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21.
为了探析引起地温空调井抽回灌效果的主要制约因素,通过单相关系数分析、主成分绝对得分的源解析模型、拟合度检验和多元线性回归的方法分析影响单井回灌效率的影响因素。结果表明:井径、滤水管孔隙率及抽回灌井数比与单井回灌效率的相关性和拟合度较好,故将井径、滤水管孔隙率及抽回灌井数比作为影响单井回灌效率的关键因子,同时分析了单井回灌效率与关键因子的之间的拟合方程及多元线性回归方程,得到了单井回灌效率与关键因子之间的定量关系。  相似文献   
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A new type of three dimenstional inner microfin tube is devoloped. Under four different pressures and in the range of condensing mass velocities from 33 to 153 kg/m2 . s,and by the experimental study of the three kinds of tubes with different microfin parameters, the performances of the condensation heat transfer for R11 in the horizontal microfin tubes and obtained. The experiments show that the inner microfin tube is a hopeful and nighty effective condensing heat transfer enhancement tube.  相似文献   
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:In accordance with the problems, occurred in the mountainous city's construction, especially the crises such as the destruction of ecological and humanistic environment, the loss of traditional culture and characteristics and the disorder of urban structure, this paper discusses the distinctive landscape characteristic of mountainous city thoroughly.  相似文献   
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This paper analyses the thermal moist characteristics of the hull layer beside an air layer at lower temperature in an envelope for a cold storage and presents a new method of waterproof by air layer. With test data from engineering practice, the theory on the barrier of self moisture proof at the surface sublayer of the hull layer in an attic on a cold storage is proven. The dried zone about three phase point is confirmed. It is a new knowledge for thermophysics on thermal design of a cold storage with an optimum thermal performance.  相似文献   
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论压弯构件     
杨卓 《湖南农机》2007,(7):170-171
钢筋混凝土轴心受力构件、受弯构件和偏心受压构件在力学行为上有一个共同的特征,即构件的材料纤维均处于单向应力状态。为便于分析比较,特将这三类构件的力学性能一起讨论。  相似文献   
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AIM To investigate whether microRNA-9-5p (miR-9-5p) mediates sympathetic overactivity by targeting KCNN3 (potassium intermediate/small conductance calcium-activated channel, subfamily N, member 3) gene,which encoded small-conductance calcium-activated potassium channel 3 (SK3) protein, in paraventricular nucleus (PVN) of rats with type 2 diabetes mellitus (T2D). METHODS A rat model of T2D was established by high-fat diet combined with intraperitoneal injection of 30 mg/kg streptozotocin. The levels of miR-9-5p and KCNN3 mRNA in PVN were detected by real-time PCR. The relationship between KCNN3 and miR-9-5p was predicted by TargetScan. Recombinant adeno-associated virus (rAAV)-miR-9-5p or KCNN3 were bilaterally microinjected into the PVN to observe the changes in plasma glucose levels and sympathetic drive indicators. The number of FosB and SK3 positive cells was measured by immunofluorescence staining. The protein expression of SK3 was determined by Western blot. The relationship between KCNN3 and miR-9-5p were confirmed by cell transfection and dual-luciferase reporter assay. RESULTS Compared with the rats in diabetes control (DC) group, the blood glucose, sympathetic drive indexes and the level of miR-9-5p in PVN were significantly increased, while the SK3 expression in PVN was obviously reduced in the diabetes mellitus (DM) rats. After microinjecion of rAAV-miR-9-5p in PVN, the sympathetic drive indexes, blood glucose, and the number of FosB-positive cells were increased significantly, but the SK3 protein expression was significantly reduced (P<0.05). However, up-regulation of KCNN3 in PVN had the opposite effect. These responses were obviously enhanced in DM rats compared with DC rats. The results of cell transfection and dual-luciferase reporter assay demonstrated that miR-9-5p bound to the 3’-UTR of KCNN3 and inhibit its expression. CONCLUSION miR-9-5p was up-regulated in PVN of the rats with T2D, and it may mediate sympathoexcitation by targeting KCNN3.  相似文献   
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白居易的园林情结及其对传统私家园林的影响   总被引:1,自引:0,他引:1  
白丹  闫煜涛 《广东园林》2007,29(3):8-10
本文阐述了唐朝诗人白居易的园林情结,剖析其园林思想,并归纳他的“中隐”思想和朴实造园手法对传统私家园林产生的深远影响。  相似文献   
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