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商合杭高铁裕溪河特大桥铺设无砟轨道关键技术研究 被引量:39
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作者 李秋义 张晓江 韦合导 《中国铁路》 2020年第6期44-51,共8页
大跨度桥梁铺设无砟轨道是世界性难题。商合杭高铁裕溪河特大桥主跨324 m,运用系统工程的思想,把桥梁和轨道作为一个有机整体,开展一体化设计,确定了预拱度设置方式、桥梁合理竖向刚度、轨道隔离层设置及接口要求;建立"车辆-轨道-... 大跨度桥梁铺设无砟轨道是世界性难题。商合杭高铁裕溪河特大桥主跨324 m,运用系统工程的思想,把桥梁和轨道作为一个有机整体,开展一体化设计,确定了预拱度设置方式、桥梁合理竖向刚度、轨道隔离层设置及接口要求;建立"车辆-轨道-桥梁"系统动力学模型,进行动力性能分析;提出施工线形控制、精密测量控制、静态验收标准等关键技术指标。结果表明,裕溪河特大桥主跨324 m铺设无砟轨道可行,满足高速列车通过的安全性、平顺性和舒适性要求,对于提升我国大跨度桥梁无砟轨道设计、施工及养护维修的技术水平具有重要意义。 展开更多
关键词 商合杭高铁 裕溪河特大桥 大跨度 铺设 无砟轨道
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An Overview of Deepwater Pipeline Laying Technology 被引量:19
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作者 李志刚 王琮 +1 位作者 何宁 赵冬岩 《China Ocean Engineering》 SCIE EI 2008年第3期521-532,共12页
The technology and methods involved in pipeline laying in shallow water have evolved to the level of routine and commonplace. However, regarding the unexpected deepwater complexity, the traditional pipeline laying tec... The technology and methods involved in pipeline laying in shallow water have evolved to the level of routine and commonplace. However, regarding the unexpected deepwater complexity, the traditional pipeline laying techniques have to confront many new challenges arisen from the increase of the water depth, diameter of the pipe and the welding difficuhy, all of which should be modified and/or innovated based on the existed mature experiences. The purpose of this investigation is to outline the existing and new engineering laying techniques and the associated facilities, which can provide some significant information to the related research. In the context, the latest deepwater pipeline laying technology and pipe laying barges of the renowned companies from Switzerland, Norway, Italy etc., are introduced and the corresponding comparison and discussion are presented as well. 展开更多
关键词 DEEPWATER PIPELINE pipeline installation method pipe laying barge/vessel
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城市轨道交通轨道扣件综述 被引量:19
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作者 于春华 《铁道工程学报》 EI 2003年第3期31-33,22,共4页
阐述城市轨道交通轨道扣件的作用及设计原则 ,介绍我国铺设的扣件类型及性能 ,并提出了点滴建议。
关键词 城市轨道交通 轨道扣件 设计原则 类型 性能 铺设
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Dietary oregano essential oil supplementation improves intestinal functions and alters gut microbiota in latephase laying hens 被引量:15
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作者 Jia Feng Mingyuan Lu +4 位作者 Jing Wang Haijun Zhang Kai Qiu Guanghai Qi Shugeng Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第1期265-279,共15页
Background:Dietary essential oil(EO)supplementation can exert favorable effects on gut health in broilers.However,it is unknown whether EO could improve intestinal functions,consequently beneficial for egg performance... Background:Dietary essential oil(EO)supplementation can exert favorable effects on gut health in broilers.However,it is unknown whether EO could improve intestinal functions,consequently beneficial for egg performance and quality in late-phase laying hens.This study was aimed to investigate the potential effects of EO on production performance,egg quality,intestinal health and ileal microbiota of hens in the late phase of production.A total of 28860-week-old Hy-line Brown laying hens were randomly divided into 4 groups and fed a basal diet(control)or basal diets supplemented with oregano EO at 100,200 and 400 mg/kg(EO100,EO200 and EO400).Results:Dietary EO supplementation resulted in a quadratic decrease(P<0.05)in feed conversion ratio with lower(P<0.05)feed conversion ratio in EO200 group than the control during weeks 9–12 and 1–12 of the trial.Compared to the control,EO addition resulted in higher(P<0.05)eggshell thickness at the end of week.4,8 and 12 and higher(P<0.05)chymotrypsin activity.There was a quadratic elevation(P<0.05)in ileal chymotrypsin and lipase activity,along with a linear increase in villus height to crypt depth ratio.Quadratic declines(P<0.05)in mRNA expression of IL-1β,TNF-α,IFN-γ and TLR-4,concurrent with a linear and quadratic increase(P<0.05)in ZO-1 expression were identified in the ileum with EO addition.These favorable effects were maximized at medium dosage(200 mg/kg)of EO addition and intestinal microbial composition in the control and EO200 groups were assessed.Dietary EO addition increased(P<0.05)the abundances of Burkholderiales,Actinobacteria,Bifidobacteriales,Enterococcaceae and Bacillaceae,whereas decreased Shigella abundance in the ileum.Conclusions:Dietary EO addition could enhance digestive enzyme activity,improve gut morphology,epithelial barrier functions and modulate mucosal immune status by altering microbial composition,thus favoring feed efficiency and eggshell quality of late-phase laying hens. 展开更多
关键词 Essential oil Feed efficiency Immune status Late-phase laying hen MICROBIOTA
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Effects of metabolizable energy and crude protein levels on laying performance,egg quality and serum biochemical indices of Fengda-1 layers 被引量:13
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作者 Yang Ding Xingchen Bu +2 位作者 Nannan Zhang Lanlan Li Xiaoting Zou 《Animal Nutrition》 SCIE 2016年第2期93-98,共6页
This study was conducted to investigate the effects of dietary ME and CP levels on laying performance, egg quality and serum biochemical indices of Fengda-1 layers. In a 2 × 3 factorial arrangement, 2,400 Fengda-... This study was conducted to investigate the effects of dietary ME and CP levels on laying performance, egg quality and serum biochemical indices of Fengda-1 layers. In a 2 × 3 factorial arrangement, 2,400 Fengda-1 layers(32 wk of age) were randomly assigned to 6 experimental diets with 2,650 and 2,750 kcal of ME/kg of diet, each containing 14.50%, 15.00% and 15.50% CP, respectively. Each dietary treatment was replicated 5 times, and feed and water were provided ad libitum. The trial lasted for 10 wk, including a2-week acclimation period and an 8-week experimental period. Our results showed that ADFI decreased as the ME level of diet increased from 2,650 to 2,750 kcal/kg(P< 0.05). Layers fed diets with 2,750 kcal/kg ME exhibited higher mortality than those fed with 2,650 kcal/kg ME(P < 0.05). Birds fed with 14.50% and15.00% CP had higher egg production(EP) and egg mass(EM) than those fed with 15.50% CP(P < 0.05).Yolk color increased as the ME level of the diet increased from 2,650 to 2,750 kcal/kg, however, the eggshell thickness decreased(P < 0.05). Serum concentrations of uric acid and triglyceride in layers fed diets with 2,750 kcal/kg ME were higher than those fed diets with 2,650 kcal/kg ME(P < 0.05). There was no significant interaction between ME and CP on laying performance, egg quality, or serum biochemical indices(P > 0.05). Based on the data under the experimental conditions, the optimal dietary ME and CP levels of Fengda-1 layers are 2,650 kcal/kg and 15.00%(33 to 41 wk of age). 展开更多
关键词 ENERGY PROTEIN laying performance Egg quality Fengda-1 layers
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Effects of essential oils on performance,egg quality, nutrient digestibility and yolk fatty acid profile in laying hens 被引量:12
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作者 Xuemei Ding Yang Yu +1 位作者 Zhuowei Su Keying Zhang 《Animal Nutrition》 SCIE 2017年第2期127-131,共5页
The study was conducted to investigate the effect of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens. A total of 960 Lohmann laying hens aged 53 weeks were... The study was conducted to investigate the effect of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens. A total of 960 Lohmann laying hens aged 53 weeks were enrolled, under 4 different treatment diets supplemented with 0, 50.100 and 150 mg/kg essential oils(Enviva EO, Dupont Nutrition Biosciences ApS, Denmark), respectively. Each treatment was replicated8 times with 30 birds each. Birds were fed dietary treatment diets for 12 weeks(54 to 65 weeks). For data recording and analysis, a 12-week period was divided into 3 periods of 4 weeks' duration each: period 1(54 to 57 weeks), period 2(58 to 61 weeks), and period 3(62 to 65 weeks). For the diet supplemented with Enviva EO, hen-day egg production and the feed conversion ratio(FCR) were significantly improved(P < 0.05) at weeks 58 to 61, and the eggshell thickness was significantly increased(P < 0.05) at week 65.However, egg production, egg weight, feed intake, FCR and other egg quality parameters(albumen height, Haugh unit, egg yolk color and eggshell strength) were not affected by the dietary treatment. In addition, compared with the control diet, protein digestibility in the 100 mg/kg Enviva EO treatment group was significantly increased(P < 0.05), and fat digestibility in the 100 and 150 mg/kg Enviva EO treatment groups was significantly decreased(P < 0.05), but Enviva EO had no effect on energy apparent digestibility. Saturated fatty acid(SFA) and monounsaturated fatty acid(MUFA) gradually decreased and polyunsaturated fatty acid(PUFA) increased with Enviva EO supplementation, but the difference was not significant. The data suggested that the supplementation of essential oils(Enviva EO) in laying hen diet did not show a significant positive effect on performance and yolk fatty acid composition but it tended to increase eggshell thickness and protein digestibility, especially at the dose of 50 mg/kg. 展开更多
关键词 Essential oils PERFORMANCE Egg quality Nutrient digestibility Yolk fatty acid profile laying hens
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航行敷设时海底电缆的受力分析 被引量:13
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作者 陈然 梅文杰 +2 位作者 狄健 姜山 谈志武 《光纤与电缆及其应用技术》 2018年第6期29-31,33,共4页
海底电缆(海缆)的敷设已成为电缆行业最具技术代表性的课题之一。基于海缆的敷设方法及其特点,提出了通过控制海缆张力的方法达到控制海缆航行敷设作业的思路。对海缆铠装可承受拉力、海缆盘绕时退扭力和张力的关系、海缆航行敷设时弯... 海底电缆(海缆)的敷设已成为电缆行业最具技术代表性的课题之一。基于海缆的敷设方法及其特点,提出了通过控制海缆张力的方法达到控制海缆航行敷设作业的思路。对海缆铠装可承受拉力、海缆盘绕时退扭力和张力的关系、海缆航行敷设时弯曲半径和张力的关系进行了计算分析。据此对海缆的敷设以及结构设计提出了一些合理的改进建议。 展开更多
关键词 海底电缆 敷设 张力
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超高层建筑无支撑钢筋桁架楼承板施工技术 被引量:12
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作者 李勇 《施工技术》 CAS 2018年第14期147-150,共4页
以首旅大厦为工程背景,论述钢筋桁架楼承板施工技术在高层劲性混凝土框架-核心筒结构中的应用。分析钢筋桁架楼承板运输、存放、吊装、支撑角钢精准焊接固定、楼板洞口预留等施工工艺的重难点,提出相应的解决措施。重点阐述钢筋桁架楼... 以首旅大厦为工程背景,论述钢筋桁架楼承板施工技术在高层劲性混凝土框架-核心筒结构中的应用。分析钢筋桁架楼承板运输、存放、吊装、支撑角钢精准焊接固定、楼板洞口预留等施工工艺的重难点,提出相应的解决措施。重点阐述钢筋桁架楼承板主要施工流程及安全与质量控制要点。 展开更多
关键词 高层建筑 钢筋桁架楼承板 吊装 铺设 焊接 施工技术
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公路路面施工中沥青摊铺的施工技术分析 被引量:12
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作者 叶祺 黄炜 《交通节能与环保》 2016年第6期74-76,共3页
本文结合作者多年的施工经验,分别从沥青摊铺的技术特征、摊铺前的技术准备工作、摊铺施工过程中的技术运用以及摊铺完成后的测查等阶段,综合分析了沥青摊铺技术在公路路面施工中的运用,以期为同类工程提供借鉴。
关键词 路面 沥青 铺设 技术
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Laying hen performance,egg quality improved and yolk 5-methyltetrahydrofolate content increased by dietary supplementation of folic acid 被引量:10
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作者 Sattar Bagheri Hossein Janmohammadi +2 位作者 Ramin Maleki Alireza Ostadrahimi Ruhollah Kianfar 《Animal Nutrition》 SCIE 2019年第2期130-133,共4页
This study was performed to evaluate the effect of folic acid(FA) on performance, egg quality and yolk5-methyltetrahydrofolate(5-MTHF) content. A total of 384 Hy-line W36 strain hens from 52 to 58 weeks of age were ra... This study was performed to evaluate the effect of folic acid(FA) on performance, egg quality and yolk5-methyltetrahydrofolate(5-MTHF) content. A total of 384 Hy-line W36 strain hens from 52 to 58 weeks of age were randomly assigned to 4 groups, and each group received one of following dietary treatments:0, 5.10 and 15 mg FA/kg diet. A completely randomized design was used. Egg production percentage, egg mass and egg weight were increased significantly(P < 0.05) and feed conversion ratio(FCR) was reduced significantly(P < 0.05) by increasing FA content in diets. No significant differences were detected among treatments on egg quality except for shell thickness. The dietary supplementations of laying hens diets with FA significantly increased yolk 5-MTHF content(P = 0.02). Overall, these data demonstrate that dietary supplementation with FA raised 5-MTHF content of yolk and productivity of egg production in laying hens. 展开更多
关键词 Folic ACID 5-Methyltetrahydrofolate laying HENS YOLK EGG
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Effects of dietary glycerol monolaurate on productive performance, egg quality, serum biochemical indices, and intestinal morphology of laying hens 被引量:11
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作者 Min-jie ZHAO Hai-ying CAI +4 位作者 Meng-yun LIU Ling-li DENG Yang LI Hui ZHANG Feng-qin FENG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2019年第11期877-890,共14页
Glycerol mono laurate(GML)has been widely used as an effective antibacterial emulsifier in the food in?dustry.A total of 360 44-week-old Hy-Line brown laying hens were randomly distributed into four groups each with s... Glycerol mono laurate(GML)has been widely used as an effective antibacterial emulsifier in the food in?dustry.A total of 360 44-week-old Hy-Line brown laying hens were randomly distributed into four groups each with six replicates of 15 birds,and fed with com-soybean-meal-based diets supplemented with 0,0.15,0.30,and 0.45 g/kg GML,respectively.Our results showed that 0.15,0.30,and 0.45 g/kg GML treatments significantly decreased feed conversion ratios(FCRs)by 2.65%,7.08%,and 3.54%,respectively,and significantly increased the laying rates and average egg weights.For egg quality,GML drastically in creased albume n height and Haugh units,and enhanced yolk color.Notably,GML increased the concentrations of polyunsaturated and monounsaturated fatty acids and reduced the concentration of total saturated fatty acids in the yolk.The albumen composition was also significantly modified,with an increase of 1.02%in total protein content,and increased 8ntents of His(4.55%)and Glu(2.02%)under the 0.30 g/kg GML treatment.Additionally,GML treatments had positive effects on the lipid metabolism of laying hens,including lowering the serum triglyceride and total cholesterol levels and reducing fat deposit!on in abdominal adipose tissue.Intestinal morphology was also improved by GML treatment,with increased villus length and villus height to crypt depth ratio.Our data demonstrated that GML supplementation of laying hens could have beneficial effects on both their productivity and physiological properties,which indicates the potential application of GML as a functional feed additive and gives us a new in sight into this traditional food additive. 展开更多
关键词 Glycerol monolaurate (GML) laying hen Productive performance Egg quality Lipid metabolism
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膨润土防水毯施工技术的研究与应用 被引量:11
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作者 曲春珑 周卉鑫 《建筑技术》 北大核心 2011年第7期590-593,共4页
膨润土防水毯的国家或行业标准尚未正式颁布。在施工中针对具体情况,采用了相应的施工方法,解决了膨润土防水毯的大面积铺设、防水毯与其他防水材料的搭接、防水毯破损处的修补、施工缝及变形缝处细部构造等施工难题,收到了预期效果,形... 膨润土防水毯的国家或行业标准尚未正式颁布。在施工中针对具体情况,采用了相应的施工方法,解决了膨润土防水毯的大面积铺设、防水毯与其他防水材料的搭接、防水毯破损处的修补、施工缝及变形缝处细部构造等施工难题,收到了预期效果,形成了一套完整的专项技术。 展开更多
关键词 膨润土 防水毯 性能 铺设 细部构造
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Dietary supplemental xylooligosaccharide modulates nutrient digestibility,intestinal morphology,and gut microbiota in laying hens 被引量:10
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作者 Jianmin Zhou Shugeng Wu +4 位作者 Guanghai Qi Yu Fu Weiwei Wang Haijun Zhang Jing Wang 《Animal Nutrition》 SCIE CSCD 2021年第1期152-162,共11页
This study was conducted to evaluate the prebiotic effects of dietary xylooligosaccharide(XOS)sup-plementation on performance,nutrient digestibility,intestinal morphology,and gut microbiota in laying hens.In a 12-wk e... This study was conducted to evaluate the prebiotic effects of dietary xylooligosaccharide(XOS)sup-plementation on performance,nutrient digestibility,intestinal morphology,and gut microbiota in laying hens.In a 12-wk experiment,a total of 288 Hy-Line Brown layers at 50 wk of age were randomly assigned into 3 dietary treatments supplemented with XOS at 0,200 or 400 mg/kg.Each treatment had 8 replicates with 12 birds each.Hens fed XOS diets showed a lower feed-to-egg ratio during wk 7 to 12 and a higher egg yolk color value in wk 12 compared with those fed the control diet(P<0.05).Dietary XOS supplementation improved the apparent total tract digestibility of gross energy and nitrogen at the end of the 12th wk(P<0.05).In addition,a higher villus height-to-crypt depth ratio of the ileum was observed in XOS-added groups(P<0.05).The high throughput sequencing analysis of bacterial 16S rRNA revealed that dietary XOS supplementation at 200 mg/kg altered cecal microbiota.Alpha diversity analysis illustrated a higher cecal bacterial richness in birds fed with XOS at 200 mg/kg.The composition of cecal microbiota modulated by the XOS addition was characterized by an increased abundance of Firmicutes along with a reduced abundance of Bacteroidetes.At the genus level,dietary XOS supple-mentation triggered decreases in Bacteroides and Campylobacter concurrent with increases in Lactoba-cillus and several short chain fatty acid producers including Desulfovibrio,Faecalitalea,Faecalicoccus,and 5 genera of family Lachnospiraceae.Collectively,dietary XOS addition improved the feed conversion ratio by modulating nutrient digestibility and ileal morphology in laying hens,which could be attributed to the enhancement of bacterial diversity and alteration of microbial composition. 展开更多
关键词 Gut microbiota Ileal morphology laying hen Nutrient digestibility XYLOOLIGOSACCHARIDE
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利用自埋技术铺设海底管道 被引量:6
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作者 孙洪生 《石油工程建设》 2005年第1期12-13,共2页
在海底管道施工过程中,一般采用预挖沟或后挖沟方法埋设海底管道,但是这两种方法都需要价格昂贵的施工设备。文章介绍了一种新技术,不用挖沟就可以进行海底管道的埋设。在管道的上方安装类似鱼“鳍”的阻流板,当海底管道的路由垂直于海... 在海底管道施工过程中,一般采用预挖沟或后挖沟方法埋设海底管道,但是这两种方法都需要价格昂贵的施工设备。文章介绍了一种新技术,不用挖沟就可以进行海底管道的埋设。在管道的上方安装类似鱼“鳍”的阻流板,当海底管道的路由垂直于海水的流动方向时,利用水流的作用在管道的底部冲刷出一定深度的管沟,从而将管道埋在1~1.5倍管径的深度。文章还介绍了阻流板的结构形式、安装措施和注意事项。 展开更多
关键词 海底管道 铺设 自埋 阻流板 结构 安装
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油气管道与电力及通信线路的安全间距要求 被引量:10
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作者 程浩力 孙锐 +4 位作者 张连来 毛庞蛟 张晓海 夏茂进 池恒 《油气储运》 CAS 北大核心 2017年第12期1430-1435,共6页
油气管道在设计、施工及运营过程中经常遇到与电力及通信线路并行或交叉的情况。基于此,对不同法律及标准规范关于埋地油气管道与电力及通信线路并行或交叉敷设等安全间距的要求进行了对比分析,结果表明:对电力线路及通信线路与油气管... 油气管道在设计、施工及运营过程中经常遇到与电力及通信线路并行或交叉的情况。基于此,对不同法律及标准规范关于埋地油气管道与电力及通信线路并行或交叉敷设等安全间距的要求进行了对比分析,结果表明:对电力线路及通信线路与油气管道安全间距的要求因针对性不同而导致具体要求并不相同,需要设计及施工人员综合考虑油气管道实际情况设定有效间距。以某长输管道线路设计及施工中安全间距的设置为例,针对相关法律及标准规范的规定提出了改进建议。 展开更多
关键词 油气管道 架空 电力线路 通信线路 敷设 伴行 安全间距
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Nutritional modulation of health, egg quality and environmental pollution of the layers 被引量:8
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作者 Jing Wang Hongyuan Yue +2 位作者 Shugeng Wu Haijun Zhang Guanghai Qi 《Animal Nutrition》 SCIE 2017年第2期91-96,共6页
World egg production and consumption have been increasing for the past decades. Traditional strategies in poultry nutrition have made vital contributions to this great growth in quantity. However, current global issue... World egg production and consumption have been increasing for the past decades. Traditional strategies in poultry nutrition have made vital contributions to this great growth in quantity. However, current global issues should be considered in modern egg production such as growing populations and food security, food safety and quality, limited resources and environmental problems. The development of knowledge of poultry nutrition and modern biotechnology provides novel nutritional approaches to closely fit the requirement of pullets and laying hens, which will consequently decrease the nutrition excretion and maintain the lower cost of feed. Nutrition has also been widely accepted as a strategy to influence health and diseases of laying hens. The maintenance of good health is an important prerequisite for improving productivity and egg quality. In addition, there are many measures and strategies for minimizing the incidence of egg defects and providing a choice of lifestyle to enhance human health. This paper reviews current research progress on developing innovative technologies and strategies to maximize animal health and performance, improve the quality of egg products and minimize pollution caused by poultry production. 展开更多
关键词 Nutrient requirement Nutritional modulation PULLET laying hen
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Antimicrobial peptides as a feed additive alternative to animal production, food safety and public health implications: An overview 被引量:9
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作者 Raiza F.Silveira Cesar A.Roque-Borda Eduardo F.Vicente 《Animal Nutrition》 SCIE CSCD 2021年第3期896-904,共9页
In the last few years,feed additives have been used in animal nutrition to improve nutrient utilization,health parameters and animal performance.However,the use of antibiotics as feed additives has allowed the occurre... In the last few years,feed additives have been used in animal nutrition to improve nutrient utilization,health parameters and animal performance.However,the use of antibiotics as feed additives has allowed the occurrence of antimicrobial resistance(AMR),which can bring as a consequence,an increase in the morbidity and mortality of diseases that were previously treatable with antibiotics.In this context,antimicrobial peptides(AMP)have appeared as a promising strategy because they have multiple bio-logical activities and represent a powerful strategy to prevent the development of resistant microor-ganisms.Despite the small number of studies applied in vivo,AMP appear as a potent alternative to the use of antibiotics in animal nutrition,due to an increase in feed efficiency and the prevention/treatment of some animal diseases.This review discusses the problems associated with antimicrobial resistance and the use of AMP as a strong candidate to replace conventional antibiotics,mainly in the animal industry. 展开更多
关键词 ADDITIVE Antimicrobial peptide BROILER CATTLE laying hen PIG
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2BMK―1/3型穴播式铺膜播种机的设计与试验 被引量:9
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作者 张世杰 《中国农机化学报》 北大核心 2013年第4期113-117,共5页
论述了2BMK―1/3型穴播式铺膜播种机主要技术参数的设计与计算及性能,该机可由29.4-44.1kW拖拉机悬挂,由液压控制升降,为了适应"渗水地膜"和"VVV"型种植模式的要求,设计了能一次性浅旋、开沟、铺膜、膜上覆土、镇压等项目作业。通... 论述了2BMK―1/3型穴播式铺膜播种机主要技术参数的设计与计算及性能,该机可由29.4-44.1kW拖拉机悬挂,由液压控制升降,为了适应"渗水地膜"和"VVV"型种植模式的要求,设计了能一次性浅旋、开沟、铺膜、膜上覆土、镇压等项目作业。通过性能与生产试验表明,各项指标均达到设计要求。 展开更多
关键词 穴播式 铺膜 播种机
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Effect of supplementing layer hen diet with phytogenic feed additives on laying performance, egg quality, egg lipid peroxidation and blood biochemical constituents 被引量:7
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作者 Reham Abou-Elkhair Shaimaa Selim Eman Hussein 《Animal Nutrition》 2018年第4期394-400,共7页
This study was conducted to evaluate the effects of supplementing laying hen diet with phytogenic additives on laying performance, egg quality, blood constituents and egg lipid peroxidation. Two hundred Lohmann Brown ... This study was conducted to evaluate the effects of supplementing laying hen diet with phytogenic additives on laying performance, egg quality, blood constituents and egg lipid peroxidation. Two hundred Lohmann Brown Lite laying hens were randomly allotted to 4 dietary treatments: control(without phytogenic additive), fennel seeds(5 g/kg), black cumin seeds(5 g/kg) and hot red pepper(5 g/kg).Each of the 4 diets was fed to 5 replicates of 10 hens for 8 weeks. No significant differences were observed in body weight or feed intake between the groups. Dietary inclusion of fennel followed by red pepper improved(P < 0.05) egg weight, egg production, egg mass and feed conversion ratio compared with control. Higher yolk shape index, shell and albumen weight percentages and Haugh unit(P < 0.05)were recorded in the fennel supplemented group compared with control. The egg yolk color score increased by the addition of fennel or hot red pepper in laying hen diets compared with control. The inclusion of black cumin or hot red pepper decreased serum and egg yolk cholesterol and malondialdehyde concentrations(P < 0.05) compared with control. Serum aspartate aminotransferase concentration was lower in black cumin group(P < 0.05) than in other treatments. In conclusion, the best laying performance and egg quality were obtained by dietary inclusion of fennel, followed by hot red pepper and black cumin. Dietary supplementation of black cumin or red pepper may lead to the development of low-cholesterol concentration and better antioxidant capacity of eggs. 展开更多
关键词 Phytogenic additives EGG quality HEPATOPROTECTIVE activity Lipid PEROXIDATION Cholesterol laying HENS
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建筑工程中硬质阻燃型塑料电气管道的性能研究及敷设应用 被引量:8
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作者 林雅莲 《塑料工业》 CAS CSCD 北大核心 2016年第12期99-102,共4页
硬质阻燃型聚氯乙烯塑料电气管道由于具有良好的阻燃性能而被广泛应用于建筑工程施工中,以硅系阻燃剂有机蒙脱土、金属系阻燃剂氢氧化镁、磷系阻燃剂聚磷酸铵为例,对其阻燃型复合物的制备方法和性能进行探究。结果证明阻燃效果:氢氧化镁... 硬质阻燃型聚氯乙烯塑料电气管道由于具有良好的阻燃性能而被广泛应用于建筑工程施工中,以硅系阻燃剂有机蒙脱土、金属系阻燃剂氢氧化镁、磷系阻燃剂聚磷酸铵为例,对其阻燃型复合物的制备方法和性能进行探究。结果证明阻燃效果:氢氧化镁>有机蒙脱土>聚磷酸铵;拉伸强度:聚磷酸铵>有机蒙脱土>氢氧化镁;断裂伸长率:氢氧化镁>聚磷酸铵>有机蒙脱土。同时建筑工程中电气管道施工复杂,从施工前准备工作到敷设施工流程进行具体说明,包括工程审计、设计施工流程、主体结构施工和二次结构施工。 展开更多
关键词 建筑工程 聚氯乙烯树脂 阻燃性能 敷设
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