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Estimation of Genetic Parameters for Live Weight in South African Holstein Cattle
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作者 Nokuthula Innocentia Ramatsoma Cuthbert Baldwin Banga +1 位作者 Khoboso Christina Lehloenya Rory Gibson 《Open Journal of Animal Sciences》 2015年第3期242-248,共7页
Cow live weight is of economic importance in dairy production;however, it is not included in the selection objective for South African dairy cattle. Variance components estimates are a prerequisite to incorporating a ... Cow live weight is of economic importance in dairy production;however, it is not included in the selection objective for South African dairy cattle. Variance components estimates are a prerequisite to incorporating a trait in the breeding objective. Variance components were estimated for live weight of lactating Holstein cows on two South African dairy herds. Live weight records on 9843 lactating cows, collected over a period of three years, were used. An analysis of variance was carried out to determine fixed effects to include in the model by the least squares method, using the Generalised Linear Models procedure of the Statistical Analysis System. Variance components were estimated by the Restricted Maximum Likelihood procedure using the ASREML programme. A high heritability estimate of 0.74 ± 0.19 is found, which suggests that there is scope for significant response to selection on live weight in the South African Holstein cattle population. A repeatability estimate of 0.86 was obtained. These results form the basis for incorporating live weight in the breeding objective for South African Holstein cattle. Further work, however, needs to be done to develop estimates based on a representative sample of the whole population, as the current study is based on data from only two herds. 展开更多
关键词 live weight BREEDING Objective Variance Components HERITABILITY DAIRY COWS
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Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions 被引量:8
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作者 Seung Duk Lee Seong Hoon Kim +2 位作者 Young-Kyu Kim Soon-Ae Lee Sang-Jae Park 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2014年第1期18-24,共7页
BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate wh... BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. METHODS: From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7%(group A), 27 had a GRWR of ≥0.7%, 【0.8%(group B), and 267 had a GRWR of more than and equal to 0.8%(group C). Medical records, including recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. RESULTS: The baseline demographics showed low model for end-stage liver disease score(mean 16.3±8.9) and high percentage of hepatocellular carcinoma(231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For smallforsize syndrome, there were 3(13.0%) in group A, 1(3.7%) in group B, and 2 patients(0.7%) in group C(P【0.001). Hepatic artery thrombosis was more frequently observed in group A than in groups B and C(8.7% vs 3.7% vs 1.9%, P=0.047). However, among the three groups, graft survival rates at 1 year(100% vs 96.3% vs 93.6%) and 3 years(91.7% vs 73.2% vs 88.1%) were not different(P=0.539). In laboratory measurements,there was no group difference in total bilirubin and albumin. However, prothrombin time was longer in group A within postoperative 1 week and platelet count was lower in groups A and B within postoperative 1 month. CONCLUSION: A GRWR lower to 0.7% is safe and does not need to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score. 展开更多
关键词 graft-to-recipient weight ratio living donor liver transplantation small-for-size graft small-for-size syndrome
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Living donor liver transplantation with body-weight more or less than 10 kilograms 被引量:2
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作者 Sheng-Chun Yang Chia-Jung Huang +8 位作者 Chao-Long Chen Chih-Hsien Wang Shao-Chun Wu Tsung-Hsiao Shih Sin-Ei Juang Ying-En Lee Bruno Jawan Yu-Feng Cheng Kwok-Wai Cheng 《World Journal of Gastroenterology》 SCIE CAS 2015年第23期7248-7253,共6页
AIM: To compare the outcomes of pediatric patients weighing less than or more than 10 kg who underwent liver transplantation.METHODS: Data for 196 pediatric patients who underwent living donor liver transplantation be... AIM: To compare the outcomes of pediatric patients weighing less than or more than 10 kg who underwent liver transplantation.METHODS: Data for 196 pediatric patients who underwent living donor liver transplantation between June 1994 and February 2011 were reviewed retrospectively.The information for each patient was anonymized and de-identified before analysis. The data included information regarding the pre-transplant conditions, intraoperative fluid replacement and outcomes for each patient. The 196 patients were divided into two groups: those with body weights of less than 10 kg were included in group 1(G1; n =101), while those with body weights of more than 10 kg were included in group 2(G2; n = 95). For each group, the patients' ages, body weights, heights,pediatric end stage liver disease scores, anesthesia times, and warm and cold ischemic times were analyzed. In addition, between-group comparisons were also made. Mann-Whitney U tests were used to compare all the variables except for complications and survival rates, which were analyzed using χ 2 tests and Kaplan-Meier tests, respectively.RESULTS: The general medical conditions of the G1patients were worse than those of the G2 patients, as shown by the higher pediatric end stage liver disease scores and poorer Z-scores. In addition, the preoperative Hb and serum albumin levels were all lower for the G1 patients than for the G2 patients. The G1 patients also had significantly more intraoperative blood loss than the G2 patients. In addition, the intraoperative fluid requirements for the G1 patients,including leukocyte poor red blood cell transfusions,5% albumin infusions and crystalloid infusions, were significantly higher than those for the G2 patients. The risk of intraoperative portal vein thrombosis was higher for the patients in G1 than for those in G2. However,the one-year survival rates(95.9% and 96.8% for G1 and G2, respectively) and three-year survival rates(94.9% and 94.6% for G1 and G2, respectively) for both groups were similar.CONCLUSION: Patients weighing less than 10 kg typically have poorer conditions, but their survival rates are comparable to those of children weighing more than 10 kg. 展开更多
关键词 PEDIATRIC Body weight Pre-transplantcondition Fluid LIVING DONOR liver TRANSPLANTATION OUTCOME
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使用平均路径的一种新Live-wire算法 被引量:1
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作者 周頔 孙俊 李晓光 《计算机工程与应用》 CSCD 2013年第22期185-189,222,共6页
在传统Live-wire算法中,两个人工选定节点之间的最优路径被定义为具有最小累计能量的路径。因此传统live-wire算法在分割边缘转折剧烈的物体时,为了保证分割的正确性就需要人工添加较多的节点,从而增加整个分割过程的耗时。提出一种基... 在传统Live-wire算法中,两个人工选定节点之间的最优路径被定义为具有最小累计能量的路径。因此传统live-wire算法在分割边缘转折剧烈的物体时,为了保证分割的正确性就需要人工添加较多的节点,从而增加整个分割过程的耗时。提出一种基于可控平均代价路径的新型Live-wire算法,并从理论上证明,传统live-wire算法其实是提出的新型算法的一种特例。实验表明,新型Live-wire算法与传统算法相比,能在保证精度的同时减少人工设定的节点个数,从而加快整个分割过程的速度。 展开更多
关键词 分割 live-wire算法 平均代价路径 带权重的Canny边缘
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Experiences of Low Gestational Weight Gain: A Phenomenological Study with Pregnant Women 被引量:1
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作者 Cynthia L. Murray Sherrill A. Conroy 《Health》 2014年第19期2611-2623,共13页
Low maternal, gestational weight gain is associated with preterm birth, intrauterine growth restriction, low birthweight, small-for-gestational-age infants, neural tube defects, infant death, failure to initiate breas... Low maternal, gestational weight gain is associated with preterm birth, intrauterine growth restriction, low birthweight, small-for-gestational-age infants, neural tube defects, infant death, failure to initiate breastfeeding, and childhood asthma. The advantage of qualitative research is it can provide valuable insights for health care professionals into the experience and perceptions of low gestational weight gain from the vantage point of women with first-hand lived experience. In this Heideggarian interpretive phenomenological study, the meaning and experiences of weight gain for pregnant women with low gestational weight gain were explored. Data were collected through interviews with 10 pregnant women from Atlantic Canada. Conroy’s pathway for interpretive phenomenology was utilized. A hermeneutical spiral of interpretation identified six patterns or major themes: confronting one’s mortality;defending oneself against a permanent metamorphosis into a stranger;playing with fire and brimstone;slipping under the radar;trying to find peace;and riding an emotional roller coaster. The findings point to a war that is being waged over pregnant bodies with respect to weight that leaves pregnant women fending for themselves, apparently with little help from their health care providers. Implications of the findings for health practice, education, and research are discussed. 展开更多
关键词 Embodiment/Bodily Experiences Heideggarian Interpretive PHENOMENOLOGY liveD Experience PREGNANCY weight GAIN
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“It’s a Wild Ride”: A Phenomenological Exploration of High Maternal, Gestational Weight Gain
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作者 Cynthia L. Murray 《Health》 2014年第18期2541-2552,共12页
High maternal, gestational weight gain is associated with high birthweight, large-for-gestational-age birthweights, cesarean delivery, child overweight, and short- and long-term postpartum weight retention. In this ph... High maternal, gestational weight gain is associated with high birthweight, large-for-gestational-age birthweights, cesarean delivery, child overweight, and short- and long-term postpartum weight retention. In this phenomenological study, the meaning and experiences of weight gain for pregnant women with high gestational weight gain were investigated. Data were collected through interviews with pregnant women from Atlantic Canada. van Manen’s method of phenomenology was utilized. The data analysis revealed four patterns or major themes: being caught off guard;losing your bearings;hanging on for dear life;and hoping for health. The participants experienced their gestational weight gain as an unexpected “wild ride” that they could not control. The findings highlight the need for health care professionals to provide pregnant women with more support concerning gestational weight gain. 展开更多
关键词 Embodiment/Bodily Experiences PHENOMENOLOGY liveD Experience Pregnancy weight Gain
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Outcomes of adult patients adopting small-for-size grafts in living donor liver transplantation: A systematic review and meta-analysis 被引量:1
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作者 Yue Yan Dao-Feng Zheng +1 位作者 Jun-Liang Pu Zhong-Jun Wu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第3期206-213,共8页
Background: Small-for-size graft(SFSG) has emerged as one of the very contentions in adult-to-adult living donor liver transplantation(LDLT) as a certain graft size is related to recipients’ prognosis. Graftto-recipi... Background: Small-for-size graft(SFSG) has emerged as one of the very contentions in adult-to-adult living donor liver transplantation(LDLT) as a certain graft size is related to recipients’ prognosis. Graftto-recipient weight ratio(GRWR)≥0.8% was considered as a threshold to conduct LDLT. However, this also has been challenged over decades as a result of technique refinements. For a better understanding of SFSG in practice, we conducted this meta-analysis to compare the perioperative outcomes and long-term outcomes between patients adopting the grafts with a lower volume(GRWR < 0.8%, SFSG group) and sufficient volume(GRWR ≥ 0.8%, non-SFSG group) in adult-to-adult LDLT. Data sources: The studies comparing recipients adopting graft with a GRWR < 0.8% and ≥ 0.8% were searched by three authors independently in Pub Med, Web of Science, Embase, the Cochrane Library, MEDLINE and Google Scholar databases until September 2018 and data were analyzed by RevMan 5.3.5. Results: Sixteen studies with a total of 3272 subjects were included in this meta-analysis. In terms of small-for-size syndrome(SFSS), no significant difference was found in subjects enrolled after year 2010(before 2010, OR = 3.00, 95% CI: 1.69–5.35, P = 0.0002;after 2010, OR = 1.23, 95% CI: 0.79–1.90, P = 0.36;P for interaction: 0.02). There was no significant difference in operative duration, blood loss, cold ischemia time, biliary complications, acute rejection, postoperative bleeding, hospitalization time, perioperative mortality, and 1-, 3-and 5-year overall survival rates between two groups. Conclusions: This meta-analysis suggested that adopting SFSG in adult LDLT has comparable outcomes to those with non-SFSG counterparts since 2010. 展开更多
关键词 LIVING DONOR liver TRANSPLANTATION Graft-to-recipient weight ratio Small-for-size GRAFT
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THE RELATION OF SEQUENCE DISTRIBUTIONS OF S-SBR TO ITS MOLECULAR WEIGHT DISTRIBUTIONS
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作者 陈贤益 应圣康 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1991年第4期283-288,共6页
The relationship between sequence distributions and molecular weight distributions of S-SBR, obtained from styrene and butadiene anionic copolymerization at various conversions with THF/Li^+ as an initiator has been s... The relationship between sequence distributions and molecular weight distributions of S-SBR, obtained from styrene and butadiene anionic copolymerization at various conversions with THF/Li^+ as an initiator has been studied by ^(13)C-NMR,GPC. The results showed that the molecular weight distributions of the copolymer couldbe correlated sophisticatedly to the binary sequcne distributions or the monomer unit distributions of the copolymer in a corrected Poisson's distribution from. 展开更多
关键词 Molecular weight distributions Sequence distributions BUTADIENE STYRENE Living copolymerization
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Splenectomy in living donor liver transplantation and risk factors of portal vein thrombosis 被引量:5
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作者 Nobuhiko Kurata Yasuhiro Ogura +3 位作者 Satoshi Ogiso Yasuharu Onishi Hideya Kamei Yasuhiro Kodera 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第4期337-342,共6页
Background:Graft inflow modulation(GIM)during adult-to-adult living donor liver transplantation(LDLT)is a common strategy to avoid small-for-size syndrome,and some transplant surgeons attempt small size graft strategy... Background:Graft inflow modulation(GIM)during adult-to-adult living donor liver transplantation(LDLT)is a common strategy to avoid small-for-size syndrome,and some transplant surgeons attempt small size graft strategy with frequent GIM procedures,which are mostly performed by splenectomy,in LDLT.However,splenectomy can cause serious complications such as portal vein thrombosis and overwhelming postsplenectomy infection.Methods:Forty-eight adult-to-adult LDLT recipients were enrolled in this study and retrospectively reviewed.We applied the graft selection criteria,which routinely fulfill graft-to-recipient weight ratio≥0.8%,and consider GIM as a backup strategy for high portal venous pressure(PVP).Results:In our current strategy of LDLT,splenectomy was performed mostly due to hepatitis C and splenic arterial aneurysms,but splenectomy for GIM was intended to only one patient(2.1%).The final PVP values≤20 mmHg were achieved in all recipients,and no significant difference was observed in patient survival or postoperative clinical course based on whether splenectomy was performed or not.However,6 of 18 patients with splenectomy(33.3%)developed postsplenectomy portal vein thrombosis(PVT),while none of the 30 patients without splenectomy developed PVT after LDLT.Splenectomy was identified as a risk factor of PVT in this study(P<0.001).Our study revealed that a lower final PVP could be risk factor of postsplenectomy PVT.Conclusions:Using sufficient size grafts was one of the direct solutions to control PVP,and allowed GIM to be reserved as a backup procedure.Splenectomy should be avoided as much as possible during LDLT because splenectomy was found to be a definite risk factor of PVT.In splenectomy cases with a lower final PVP,a close follow-up is required for early detection and treatment of PVT. 展开更多
关键词 Living donor liver transplantation SPLENECTOMY PORTAL VENOUS pressure Graft-to-recipient weight ratio PORTAL VEIN THROMBOSIS
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保存时间对黑水虻幼虫体重和营养物质的影响
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作者 鹿震涛 欧阳晨晨 +3 位作者 周雅豪 张云婷 闻治国 吴学壮 《饲料工业》 CAS 北大核心 2024年第2期8-12,共5页
试验旨在阐明不同日龄黑水虻幼虫活体保存期间体重和营养物质的变化规律。试验选取10日龄、12日龄、14日龄幼虫各6 kg,每个龄期为1个处理,每个处理6个重复,每个重复1 kg,其中3个重复每天中午称量幼虫重量,用于测定体重损失;另外3个重复... 试验旨在阐明不同日龄黑水虻幼虫活体保存期间体重和营养物质的变化规律。试验选取10日龄、12日龄、14日龄幼虫各6 kg,每个龄期为1个处理,每个处理6个重复,每个重复1 kg,其中3个重复每天中午称量幼虫重量,用于测定体重损失;另外3个重复的幼虫在同样环境下存放,分别于第5、10、15、20天,每个重复取50 g幼虫称重,烘干后测定营养物质含量。结果显示:12日龄和14日龄幼虫鲜重第20天绝对损失均在50%左右。黑水虻幼虫活体保存15 d幼虫干物质含量显著高于保存5 d和10 d幼虫干物质含量(P<0.05);12日龄、14日龄黑水虻幼虫第10天和第20天粗蛋白含量高于第5天和初始幼虫粗蛋白含量(P<0.05),在保存第15天粗蛋白含量最高;14日龄幼虫初始粗脂肪含量显著高于其他阶段。保存时间与日龄具有交互作用,保存时间×日龄能显著影响黑水虻幼虫的粗脂肪、干物质含量(P<0.05)。本研究揭示了黑水虻活体保存期间幼虫体内营养物质变化规律和消耗程度,本试验条件下,10日龄黑水虻幼虫进行运输和鲜活保存,且保存时间10 d内能获得较高的营养物质。 展开更多
关键词 保存时间 黑水虻 活体保存 重量损失 营养物质
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中国乡村人居环境韧性评价及障碍因素分析
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作者 朱彤瑶 蒋国河 曹俊文 《生态经济》 北大核心 2024年第11期89-96,共8页
论文从乡村人居环境韧性内涵出发,构建乡村人居环境韧性评价指标体系,并将其转换为基于系统属性的乡村人居环境韧性评价指标体系,分析2010—2020年中国乡村人居环境韧性演变特征,识别中国乡村人居环境韧性障碍因素。研究结果表明:中国... 论文从乡村人居环境韧性内涵出发,构建乡村人居环境韧性评价指标体系,并将其转换为基于系统属性的乡村人居环境韧性评价指标体系,分析2010—2020年中国乡村人居环境韧性演变特征,识别中国乡村人居环境韧性障碍因素。研究结果表明:中国乡村人居环境韧性指数总体呈现波动上升态势,但各区域变动态势不尽相同,乡村人居环境韧性水平变动与经济发展格局基本一致。乡村人居环境不同子系统韧性呈现不同的变动态势,社会子系统韧性水平最高,经济子系统韧性水平最低,且呈现持续下滑态势。工程子系统韧性障碍度是乡村韧性水平提升的最主要障碍子系统,资源禀赋、农业生产、环境治理、居住条件和科技创新是中国乡村人居环境韧性提升的共同障碍要素。根据障碍度测算结果将中国各省份划分为环境治理与生态维护障碍型、资源禀赋与环境治理障碍型、居住条件与区域交通障碍型、农业生产条件与居住条件障碍型,并针对不同类型的特点提出不同的对策。 展开更多
关键词 乡村人居环境 韧性 熵权法 评价 障碍度
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星形多臂丁苯共聚物的分子结构设计与合成
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作者 宋雨骏 赵忠夫 +3 位作者 李博涵 李倩 李龙昊 张春庆 《合成橡胶工业》 CAS 2024年第5期367-372,共6页
以正丁基锂为引发剂、苯乙烯与丁二烯为单体、双四氢糠丙烷为极性结构调节剂、六氯乙硅烷为偶联剂,采用活性负离子聚合技术设计并合成了一系列具有星形结构的多臂丁苯共聚物(S-g-SSB-6)。使用凝胶渗透色谱分析了S-g-SSB-6的分子量及其... 以正丁基锂为引发剂、苯乙烯与丁二烯为单体、双四氢糠丙烷为极性结构调节剂、六氯乙硅烷为偶联剂,采用活性负离子聚合技术设计并合成了一系列具有星形结构的多臂丁苯共聚物(S-g-SSB-6)。使用凝胶渗透色谱分析了S-g-SSB-6的分子量及其分布、偶联臂数和偶联效率,使用旋转流变仪测试了S-g-SSB-6、以SiCl_(4)为偶联剂的星形多臂丁苯共聚物及线型结构丁苯共聚物(L-SSB)的流变性能,并考察了支链长度和支链柔顺性对S-g-SSB-6流变性能的影响。结果表明,S-g-SSB-6的偶联臂数达到4.1、偶联效率均大于80%;相同重均分子量下S-g-SSB-6的熔体黏度较L-SSB更低、流体流动性更好;当支化度相同时,S-g-SSB-6的熔体黏度随着单臂分子量和分子链刚性的增加而增大。 展开更多
关键词 丁苯共聚物 星形支化 活性负离子聚合 六氯乙硅烷 偶联反应 分子量及其分布
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辽宁省“三生”功能时空演变及其碳排放效应 被引量:1
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作者 黄栋 刘跃宗 +1 位作者 刘建宁 李一博 《水土保持通报》 CSCD 北大核心 2024年第1期421-431,共11页
[目的]探究辽宁省“三生”功能时空演变及其碳排放效应,为“双碳”目标下的国土空间规划提供依据。[方法]基于土地利用多功能性分类识别辽宁省国土“三生”功能,结合直接和间接排放因子法核算碳排放量,探索“三生”功能与碳排放量空间... [目的]探究辽宁省“三生”功能时空演变及其碳排放效应,为“双碳”目标下的国土空间规划提供依据。[方法]基于土地利用多功能性分类识别辽宁省国土“三生”功能,结合直接和间接排放因子法核算碳排放量,探索“三生”功能与碳排放量空间关系及其时空分异性,揭示“三生”功能时空演变的碳排放效应。[结果]①2005—2020年辽宁省“三生”功能空间分布格局总体变化不大,大部分地区以生产和生态功能为主,生活功能区扩张明显,各地级市中心与周边区域空间差异明显。②2005—2013年,辽宁省各县域碳排放量增长迅速,2013—2020年增速缓慢,但空间差异愈发显著,碳排放高值明显集中在沈阳市和大连市。③辽宁省“三生”功能与碳排放量空间布局及数量变化的相关性总体较强,但空间差异明显且影响因素复杂。[结论]辽宁省各县域需要在自然地理条件约束和经济社会发展需求引导下,在明确各自土地主导功能定位的基础上,依托自身区域优势与资源禀赋,加强区域协作,以实现全域碳减排。 展开更多
关键词 “三生”功能 时空演变 碳排放 地理加权回归 辽宁省
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胆甾醇基液晶功能化SBS弹性体的合成与性能研究
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作者 杨佳欣 王博 +2 位作者 马红卫 韩丽 李杨 《橡胶工业》 CAS 2024年第12期883-894,共12页
基于活性阴离子聚合方法,以苯乙烯和丁二烯为共聚单体,以四氯化硅为偶联剂,通过顺序加料法和星形偶联法,设计合成了不同数均相对分子质量(12.2~66.5 kg·mol^(-1))和组成的星形苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS),其相对分子质量... 基于活性阴离子聚合方法,以苯乙烯和丁二烯为共聚单体,以四氯化硅为偶联剂,通过顺序加料法和星形偶联法,设计合成了不同数均相对分子质量(12.2~66.5 kg·mol^(-1))和组成的星形苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS),其相对分子质量分布指数为1.03~1.20,并选取牌号为SBS-791,SBS-792,SBS-LG(数均相对分子质量为91.5~131.1 kg·mol^(-1),相对分子质量分布指数为1.07~1.39)的商品化线性SBS,将设计合成的硅氢末端的胆甾醇基液晶单体[Chol-SiH(M)]接枝到SBS的聚丁二烯嵌段上,制备了结构和接枝密度相似、相对分子质量和组成不同的胆甾醇基液晶功能化SBS弹性体(SBS-LC)。采用配置四检测器的凝胶渗透色谱仪和氢核磁共振仪对SBS及SBS-LC的相对分子质量和微观结构进行了分析,采用偏光显微镜和差示扫描量热仪对SBS-LC的液晶织构和热性能进行了分析,建立了SBS-LC的结构与性能的构-效关系,为液晶功能化高分子材料的设计与应用打下了基础。 展开更多
关键词 活性阴离子聚合 苯乙烯-丁二烯-苯乙烯嵌段共聚物 液晶弹性体 相对分子质量 液晶织构 热性能
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高温带电作业屏蔽服内胆织物优选及工效验证
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作者 李红彦 薛萧昱 +2 位作者 张丹 王敏 高阳 《服装学报》 北大核心 2024年第6期500-506,共7页
针对高温带电作业屏蔽服内胆织物筛选存在主观性和模糊性的问题,引入熵权-秩和比法定量筛选最优织物,以改善屏蔽服的热湿舒适性。选取6款导湿织物为研究对象,采用熵权-秩和比法从导热性能、吸湿速干性能、接触瞬间凉感、动态水分管理能... 针对高温带电作业屏蔽服内胆织物筛选存在主观性和模糊性的问题,引入熵权-秩和比法定量筛选最优织物,以改善屏蔽服的热湿舒适性。选取6款导湿织物为研究对象,采用熵权-秩和比法从导热性能、吸湿速干性能、接触瞬间凉感、动态水分管理能力等方面进行重要度排序与分档,筛选出综合性能最优的织物用于屏蔽服内胆,并通过工效学实验验证研究方法的有效性。结果表明,2#涤丙双层单向导湿织物综合性能最优,适合作为单导区织物。进一步研究发现,增加内胆对屏蔽服整体活动工效性无显著影响;现役屏蔽服在膝盖和臀部区域的活动工效性有待改进。研究结果验证了熵权-秩和比法在屏蔽服内胆织物优选中的可行性,为后续高温带电作业屏蔽服的研发与优化提供了有效手段。 展开更多
关键词 高温环境 带电作业屏蔽服 织物优选 工效实验 熵权-秩和比法
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氮磷钾及有机肥对马铃薯生长发育和干物质积累的影响 被引量:47
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作者 王国兴 徐福利 +2 位作者 王渭玲 于丹 王伟东 《干旱地区农业研究》 CSCD 北大核心 2013年第3期106-111,共6页
采取田间试验,探讨不同施肥处理对马铃薯生长发育及干物质积累的影响。结果表明,N1PKM处理(氮300 kg.hm-2,磷200 kg.hm-2,钾200 kg.hm-2,有机肥17.5 t.hm-2)的马铃薯叶片叶绿素含量最高,比对照处理的叶片叶绿素a、b、总量分别高出15.12%... 采取田间试验,探讨不同施肥处理对马铃薯生长发育及干物质积累的影响。结果表明,N1PKM处理(氮300 kg.hm-2,磷200 kg.hm-2,钾200 kg.hm-2,有机肥17.5 t.hm-2)的马铃薯叶片叶绿素含量最高,比对照处理的叶片叶绿素a、b、总量分别高出15.12%、18.18%和36.37%。施用磷肥有效促进了叶面积的增加,N1PKM、N1P、N1PK、P处理的叶面积比对照分别高出27.78%,24.57%,20.26%和20.16%。其中施用磷肥促进马铃薯根系生长的效果最明显,而单施钾肥、有机肥对根长发育的影响不明显。氮、磷、钾、有机肥配比施用可以促进马铃薯地上及地下部的生长,采用氮磷钾与有机肥配合施用时,马铃薯干物质累积总量N1PKM>N1PK>N1K>N1P。N1PKM处理的马铃薯生物量较对照显著提高了117.1%,可以作为旱地马铃薯的施肥方案。 展开更多
关键词 施肥配比 马铃薯 生长发育 干物质 生物量
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栉孔扇贝壳尺寸性状对活体重的影响效果分析 被引量:246
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作者 刘小林 常亚青 +2 位作者 相建海 宋坚 丁君 《海洋与湖沼》 CAS CSCD 北大核心 2002年第6期673-678,共6页
选取 65只 2岁龄栉孔扇贝 ,测定其壳长、壳厚、壳高、活体重、肉重、熟肉重 ,计算相关系数 ,采用通径分析方法计算了以贝壳性状为自变量对活体重作依变量的通径系数、决定系数及相关指数。结果表明 ,栉孔扇贝壳长、壳厚、壳高与活体重... 选取 65只 2岁龄栉孔扇贝 ,测定其壳长、壳厚、壳高、活体重、肉重、熟肉重 ,计算相关系数 ,采用通径分析方法计算了以贝壳性状为自变量对活体重作依变量的通径系数、决定系数及相关指数。结果表明 ,栉孔扇贝壳长、壳厚、壳高与活体重、净肉重、熟肉重的相关系数均达到极显著水平 (P <0 .0 1 ) ;壳高对活体重的直接影响 ( 0 .6682 )最大 ,是影响活体重的主要因素 ;壳长与活体重的相关程度很大 ,但对活体重的直接影响 ( 0 .2 5 5 9 )较小 ,主要通过壳高间接影响活体重 ,是影响活体重的次要因素 ;壳厚对活体重的直接影响 ( 0 .0 960 )最小 ;决定系数分析结果与通径分析结果有一致的变化趋势 ;所选贝壳性状与活体重的复相关指数为R2 =0 .8847;多元回归分析建立了壳长、壳厚、壳高估计活体重的回归方程为 :^Y =- 42 .1 331 + 3.1 60X1 + 3.5 2 5 3X2 + 7.692 0X3,为扇贝选种提供了理论依据和理想的测度指标。 展开更多
关键词 栉孔扇贝 壳尺寸性状 活体重 相关系数 壳长 壳厚 壳高
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鸡沙门氏菌弱毒冻干苗的研制 被引量:15
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作者 潘志明 焦新安 +7 位作者 黄金林 张小荣 孙林 刘文博 甘军纪 高崧 张如宽 刘秀梵 《中国预防兽医学报》 CAS CSCD 北大核心 2001年第6期444-447,共4页
由减毒鸡沙门氏菌 97A疫苗株作为制苗用菌种 ,经普通琼脂培养、冷冻真空干燥等工艺生产鸡沙门氏菌弱毒疫苗 4批 ,每批疫苗分别以免疫剂量接种 6日龄AA肉鸡 ,免疫第 14天时 ,用强毒株Sg9和Sp4攻击 ,免疫组死亡保护率均达 90 %以上。试验... 由减毒鸡沙门氏菌 97A疫苗株作为制苗用菌种 ,经普通琼脂培养、冷冻真空干燥等工艺生产鸡沙门氏菌弱毒疫苗 4批 ,每批疫苗分别以免疫剂量接种 6日龄AA肉鸡 ,免疫第 14天时 ,用强毒株Sg9和Sp4攻击 ,免疫组死亡保护率均达 90 %以上。试验结果表明 。 展开更多
关键词 鸡沙门氏菌弱毒苗 安全性 免疫效力 疫苗 冻干苗
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不同配伍酶制剂处理玉米秸秆对肉用绵羊生长性能和营养物质消化率的影响 被引量:16
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作者 王红梅 屠焰 +2 位作者 司丙文 聂明非 刁其玉 《中国农业科学》 CAS CSCD 北大核心 2016年第24期4806-4813,共8页
【目的】在以玉米秸秆为粗饲料的饲粮中添加不同配伍酶制剂,研究其对杜寒杂交肉羊生长性能和营养物质表观消化率的影响。【方法】选择400只月龄(3月龄)和体重(26.95±0.91kg)相近的杜寒杂交公羔羊,分为4组(每组100只、5个重复,每个... 【目的】在以玉米秸秆为粗饲料的饲粮中添加不同配伍酶制剂,研究其对杜寒杂交肉羊生长性能和营养物质表观消化率的影响。【方法】选择400只月龄(3月龄)和体重(26.95±0.91kg)相近的杜寒杂交公羔羊,分为4组(每组100只、5个重复,每个重复20只),即对照组(基础饲粮无添加酶制剂),处理组Ⅰ(基础饲粮+纤维素酶、β-葡聚糖酶和木聚糖酶复合酶制剂)、处理组Ⅱ(基础饲粮+纤维素酶、β-葡聚糖酶、木聚糖酶和果胶酶复合酶制剂)和处理组Ⅲ(基础饲粮+纤维素酶、β-葡聚糖酶、木聚糖酶、果胶酶和漆酶复合酶制剂);基础日粮为依据NRC(2007)配制精粗比4:6(第一期)和5:5(第二期)(DM基础)的TMR饲粮;将复合酶制剂干粉用清水稀释成4%的溶液,喷洒于秸秆表面与精料补充料,用TMR机充分混匀后直接饲喂,复合酶制剂添加量为1kg·t-1基础饲粮(风干基础);试验期为76d(预试期为10d,正试期为66d)。【结果】不同配伍酶制剂对平均日增重(ADG)和料重比具有显著的影响(P<0.05),而对干物质采食量(DMI)没有显著的影响(P=0.107)。处理组Ⅲ和处理组Ⅱ的ADG显著高于对照组和处理组Ⅰ(P<0.05),处理组Ⅲ和处理组Ⅱ的料重比显著低于对照组(P<0.05),而处理组Ⅲ与处理组Ⅱ或对照组与处理组Ⅰ之间ADG和料重比均没有显著差异(P>0.05)。另外,不同配伍酶制剂对日粮DM、OM、GE、NDF和ADF的表观消化率具有显著的影响(P<0.05),但对CP表观消化率没有显著影响(P>0.05)。处理组Ⅲ和处理组Ⅱ的DM、OM、GE、NDF消化率显著高于对照组和处理组Ⅰ(P<0.05),处理组Ⅲ的ADF消化率显著高于对照组(P<0.05)。而处理组Ⅲ与处理组Ⅱ或对照组与处理组Ⅰ之间各营养物质表观消化率没有显著差异(P>0.05),此外,4个组间CP表观消化率没有显著差异(P=0.166)。处理组Ⅲ的各营养物质(除CP外)表观消化率最高,与处理组Ⅱ相比,数值上占绝对优势,其中,DM和ADF消化率的提高幅度最大,与对照组相比分别提高11%和19%,同时,也具有较好的经济效益。【结论】不同配伍酶制剂处理秸秆型饲粮对育肥羊生长性能和营养物质消化率产生积极效应,处理组Ⅲ和处理组Ⅱ效果均显著,相比之下,处理组Ⅲ的效果更好,与对照相比,营养物质消化率提高11%,增重提高23.51%,饲料转化率提高26.36%,1kg增重饲料成本降低18.42%。 展开更多
关键词 育肥羊 复合酶制剂 秸秆 增重 消化率
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饲粮营养水平对三个地方品种鸡生长性能及屠体品质的影响 被引量:21
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作者 张顺珍 包承玉 +1 位作者 邵春荣 刘明智 《江苏农业学报》 CSCD 北大核心 1998年第3期174-178,共5页
采用饲养试验、屠宰测定和肉质分析的方法比较了3种不同营养水平饲粮对地方品种鸡(“泰和鸡”、“黑羽乌骨鸡”、“中型黄鸡”)生长性能和肉质的影响。各品种鸡被随机分成3组(Ⅰ、Ⅱ、Ⅲ),分别饲喂高、中、低3种能量和蛋白质水... 采用饲养试验、屠宰测定和肉质分析的方法比较了3种不同营养水平饲粮对地方品种鸡(“泰和鸡”、“黑羽乌骨鸡”、“中型黄鸡”)生长性能和肉质的影响。各品种鸡被随机分成3组(Ⅰ、Ⅱ、Ⅲ),分别饲喂高、中、低3种能量和蛋白质水平的饲粮。结果表明,含较高能量和蛋白质的Ⅰ组饲粮可提高黑羽乌骨鸡的增重速度,在4周龄前尤其明显;泰和鸡4周龄体重Ⅰ组、Ⅱ组显著高于Ⅲ组(P<0.05);中型黄鸡的增重以饲喂中等营养水平日粮的Ⅱ组稍高,但差异不显著(P>0.05)。3个品种试验鸡的饲料转化率都以使用高营养水平的Ⅰ组日粮最优,单位增重耗料最少、单位增重花费的饲料成本也最低。饲粮营养水平对肉质有一定影响,低能低蛋白饲粮组鸡的肉质优于高能高蛋白日粮组鸡,各组试验鸡的肉质测定值均在优质鸡肉质标准范围之内。 展开更多
关键词 地方品种 饲粮营养水平 增重 屠体品质
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