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翼身结合框结构仿生设计 被引量:13
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作者 岑海堂 陈五一 +1 位作者 喻懋林 刘雪林 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2005年第1期13-16,共4页
相似是仿生的基础 ,全面系统地理解工程原型的功能需求和生物体各个层次的优异结构 ,准确把握生物体与工程原型的相似性 ,是结构仿生设计的关键 .为减轻翼身结合框重量 ,分析了竹干与翼身结合框相似的承力性能 ,借鉴竹干的细观结构形状... 相似是仿生的基础 ,全面系统地理解工程原型的功能需求和生物体各个层次的优异结构 ,准确把握生物体与工程原型的相似性 ,是结构仿生设计的关键 .为减轻翼身结合框重量 ,分析了竹干与翼身结合框相似的承力性能 ,借鉴竹干的细观结构形状和排列方式 ,应用结构仿生原理设计了仿生翼身结合框 .有限元分析结果表明 ,在保证结合框强度、刚度的前提下 ,仿生结构与原型相比重量可减轻 2 .1 % . 展开更多
关键词 减重 仿生设计 翼身结合框 竹干
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湖南发现奇特变异毛竹
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《世界竹藤通讯》 2005年第1期50-50,共1页
竹干一节青绿,另一节却为金黄,或一节中青绿与金黄相间,呈对称分布,这样的毛竹变异种近日在湖南双牌县阳明山国家森林公园被发现。据介绍,毛竹是禾本科竹亚纲竹属植物,通常竹干为青绿色。以前,曾在广西和江西发现毛竹变异种,均... 竹干一节青绿,另一节却为金黄,或一节中青绿与金黄相间,呈对称分布,这样的毛竹变异种近日在湖南双牌县阳明山国家森林公园被发现。据介绍,毛竹是禾本科竹亚纲竹属植物,通常竹干为青绿色。以前,曾在广西和江西发现毛竹变异种,均为通体金黄色,或呈不规则分布,被称为“花间毛竹”或“黄金间碧玉”,具有很高的观赏价值。 展开更多
关键词 湖南 变异毛竹 青绿色 竹干 观赏价值
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Effect of the Interference Instant of Zeolite HY Catalyst on the Pyrolysis of Pubescens 被引量:3
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作者 刘文武 胡常伟 +2 位作者 杨宇 祝良芳 重冬梅 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期351-354,共4页
A laboratory reactor was designed to test the effect of the interference instant of HY on the pyrolysis of pubescens.The time instant for intermediate species from pyrolysis to contact HY was controlled by varying the... A laboratory reactor was designed to test the effect of the interference instant of HY on the pyrolysis of pubescens.The time instant for intermediate species from pyrolysis to contact HY was controlled by varying the position of the catalyst bed relative to the pyrolytic cell.It was found that the effect of the interference instant was significant on the variation of different intermediate species,and the yield and quality of the products.The results also showed that,with the increase in the distance between the pyrolytic cell and the catalyst bed,the yield of liquid and relative content of the organics such as aldehyde,phenols,etc.,decreased,while the yield of residue and relative content of acetic acid increased.The deoxygenation of the intermediate species was favored when the catalyst exerted its performance on them immediately after their formation. 展开更多
关键词 zeolite HY catalytic pyrolysis pubescens acetic acid intermediate conversion
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Growth and Phosphorus Uptake of Oat (Avena nuda L.) as Affected by Mineral Nitrogen Forms Supplied in Hydroponics and Soil Culture 被引量:3
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作者 FAN Ming-Shou LI Zhen +1 位作者 WANG Feng-Mei ZHANG Jian-Hua 《Pedosphere》 SCIE CAS CSCD 2009年第3期323-330,共8页
Plants show different growth responses to N sources supplied with either NH4^+ or NO3^-. The uptake of different N sources also affects the rhizosphere pH and therefore the bioavallability of soil phosphorus, particu... Plants show different growth responses to N sources supplied with either NH4^+ or NO3^-. The uptake of different N sources also affects the rhizosphere pH and therefore the bioavallability of soil phosphorus, particularly in alkaline soils. The plant growth, P uptake, and P availability in the rhizosphere of oat (Arena nuda L.) grown in hydroponics and in soil culture were investigated under supply with sole NH4^+-N, sole NO3-N, or a combination. Sole NO^- -fed oat plants accumulated more biomass than sole NH4^+ -fed ones. The highest biomass accumulation was observed when N was supplied with both NH^+ -N and NO3^- -N. Growth of the plant root increased with the proportion of NO3^- in the cultural medium. Better root growth and higher root/shoot ratio were consistently observed in NO3^- fed plants. However, root vigor was the highest when N was supplied with NO3^- +NH4^+. NH4^+ supply reduced the rhizosphere pH but did not affect P uptake by plants grown in soils with CaHPO4 added as P source. No P deficiency was observed, and plant P concentrations were generally above 2 g kg^-1. P uptake was increased when N was supplied partly or solely as NO3^--N, similarly as biomass accumulation. The results suggested that oat was an NO3-preferring plant, and NO3^- -N was essential for plant growth and the maintenance of root absorption capacity. N supply with NH4^+ -N did not improve P nutrition, which was most likely due to the absence of P deficiency. 展开更多
关键词 alkaline soils nitrogen nutrition oat (Arena nuda L.) P uptake rhizosphere pH
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Efficacy of electroacupuncture for patients with dry eye syndromes:a randomized controlled trial 被引量:3
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作者 ZHANG Dan ZHAO Yan +6 位作者 YANG Yanting LIU Xiaoxu ZHAO Yue SHI Zheng HONG Jue LIU Jie MA Xiaopeng 《Journal of Acupuncture and Tuina Science》 CSCD 2022年第6期489-498,共10页
Objective To observe the efficacy of electroacupuncture(EA)in treating dry eye syndromes(DES)and its regulatory effects on patient’s quality of life(QOL),anxiety,and depression.MethodsBy following a randomized contro... Objective To observe the efficacy of electroacupuncture(EA)in treating dry eye syndromes(DES)and its regulatory effects on patient’s quality of life(QOL),anxiety,and depression.MethodsBy following a randomized controlled study design,eligible DES patients were allocated to an EA group(EAG)or an acupuncture group(AG).Patients in the AG were intervened by acupuncture alone,while in the EAG,electrical stimulation was applied to Cuanzhu(BL2)and Taiyang(EX-HN5)in addition to the same treatment in the AG.Changes in clinical manifestations,ocular surface disease index(OSDI),Schirmer tear test-1(STT-1),tear-film break-up time(TF-BUT),cornea fluorescein staining(CFS),and corneal sensitivity(CS)were observed,as well as changes in the short-form 36-item health survey(SF-36)and hospital anxiety and depression scale(HADS)scores.ResultsThe scores of clinical symptoms,OSDI,and CFS decreased significantly in both EAG and AG when compared with the baseline values(P<0.05),respectively,while the TF-BUT and CS increased significantly(P<0.05),and the tear secretion of patients in the EAG increased(P<0.05).Compared with those before treatment,the scores of physical role functioning,general health perception,emotional role functioning,and mental health of patients in both EAG and AG showed significant increases after treatment(P<0.05),together with a marked decrease in the score of anxiety(P<0.05).Compared with the AG,the EAG obtained a more significant increase in STT-1(P<0.05).ConclusionDES patients respond well to both EA and acupuncture treatments,manifested by prolonged TF-BUT and improvement of CS.Meanwhile,the two approaches can improve QOL and reduce anxiety.Furthermore,EA appears more effective in increasing tear secretion than acupuncture alone. 展开更多
关键词 Acupuncture Therapy ELECTROACUPUNCTURE Point Cuanzhu(BL2) Point Taiyang(EX-HN5) Dry Eye Syndromes Quality of Life Emotional Regulation Randomized Controlled Trial
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