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ABO血型基因第7外显子695 T>C突变导致Bw11亚型的研究
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作者 周丽华 沈茹 +3 位作者 屈柯暄 王爱华 陈有会 袁志敏 《诊断学理论与实践》 2024年第4期392-397,共6页
目的:在中国彝族人群中发现罕见的ABO*BW.11/ABO*O.01.02血型基因亚型,探讨ABO*BW.11/ABO*O.01.02血型血清学特点、分子机制及遗传背景。方法:先证者为孕产妇,25岁,入院常规检测显示其ABO正反定型不符,在常规ABO血型血清学无法准确鉴定... 目的:在中国彝族人群中发现罕见的ABO*BW.11/ABO*O.01.02血型基因亚型,探讨ABO*BW.11/ABO*O.01.02血型血清学特点、分子机制及遗传背景。方法:先证者为孕产妇,25岁,入院常规检测显示其ABO正反定型不符,在常规ABO血型血清学无法准确鉴定的情况下,对ABO基因第1-7外显子采用Sanger法进行测序分析,并利用野生型B糖基转移酶氨基酸系列同源建模,预测该位点突变对B糖基转移酶结构和功能的影响。结果:先证者及家系成员血型血清学结果与常见B亚型均不相符;ABO基因测序结果显示,先证者及家系成员4代共7人均存在ABO血型基因第7外显子存在c.695T>C错义突变,导致B糖基转移酶第232位亮氨酸被脯氨酸替换。同源建模显示,突变影响了蛋白质的肽键和氢键,导致其结构和功能发生改变,B糖基转移酶的活性降低,导致B抗原表达减弱。结论:ABO等位基因出现第7外显子c.695T>C.P.leu 232 Pro点突变是形成ABO*BW.11/ABO*O.01.02亚型的分子基础,此突变在此家系多成员中稳定遗传。 展开更多
关键词 ABO亚型 基因突变 bw亚型 B糖基转移酶
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A1Bw亚型中多重抗体漏检的临床研究
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作者 邹昕 范小杰 《检验医学与临床》 CAS 2024年第11期1651-1654,共4页
目的分析1例A1Bw亚型样本的血清学和分子生物学特征及交叉配血不合原因。方法采用试管法对该样本进行ABO血型血清学检测、吸收放散试验、唾液血型物质检测、酸化血清试验、ABO基因第1~7外显子扩增产物基因测序。以“ABO亚型”和“不规则... 目的分析1例A1Bw亚型样本的血清学和分子生物学特征及交叉配血不合原因。方法采用试管法对该样本进行ABO血型血清学检测、吸收放散试验、唾液血型物质检测、酸化血清试验、ABO基因第1~7外显子扩增产物基因测序。以“ABO亚型”和“不规则抗-B/抗-A抗体”为关键词,对中国知网数据库2020年1月至2023年8月发表的文献进行文献检索。结果该样本血清学表型为cisAB/A或ABx,同时血清中产生同种抗-Lea、抗-E抗体伴不规则抗-B抗体。ABO基因序列分析结果显示,ABO*A1.02/B.01杂合,且第7外显子发生c.721C/T基因突变,最终该血型判定为ABO*A1.02/BW.03基因型。文献检索结果显示,共检索到文献42篇,排除分子技术、肿瘤疾病等文献,最终纳入18篇文献。该文主要从亚型中不规则抗体检测的角度出发,重点叙述多重抗体漏检分析,总结当存在ABO血型以外的不规则抗体时,亚型中的不规则抗-B/抗-A抗体的检测流程。结论血清学试验结合分子生物学方法可更准确鉴定ABO亚型,正确鉴定亚型中不规则抗体是保障输血安全的前提。 展开更多
关键词 ABO亚型 不规则抗-B/抗-A抗体 抗-Lea抗体 抗-E抗体 ABO*A1.02/bw.03
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超声冲击对SMA490BW耐候钢焊接接头腐蚀疲劳的影响 被引量:1
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作者 童第华 王乃境 +2 位作者 丛家慧 高倩倩 陈勃 《有色金属工程》 CAS 北大核心 2024年第3期1-9,共9页
采用USP-300超声表面加工装置对SMA490BW耐候钢表面进行超声冲击处理。研究超声冲击前后试件的显微组织、显微硬度和残余应力,比较超声冲击前后SMA490BW耐候钢焊接接头的腐蚀速率和腐蚀疲劳寿命。通过光学显微镜观察超声冲击后SMA490BW... 采用USP-300超声表面加工装置对SMA490BW耐候钢表面进行超声冲击处理。研究超声冲击前后试件的显微组织、显微硬度和残余应力,比较超声冲击前后SMA490BW耐候钢焊接接头的腐蚀速率和腐蚀疲劳寿命。通过光学显微镜观察超声冲击后SMA490BW耐候钢的显微组织,采用测试仪器测试焊接接头的表面硬度和残余应力,分析超声冲击提高SMA490BW耐候钢抗腐蚀性及其疲劳寿命的机理。结果表明,超声冲击处理能使材料表层晶粒细化形成致密的塑性变形层,提高显微硬度,并在材料表面引入有效的残余压应力,降低腐蚀速率,减小失重量。同时,超声冲击处理后裂纹扩展路径变得更加复杂,裂纹扩展速率降低,焊接接头腐蚀疲劳寿命得到提高。 展开更多
关键词 SMA490bw耐候钢 焊接接头 腐蚀速率 疲劳寿命
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PE-BW-SiO_(2)复合包装膜对草鱼保鲜效果的研究
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作者 李娟华 王红蕾 +3 位作者 陈国健 高南 仲芸芸 肖乃玉 《包装工程》 CAS 北大核心 2024年第9期34-44,共11页
目的开发一种具有优良理化性能,并能有效应用于草鱼保鲜的新型活性包装膜。方法采用聚乙烯为基膜材料,以蜂蜡和纳米SiO_(2)为活性成分,采用熔融共混和造粒吹膜工艺制备PE-BW-SiO_(2)复合包装膜。测定包装膜的力学性能、阻隔性能和疏水性... 目的开发一种具有优良理化性能,并能有效应用于草鱼保鲜的新型活性包装膜。方法采用聚乙烯为基膜材料,以蜂蜡和纳米SiO_(2)为活性成分,采用熔融共混和造粒吹膜工艺制备PE-BW-SiO_(2)复合包装膜。测定包装膜的力学性能、阻隔性能和疏水性能,并研究它在4℃贮藏条件下对草鱼的保鲜效果。结果通过添加BW-SiO_(2)活性成分,包装膜的力学性能、阻隔性能和疏水性能得到提高。其中,BW-SiO_(2)添加量(质量分数)为2%的包装膜的力学性能、阻隔性能等综合性能达到最佳水平。将不同包装膜包装的草鱼置于4℃下贮藏11 d,结果表明,与纯PE包装膜相比,添加BW-SiO_(2)功效因子的复合PE包装膜对草鱼的保鲜效果更好,能够减缓鱼肉的水分流失和脂质氧化反应,有效延缓鱼肉的腐败变质进程,从而延长鱼肉的贮藏期。结论PE-BW-SiO_(2)复合包装膜具有良好的理化性能和保鲜效果,它有效地阻隔了外界水分的渗透和氧气的进入,从而减缓了水分流失和脂质氧化反应,同时还能防止微生物的滋长。此包装膜有效延缓了草鱼的腐败变质进程,在4℃下贮藏时将草鱼的货架期延长至11 d。 展开更多
关键词 草鱼 保鲜 蜂蜡 纳米SiO_(2) PE-bw-SiO_(2)复合包装膜
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Comparative study of the effects of Tartary buckwheat seed and sprout consumption on the physiological indices and gut microbiota of C57BL/6J mice
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作者 Guohui Nan Haixia Zhao +6 位作者 Qiong Wu Lisong Liu Zichao Guan Chenglei Li Huala Wu Dabing Xiang Qi Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期791-800,共10页
Tartary buckwheat(Fagopyrum tataricum)is a well-known pseudocereal for its health and economic value.However,abundant antinutritional factors(ANFs)reduces its health benefits.As reported,germination can improve the nu... Tartary buckwheat(Fagopyrum tataricum)is a well-known pseudocereal for its health and economic value.However,abundant antinutritional factors(ANFs)reduces its health benefits.As reported,germination can improve the nutritional profile of grains.In this study,we systematically evaluate the safety of Tartary buckwheat seeds(TB)and Tartary buckwheat sprouts(TBS)used as high active ingredients.After evaluating nutrition levels,bioactive compounds and ANFs in TBS during germinating,5^(th)-day TBS were selected as the raw material.C57BL/6J mice were gavaged daily with distilled water,TB,or TBS for 6 weeks.The physiological indices related to ANFs were determined.Results showed that the TB intake tends to generate negative effects on the gut microbiota,and organs.Additionally,upon TB intake,the Fe^(3+)content in serum,trypsin activity in pancreas and jejunum decreased,while the cytokine,IgE,and histamine levels in serum,water content in faeces,cytokine levels in liver and jejunum increased.Conversely,TBS did not induce any obvious negative effects on the above relevant indices and showed better lipid-lowering effect.Altogether,TBS are safer and more effective as a raw material to produce the functional food for long-term consumption with the intention of preventing and treating hyperlipidaemia. 展开更多
关键词 Tartary buckwheat Tartary buckwheat sprouts Antinutritional factors Gut microbiota Health effect
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Preparation of Tartary Buckwheat Seed Coating Agent and Its Effect on Germination
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作者 Xin Zou Jieyu Zhang +6 位作者 Ting Cheng Yangyang Guo Xiao Han Han Liu Yuxing Qin Jie Li Dabing Xiang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期699-712,共14页
To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design ... To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design methodsto investigate the seed coating formula and physical properties of Tartary buckwheat. The specific effects ofeach component on Tartary buckwheat seed germination are analyzed. The findings reveal that the seed coatingagent formulated with 1.5% polyvinyl alcohol, 0.15% sodium alginate, 0.2% op-10, 0.1% polyacrylamide, 8% colorant,3% ammonium sulfate, 1% potassium dihydrogen phosphate, and 0.15% carbendazim exhibits the mosteffective coating. It demonstrates optimal physical properties and promotes seed germination efficiently. The suspensionrate of this seed coating agent reaches 91.12%, with a mere 2.13% coating shedding rate and 2.5% coatingseed rot rate. Furthermore, it achieves a germination percentage of 99.17%, which is 20.84% higher than the lowestgroup. The germination potential and index are also significantly higher than the lowest group, with anincrease of 20.84% and 26.56%, respectively. Additionally, the vitality index is 553.08, a 15.75% increase comparedto the lowest group. The application of seed coating agents helps reduce seed resource loss, increase plant numbers,and ultimately enhance agricultural yields. This finding holds practical significance in agriculturalproduction. 展开更多
关键词 Tartary buckwheat seed coating agent FORMULA GERMINATION
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Silicon Mitigates Aluminum Toxicity of Tartary Buckwheat by Regulating Antioxidant Systems
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作者 Anyin Qi Xiaonan Yan +10 位作者 Yuqing Liu Qingchen Zeng Hang Yuan Huange Huang Chenggang Liang Dabing Xiang Liang Zou Lianxin Peng Gang Zhao Jingwei Huang Yan Wan 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第1期1-13,共13页
Aluminum (Al) toxicity is a considerable factor limiting crop yield and biomass in acidic soil. Tartary buckwheatgrowing in acidic soil may suffer from Al poisoning. Here, we investigated the influence of Al stress on... Aluminum (Al) toxicity is a considerable factor limiting crop yield and biomass in acidic soil. Tartary buckwheatgrowing in acidic soil may suffer from Al poisoning. Here, we investigated the influence of Al stress on the growthof tartary buckwheat seedling roots, and the alleviation of Al stress by silicon (Si), as has been demonstrated inmany crops. Under Al stress, root growth (total root length, primary root length, root tips, root surface area, androot volume) was significantly inhibited, and Al and malondialdehyde (MDA) accumulated in the root tips. At thesame time, catalase (CAT) and ascorbate peroxidase activities, polyphenols, flavonoids, and 1,1-diphenyl-2-picrylhydrazyl(DPPH) and 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) free-radical scavenging abilitywere significantly decreased. After the application of Si, root growth, Al accumulation, and oxidative damage wereimproved. Compared to Al-treated seedlings, the contents of ·O2− and MDA decreased by 29.39% and 25.22%,respectively. This was associated with Si-induced increases in peroxidase and CAT enzyme activity, flavonoidcompounds, and free-radical scavenging (DPPH and ABTS). The application of Si therefore has positive effectson Al toxicity in tartary buckwheat roots by reducing Al accumulation in the roots and maintaining oxidationhomeostasis. 展开更多
关键词 Tartary buckwheat aluminum stress SILICON root growth oxidative stress
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SMA490BW耐候钢焊接与焊后热处理残余应力的数值模拟
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作者 户迎灿 王秋影 +2 位作者 邱培现 许骏 廖子文 《电焊机》 2024年第2期77-82,共6页
SMA490BW耐候钢焊接过程中会产生较大的残余应力,常使用去应力退火的热处理方式消除残余应力。建立了SMA490BW耐候钢的焊接过程和焊后热处理过程中的有限元模型,对焊接以及焊后热处理的残余应力场进行了有限元模拟和验证。通过引入材料... SMA490BW耐候钢焊接过程中会产生较大的残余应力,常使用去应力退火的热处理方式消除残余应力。建立了SMA490BW耐候钢的焊接过程和焊后热处理过程中的有限元模型,对焊接以及焊后热处理的残余应力场进行了有限元模拟和验证。通过引入材料的CREEP本构模型,利用Norton-Bailey指数方程模拟计算了焊后热处理时材料的蠕变行为,得到热处理对的焊接残余应力的影响。研究结果表明:使用CREEP本构模型,引入材料的蠕变行为可以较好地模拟焊接工件的焊后热处理过程中的应力应变变化,计算得到的残余应力值与实测值有较好的一致性。这为工业上优化SMA490BW耐候钢的焊接工艺、降低残余应力提供了理论支持。 展开更多
关键词 SMA490bw耐候钢 热处理 残余应力 数值模拟
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SMA490BW耐候钢TIG焊接接头残余应力分析
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作者 马龙 《焊接》 2024年第6期68-73,80,共7页
【目的】旨在进行SMA490BW耐候钢TIG焊接接头疲劳寿命的评估。【方法】采用盲孔法、X射线法、有限元分析3种方法对SMA490BW耐候钢TIG焊接接头进行了焊接残余应力分析,并对切割小试样引起的残余应力变化进行分析。【结果】结果表明,SMA49... 【目的】旨在进行SMA490BW耐候钢TIG焊接接头疲劳寿命的评估。【方法】采用盲孔法、X射线法、有限元分析3种方法对SMA490BW耐候钢TIG焊接接头进行了焊接残余应力分析,并对切割小试样引起的残余应力变化进行分析。【结果】结果表明,SMA490BW耐候钢纵向残余应力在焊缝拉应力峰值接近材料屈服强度,远离焊缝中心残余应力迅速降低并进一步转变为压应力,此分布规律为典型的纵向残余应力分布特征。在整体试板上采用线切割出用于疲劳试验的足尺寸小试样,小试样上纵向残余应力的峰值接近230 MPa,约为屈服强度的70%,纵向残余应力在横向分布规律保持不变。【结论】该部分所建立的有限元模型分析结果与测试数据吻合很好,证实模型的热源模型、力学边界条件均与实际工艺接近,采用该计算模型的精度和正确性可以保障。 展开更多
关键词 SMA490bw耐候钢 残余应力 盲孔法 有限元法 X射线法
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Determination of total flavonoids content in buckwheat and inhibition of α-amylase activity
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作者 Huijing Chao Rong Yang +2 位作者 Ming Yang Beijie Xu Xu Zhao 《Journal of Polyphenols》 2024年第3期98-105,共8页
Diabetes is one of the most difficult chronic diseases to cure in the world,which seriously affects people’s health and quality of life.Flavonoids in buckwheat can regulate blood glucose levels by inhibitingα-amylas... Diabetes is one of the most difficult chronic diseases to cure in the world,which seriously affects people’s health and quality of life.Flavonoids in buckwheat can regulate blood glucose levels by inhibitingα-amylase activity.Therefore,sweet buckwheat produced in Inner Mongolia was used as the research object,and buckwheat fl avonoids were extracted by ultrasonic-assisted extraction method.Total fl avonoids content was determined by ultraviolet-visible spectrophotometry.With acarbose as the positive control,the inhibition test ofα-amylase was carried out by DNS colorimetry to study the inhibition behavior of fl avonoids onα-amylase activity.The results showed that the extraction process of flavonoids was stable and reliable,and the established method for the determination of flavonoids was simple,accurate and reproducible.The total flavonoids content of buckwheat samples was 2.706 mg/g,buckwheat total fl avonoids extraction solution had an inhibitory eff ect onα-amylase,and its median inhibition concentration(IC_(50))was 38.53 mg/mL.The results of this experiment provide a technical reference for the development and utilization of fl avonoids in Inner Mongolia sweet buckwheat,and provide a theoretical reference for the development and application of flavonoid-rich hypoglycemic food. 展开更多
关键词 buckwheat total flavonoids content Α-AMYLASE activity inhibition
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修正BW方法在中国大气降水δ^(18)O空间分布研究中的应用 被引量:6
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作者 杨俊华 秦翔 +3 位作者 吴锦奎 段克勤 杜文涛 刘焕才 《冰川冻土》 CSCD 北大核心 2014年第6期1430-1439,共10页
为研究中国大气降水δ18O的空间分布,利用81个大气降水和冰芯站点δ18O资料和BW回归模型,拟合出大气降水δ18O与纬度和海拔的定量关系:δ18O=-0.024LAT2+1.541LAT-0.002 ALT-29.678.同时,为了优化BW回归模型的拟合结果,对BW回归模型的... 为研究中国大气降水δ18O的空间分布,利用81个大气降水和冰芯站点δ18O资料和BW回归模型,拟合出大气降水δ18O与纬度和海拔的定量关系:δ18O=-0.024LAT2+1.541LAT-0.002 ALT-29.678.同时,为了优化BW回归模型的拟合结果,对BW回归模型的残差做了内插并比较了不同插值方法的精度.结果表明:以降水量为辅助变量的协同克里格法对残差的预测效果最好,与广泛采用的反距离加权法相比,该方法预测的BW残差与实际残差间的RMSE减小了0.14‰,ME也更接近于0.最后,利用最优的插值方法生成了BW回归模型的残差分布图,并将其与BW的模拟结果叠加得到了中国降水δ18O的空间分布图.其结果总体上反映了中国大气降水中δ18O的分布状况,为降水δ18O的现代过程研究以及古气候和古水文的研究提供了资料参考. 展开更多
关键词 降水δ^18O 中国 空间插值方法 bw方法 优化
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RAPD Analysis for Genetic Diversity of Nineteen Common and Tartary Buckwheat Varieties 被引量:9
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作者 邓琳琼 张奎 +1 位作者 黄凯丰 陈庆富 《Agricultural Science & Technology》 CAS 2011年第1期65-69,共5页
[Objective]The study aimed to carry out RAPD analysis of genetic diversity of common and tartary buckwheat varieties.[Method] The genetic diversity of 19 common and tartary buckwheat varieties including the tested var... [Objective]The study aimed to carry out RAPD analysis of genetic diversity of common and tartary buckwheat varieties.[Method] The genetic diversity of 19 common and tartary buckwheat varieties including the tested varieties in Guizhou region during 1999-2010 and their parents were studied using 7 primers by means of random amplified polymorphic DNA(RAPD).[Result]A total of 149 DNA bands were obtained.In which,141 bands were polymorphic,accounting for 94.89%.Polymorphism analysis and cluster analysis showed that all varieties had their own special bands different from each other.The varieties native to Weining were close to each other,and other common buckwheat varieties were obviously different from each other.The interspecific genetic variation was the greatest;the intraspecific genetic variation of common buckwheat varieties was greater than that of tartary buckwheat varieties.[Conclusion]The RAPD fingerprints of the 19 buckwheat varieties were established in present study. 展开更多
关键词 Common buckwheat Tartary buckwheat RAPD Genetic diversity
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基于BW算法的高采样率心电数据无损压缩 被引量:4
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作者 田峰 饶妮妮 +1 位作者 程煜 徐尚蕾 《生物医学工程学杂志》 CAS CSCD 北大核心 2008年第4期790-794,共5页
目前对心电数据压缩的研究主要集中在对低采样率心电数据的压缩,我们提出了一种基于BW(Bur-rows-Wheeler)算法对高采样率心电数据的无损压缩算法。首先对原始心电数据进行差分变换,将部分16位二进制差值表示为8位,然后对差分结果进行前... 目前对心电数据压缩的研究主要集中在对低采样率心电数据的压缩,我们提出了一种基于BW(Bur-rows-Wheeler)算法对高采样率心电数据的无损压缩算法。首先对原始心电数据进行差分变换,将部分16位二进制差值表示为8位,然后对差分结果进行前移编码,使得相同字符集中于某一段区域,最后通过算术编码得到高压缩比。结果表明,该算法不仅适用于高采样率体表心电数据的压缩,而且也适用于心内心电数据的压缩,平均压缩比分别达到3.547和3.608。同现有的心电无损压缩算法相比,它在压缩效果上获得了较大改进。另外针对高采样率心电数据,使用该算法进行无损压缩也可以得到较好的压缩效果。 展开更多
关键词 bw算法 心电数据 高采样率 无损压缩
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BW模型在掩护水域内波浪计算中的应用 被引量:6
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作者 冯卫兵 黄莹娜 厉佳卉 《水运工程》 北大核心 2015年第11期8-13,共6页
采用MIKE21-BW模型分别对平底地形下单突堤的波浪绕射以及实际地形下某港港内波浪场进行模拟及验证,将模拟结果与规范中的计算图解及物模试验结果进行对比分析,吻合良好。同时研究发现,由于该模型数值格式的限制,在波浪斜向入射的情况下... 采用MIKE21-BW模型分别对平底地形下单突堤的波浪绕射以及实际地形下某港港内波浪场进行模拟及验证,将模拟结果与规范中的计算图解及物模试验结果进行对比分析,吻合良好。同时研究发现,由于该模型数值格式的限制,在波浪斜向入射的情况下,模型的计算结果存在较为明显的误差,而经过地形逆向旋转处理,将波浪入射方向调整为正向入射的方法可以较好地改善模型的计算结果。另外,在某港实际地形下的波浪模拟中,还探讨了谱峰因子γ的变化对该港港内波浪场的影响。 展开更多
关键词 波浪 掩护水域 数值模拟 bw模型
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高速列车转向架SMA490BW耐候钢焊接接头低温性能研究 被引量:14
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作者 吴向阳 张志毅 +1 位作者 刘拥军 王银灵 《热加工工艺》 CSCD 北大核心 2015年第19期29-31,35,共4页
转向架作为高速列车车走行部的主要构件,在工作过程中承受着交变载荷的作用。SMA490BW耐候钢因具有较高的强度、韧性及良好的耐大气腐蚀性,专门用作CRH2型高速动车组转向架焊接构架关键材料。在低温条件下的SMA490BW耐候钢接头性能优劣... 转向架作为高速列车车走行部的主要构件,在工作过程中承受着交变载荷的作用。SMA490BW耐候钢因具有较高的强度、韧性及良好的耐大气腐蚀性,专门用作CRH2型高速动车组转向架焊接构架关键材料。在低温条件下的SMA490BW耐候钢接头性能优劣直接关系着高速列车车体的运行安全。主要针对该材料对接接头,进行了不同低温环境下接头的拉伸试验、冲击试验、疲劳强度试验,研究抗拉强度、冲击值随温度变化规律。试验结果表明:随着温度的降低,接头的抗拉强度略有提高,但韧性降低,疲劳性能因缺陷存在而变化不大。 展开更多
关键词 SM490bw 低温条件 焊接接头 力学性能
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SMA490BW钢双丝焊接头组织及力学性能研究 被引量:9
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作者 孙中文 吴向阳 +3 位作者 张志毅 何永攀 李远星 陈辉 《热加工工艺》 CSCD 北大核心 2016年第11期55-58,共4页
对SMA490BW钢进行双丝MAG焊接,并研究了接头组织及力学性能。结果表明,SMA490BW钢双丝焊焊缝成型美观,无未熔合、夹渣等焊接缺陷。焊缝各层组织有差异,上层组织主要为先共析铁素体、针状铁素体、条状铁素体和粒状贝氏体组织;中层柱状晶... 对SMA490BW钢进行双丝MAG焊接,并研究了接头组织及力学性能。结果表明,SMA490BW钢双丝焊焊缝成型美观,无未熔合、夹渣等焊接缺陷。焊缝各层组织有差异,上层组织主要为先共析铁素体、针状铁素体、条状铁素体和粒状贝氏体组织;中层柱状晶组织有细化趋势;底层出现过热的魏氏组织。接头硬度和抗拉强度满足生产要求,焊接残余应力较小,接头疲劳性能优良,疲劳极限可达到420 MPa。 展开更多
关键词 SMA490bw 双丝MAG焊 组织 力学性能
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SWAN模型与BW模型在舟山泗礁换流站设计波浪计算中的联合应用 被引量:2
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作者 邵杰 胡列翔 +1 位作者 杨雷霞 穆锦斌 《水运工程》 北大核心 2015年第10期13-19,共7页
选取浙江北部嵊泗海域作为研究对象,以大、小网格嵌套的SWAN模型在龙口前沿的波要素计算结果作为BW模型的边界条件,在两个模型的联合应用下模拟了舟山泗礁换流站掩护区外和掩护区内的波浪场分布。结果表明,外海E、ESE、SE向来波传至马... 选取浙江北部嵊泗海域作为研究对象,以大、小网格嵌套的SWAN模型在龙口前沿的波要素计算结果作为BW模型的边界条件,在两个模型的联合应用下模拟了舟山泗礁换流站掩护区外和掩护区内的波浪场分布。结果表明,外海E、ESE、SE向来波传至马关围堤前沿海域时波向已偏转成SSE向,其中ESE向来波下龙口前沿的波高最大,进入掩护区后绕射波的衰减较为明显,将绕射波与局地风浪叠加,得到了泗礁换流站100 a一遇、50 a一遇的设计波要素,其有效波高分别为1.08、0.98 m。SWAN模型与BW模型的联合应用,使得掩护区内外大跨度地形下的波浪折射、绕射、反射等现象均得到了高精度的模拟,在舟山泗礁换流站设计波浪计算中具有良好的适应性。 展开更多
关键词 SWAN模型 bw模型 换流站 波浪计算 联合应用
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Variation of Glucose Content in Tartary Buckwheat Seeds 被引量:4
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作者 时政 宋毓雪 +1 位作者 韩承华 黄凯丰 《Agricultural Science & Technology》 CAS 2011年第2期214-216,共3页
[Objective] This study aimed to finding out the difference in glucose content of tartary buckwheat seeds from different origins.[Method] Taking 35 kinds of tartary buckwheat from different origins as the test material... [Objective] This study aimed to finding out the difference in glucose content of tartary buckwheat seeds from different origins.[Method] Taking 35 kinds of tartary buckwheat from different origins as the test materials,the glucose content of seeds had been determined.[Result] The variation range of glucose content in 35 kinds of tartary buckwheat was from 0.055 6% to 0.840 2% with an average of 0.321 7%.There was a difference in glucose content of tartary buckwheat from different origins.The seeds T324 from Weining in Guizhou had the highest glucose content,while the seeds T398 also from Weining in Guizhou had the lowest glucose content.[Conclusion] This study provides a reference for the genetic variation law of glucose content in different tartary buckwheat resources. 展开更多
关键词 Tartary buckwheat Glucose content Genetic variation
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Variation of Protein Content in Tartary Buckwheat Seeds 被引量:4
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作者 黄凯丰 时政 +2 位作者 韩承华 赵祖贵 何平贵 《Agricultural Science & Technology》 CAS 2011年第1期99-101,共3页
[Objective]The aim was to select tartary buckwheat materials with high protein content.[Method]Used 35 kinds of tartary buckwheat as experimental material,and the protein content of seeds had been determined.[Result]T... [Objective]The aim was to select tartary buckwheat materials with high protein content.[Method]Used 35 kinds of tartary buckwheat as experimental material,and the protein content of seeds had been determined.[Result]The protein content of 35 kinds of tartary buckwheat will change in the range of 23.65-193.28 mg/g with an average of 111.85 mg/g.There was difference among different origins of tartary buckwheat.The seeds from Hezhang in Guizhou and Sichuan had highest protein content,while the seeds from Nayong had lowest protein content.[Conclusion]The study had provided theoretical basis for the further study on the genetic and variation law of protein content in different tartary buckwheat resources. 展开更多
关键词 Tartary buckwheat Protein content Genetic variation
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Research on Variation in Sucrose Content among Different Tartary Buckwheat Genotypes 被引量:3
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作者 黄凯丰 时政 +2 位作者 宋毓雪 韩承华 陈庆富 《Agricultural Science & Technology》 CAS 2011年第2期211-213,共3页
[Objective] The aim was to determine the difference in sucrose content of different tartary buckwheat sources,so as to screen low-sucrose buckwheat materials.[Method] The sucrose contents of 35 tartary buckwheat mater... [Objective] The aim was to determine the difference in sucrose content of different tartary buckwheat sources,so as to screen low-sucrose buckwheat materials.[Method] The sucrose contents of 35 tartary buckwheat materials from different regions were measured.[Result] The sucrose content of the 35 tartary buckwheat materials varied from 0.007 7% to 0.208 9% with an average of 0.051 8%.There was some difference among the tartary buckwheat materials from different regions.The seeds from Hezhang in Guizhou had higher sucrose content,while the seeds from Nayong in Guizhou had lower sucrose content.[Conclusion] The content of sucrose was significantly low in tartary buckwheat,which could be popularized as a kind of low-sugar crop. 展开更多
关键词 Tartary buckwheat Sucrose content VARIATION
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