对《中图法》(第四版)类目注释的系统认识     

杨衡 《农业图书情报学刊》2005,17(3):154-157

本文从语言特点、编排体例及内容特点出发,对《中图法》(第四版)类目注释进行了系统的认识,并就此提出了自己的一些看法。  相似文献   

智能喷水灭火装置不同布置方式技术分析   总被引：1，自引：0，他引：1  

王相宇 《湖南农机》2011,38(3):33-34

在考虑喷水强度和喷水均匀性的基础上,文章针对智能喷水灭火装置的特性并综合国内一些工程实践经验,对智能喷水灭火装置的主要几种布置形式做出了技术分析比较,指出对于狭长型建筑物应采取单排布置形式,在多行列布置时宜被首选应用.  相似文献   

中国古典园林与戏曲舞台空间布景的共通性     

樊路遥 《安徽农业科学》2016,(13)

优秀的传统文化是一个民族劳动人民智慧的结晶。随着全球经济一体化的发展，中国传统文化受到西方文化的猛烈冲击，因此以中国古典园林和戏曲艺术的研究为代表的优秀传统文化的研究对中国现代文化发展有着深远意义。笔者通过查阅国内现有的关于古典园林和戏曲舞台空间布景的研究，发现该领域的研究并不丰富。通过对二者空间布局的层次、置陈布势的常用手法和艺术性进行共通性研究，希望对古典园林和戏曲保护提供参考和指导。  相似文献   

Selecting fish‐based metrics responding to human pressures in French natural lakes and reservoirs: towards the development of a fish‐based index (FBI) for French lakes     

L. Launois  J. Veslot  P. Irz  C. Argillier 《Ecology of Freshwater Fish》2011,20(1):120-132

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Effects of arrangement of surge-rootirrigation emitters on growth,yield andwater use efficiency of apple trees     

LI Zhongjie  FEI Liangjun  HAO Kun  LIU Teng  CHEN Nanshu  ZHANG Quanju  HUANG Deliang 《排灌机械工程学报》2020,38(7):713-719

Six-year old apple trees were selected for field experiment. The objective of this study was to obtain the reasonable arrangement of surge-root irrigation emitters in apple orchards. There were three factors: the buried depth H( 25,40,55 cm),the horizontal distance L( 30,40,60 cm) between the emitters and the trunk of the experimental tree,and the number of the irrigation emitters N( 1,2,4). The effect of the arrangement of surge-root irrigation emitters on the growth,yield and irrigation water use efficiency( IWUE) of apple trees were studied in Northern Shaanxi where the irrigation quota takes 60%-75% of the field water capacity. The results showed that the arrangement of emitters for surge-root irrigation had a significant effect on apple tree yield and IWUE,especially,the yield and IWUE reached 28 388. 17 kg/hm2 and 16. 83 kg/m3 in treatment T3,respectively. At the same L and N levels( T1,T2,and T3),the yield and IWUE in treatment T3 were the highest,and the yields in treatments T1 and T2 were decreased by 26.22% and 31.48%,while IWUE is reduced by14.02% and 18.12% compared with T3,respectively. At the same H and N levels( T3,T4,and T5),the yield and IWUE of apple trees were decreased with increasing L level. Especially,when L was 30 cm( T3),the yield and IWUE were the highest. The same L and H levels( T3,T6,and T7) could promote the growth of apple trees when N was 2( T3). Compared with treatment T3,it was found that the increment of new shoots was decreased by 8.07%-18.71%,and the fruit diameter was decreased by 5.41%-9.11%. Therefore,two emitters should be arranged symmetrically on both sides of an apple tree,each was buried at a 40 cm depth and 30 cm away from the trunk of the tree to effectively improve the yield and IWUE of the apple tree in mountainous areas in Northern Shaanxi.  相似文献   

刀具布置对茎秆切碎还田机振动的影响分析   总被引：7，自引：0，他引：7  

姬江涛  李庆军  蔡苇 《农机化研究》2003,(4):63-64

分析了影响茎秆切碎还田机振动的主要因素，并对典型机具的刀片排列方案进行了研究．从而提出了茎秆切碎还田机刀片排列的主要理论依据。  相似文献   

Transient heat transfer characteristics of air-array-jet impingement with different nozzle arrangements on high-temperature flat plate in small jet-to-plate distance     

LI Meixiang  ZHU Keqian  XIE Yu  CAI Tingting  YUAN Ningyi  DING Jianning 《排灌机械工程学报》2020,38(3):277-284

Numerical studies on transient heat transfer characteristics of air-array-jet impingement with a small jet-to-plate distance and a large temperature difference between nozzles and plate were presented.The dimensionless jet-to-plate distance(H/D)was 0.2,and non-dimensional nozzle-to-nozzle spacing(S/D)was 3,4,5 and 6,respectively.It is found that the quenching time is shortened at a constant total mass flow at air jet inlet m·(m·=218.21 kg/h),and the heat transfer uniformity is deterio-rated as S/D increases.However,the adding reversed-flow nozzles can shorten the quenching time of the glass plate considerably with a modest change in the heat transfer uniformity.The results at variable m·are the same as those at a fixed m·.Furthermore,the parity and arrangement of nozzles are also discussed,It is found that an odd number of nozzles is more beneficial for transient heat transfer.Based on these results,an appropriate proposal for ultra-thin glass tempering process is presented.  相似文献   

基质深度及基质袋摆放方式对春季袋培番茄产量、品质和养分吸收的影响   总被引：1，自引：1，他引：0  

张佼  屈锋  杨甲甲  胡晓辉 《中国农业大学学报》2020,25(8):43-53

为探究不同栽培深度基质和基质袋摆放对春季袋培番茄产量、品质、养分吸收和基质养分利用率的影响,以‘巴宝丽’番茄为试材,设置不同基质深度(7.5、10.5和13.5cm)及基质袋不同摆放方式(地面摆放和地面下沉20cm),共6个处理,测定了番茄的生长发育、产量、品质和养分吸收等指标。结果表明:栽培基质深度对产量、果实品质均有显著影响;基质袋摆放方式对产量影响不显著,但显著影响果实可溶性蛋白、番茄红素、硝酸盐和有机酸含量;基质深度和基质袋摆放方式对果实硝酸盐含量的影响有显著的交互作用。随着栽培基质深度的增加,产量显著提高,品质明显改善;基质深度13.5cm时,番茄单株产量最高,达3.83kg/株。基质袋摆放方式和基质深度对番茄开花期、初果期及盛果期P和K的累积吸收影响显著,基质深度对番茄开花期、初果期和盛果期N的吸收也有显著影响,基质深度和基质袋摆放方式对开花期和初果期番茄植株N、P和K的累积吸收存在显著的交互作用。基质内N、P和K养分利用率均是基质深度为13.5cm的处理最高,且不同基质袋摆放方式对基质养分利用率无显著影响。综上,为实现省工省力且高产优质载培,在实际生产中推荐将春季栽培番茄的基质深度设置为13.5cm(即基质供应量为9L/株)且地面摆放。  相似文献   

叶片布置方式对双吸离心泵径向力的影响     

赵万勇  陈帅  赵强  马得东  梁允昇  彭虎廷 《排灌机械工程学报》2021,39(4):331-337

为研究叶片布置方式对双吸离心泵径向力的影响,在其他外部因素不变的情况下,对3种叶片布置方案的离心泵进行非定常模拟计算,结果表明:较对称布置方案,采用交错30°布置的叶片能够有效提高离心泵的扬程,采用交错15°布置的叶片对离心泵扬程具有消极影响.同时,采用交错布置方案会导致离心泵的效率下降;在设计工况下,与对称布置方案相比,叶片采用交错布置能够有效降低离心泵内的压力脉动水平,且交错角度越大,压力脉动水平降低的越明显.叶片采用交错布置能够有效降低作用在叶轮上的稳态径向力的大小,其中采用交错30°布置方案在1.1Q_d工况下稳态径向力相对降低42.284%.最后,叶片采用交错30°布置对改善叶轮所受瞬态径向力的脉动特性与幅值大小的效果最为明显.  相似文献   

湖南教育报刊社新址景观环境设计   总被引：1，自引：1，他引：0  

徐斌  陈琼琳  龙岳林 《湖南农业大学学报(自然科学版)》2007,33(1):40-43

本着对资源的保护与利用、历史文化的延续和景观再生的设计指导思想,针对湖南教育报刊社的发展历史和其新址的自然条件与景观特色,以尊重自然、传承历史文化、创造“天人合一”的人居环境为设计理念,对湖南教育报刊社新址景观环境设计的设计目标和主要设计内容进行了阐述.  相似文献