairy cow Postnatal administration Propylene glycol Ca-P-Mg mixture Contrast test
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CeO_2-TiO_2/[CoW_(12)O_(40)]^(5-)-HTLC的制备及光催化性能 被引量:1
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作者 薛茹君 周敏 +1 位作者 陈淑芬 陈春阳 《安徽理工大学学报(自然科学版)》 CAS 2013年第1期5-9,共5页
为了克服杂多酸易溶于极性溶剂,较难回收重复使用的缺点,采用共沉淀法制备了镁铝水滑石;并以硝酸根型水滑石作为前体,通过插层组装合成了杂多阴离子[CoW12O40]5--HTLC;再采用微乳液法将CeO2掺杂的TiO2负载到[CoW12O40]5--HTLC上,焙烧后... 为了克服杂多酸易溶于极性溶剂,较难回收重复使用的缺点,采用共沉淀法制备了镁铝水滑石;并以硝酸根型水滑石作为前体,通过插层组装合成了杂多阴离子[CoW12O40]5--HTLC;再采用微乳液法将CeO2掺杂的TiO2负载到[CoW12O40]5--HTLC上,焙烧后得到CeO2-TiO2/[CoW12O40]5--HTLC光催化剂。采用XRD、FT-IR、SEM-EDS和UV-Vis漫反射光谱等手段对催化剂进行了表征;以甲基橙为模拟污染物,考察了催化剂样品的光催化性能。实验结果表明:CeO2掺杂TiO2复合粒子在可见光区吸光性能高于TiO2;CeO2掺杂TiO2与杂多阴离子[CoW12O40]5-有协同光催化作用,CeO2-TiO2/[CoW12O40]5--HTLC光催化剂对可见光的吸收大大增强。经模拟日光照射2 h,15%(CeO2-TiO2)/5%[CoW12O40]5--HTLC催化剂对甲基橙的脱色率达到93%。 展开更多
关键词 CeO2-TiO2/[cow12O40]5--HTLC 光催化剂 制备 性能
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Optimizing Yanbian Cow Oocytes Mature in vitro and Cleavage System after Nuclear Transfer Based on Uniform Design 被引量:6
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作者 苗婷婷 魏世宝 《Agricultural Science & Technology》 CAS 2009年第5期113-115,共3页
[Objective] The aim was to optimize Yanbian cow oocytes mature in vitro and cleavage system after nuclear transfer based on uniform design. [Method] Oocytes were recovered by aspiration method, and oocytes were mature... [Objective] The aim was to optimize Yanbian cow oocytes mature in vitro and cleavage system after nuclear transfer based on uniform design. [Method] Oocytes were recovered by aspiration method, and oocytes were matured in vitro (IVM) with different conditions, and then carried out nucleus transfer, fusion, activation and in vitro culture (IVC) of embryo. Effects of ovary storage temperature, maturation time and follicular diameter size on in vitro maturation and cleavage rates of cow oocytes were compared. [ Result] The best conditions of IVM of Yanbian cow oocytes was that: the oocytes of 8 mm diameter were matured in vitro for 24 hours when the ovaries were stored at 26℃ or 31 ℃. The best cleave conditions after nucleus transfer of oocytes was that: the oocytes of 6 mm or 8 mm diameter were cultured in vitro for 24 hours when the ovaries were stored at 26℃. [ Conclusion] The result has some reference to Yanbian cow and other cow breeding and population expanding propagation. 展开更多
关键词 Uniform design Yanbian cow OOCYTES MATURE CLEAVAGE
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Protective Effect of Distillate and Redistillate of Cow’s Urine in Human Polymorphonuclear Leukocytes Challenged With Established Genotoxic Chemicals 被引量:3
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作者 K.KRISHNAMURTHI DIPANWITA DUTTA +1 位作者 S.D.SIVANESAN T. CHAKRABARTI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第3期247-256,共10页
Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to ca... Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to cause weight loss, reversal of certain cardiac and kidney problems, indigestion, stomach ache, edema, etc. However, the literature and scripture did not mention the antigenotoxic properties of cow’urine. Methods In the present investigation, the antigenotoxic/ antioxidant properties of cow’ urine distillate and redistillate were studied in vitro. The antioxidant status and volatile fatty acid levels were determined. Actinomycin-D (0.1ol/L) and hydrogen peroxide (150 mol/L) were used for inducing DNA strand break with 0.1% DMSO as negative control. Dose for the antigenotoxic effect of cow’ urine was chosen from the dose response study carried out earlier. Results Both actinomycin-D and H2O2 caused statistically significant DNA unwinding of 80% & 75% respectively (P<0.001) as revealed by fluorimetric analysis of DNA unwinding (FADU), and the damage could be protected with the redistilled cow urine distillate (1, 50 & 100 ) in simultaneous treatment with genotoxic chemicals. Conclusion The redistillate of cowurine was found to possess total antioxidant status of around 2.6 mmol, contributed mainly by volatile fatty acids (1500 mg/L) as revealed by the GC-MS studies. These fatty acids and other antioxidants might cause the observed protective effects. 展开更多
关键词 Ammonia Antioxidants cow urine distillate cow urine redistillate Human polymorphonuclear leukocytes(PMNL) DNA damage Fluorimetric analysis of DNA unwinding(FADU) Gas chromatography mass spectrometer(GC-MS) GENOTOXICITY Volatile fatt
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