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991.
首次提出了用频率谱分析法分析墙体表面换热过程及推导墙体表面换热系数的实验方法。经实验和预测检验表明:该方法能够充分反映墙体表面换热过程,其结果是准确可靠的。为确定墙体表面换热系数找到了一种实用有效的方法。 相似文献
992.
对不同品种茎用芥菜的瘤状茎在膨大过程中细胞壁成分的研究表明,瘤状茎在膨大过程中,细胞壁中果胶、半纤维素2、纤维素、醛酸和总糖含量逐渐下降,特别是膨大后期下降幅度较大.其中,果胶和总糖含量不同品种间差异较大,纤维素的含量在膨大后期,不易空心品种T84-61高于易空心品种T84-66.β-1,3-葡聚糖含量在膨大后期不易空心品种T84-61高于易空心品种T84-66,这与膨大后期T84-61品种β-1,3-葡聚糖合成酶活性增加有关.瘤状茎中的Ca含量T84-61品种在膨大后期高于T84-66,而Mg含量品种间无明显差异.由此可见,细胞壁中果胶、总糖、Ca和β-1,3-葡聚糖含量的降低,可能与瘤状茎空心的形成有关 相似文献
993.
Summary The development of the pollen mother cells (PMC's) and anther wall of a male-sterile mutant was microscopically compared with that of fertile sib plants in pigeon pea (Cajanus cajan). Male-sterility was complete and caused by breakdown of microsporogenesis at prophase I. Delayed and incomplete development of the anther wall appeared to be responsible for PMC degeneration. The sterile mutant also differed from the fertile plants in the size and number of the PMC's.On leave from International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, India. 相似文献
994.
In order to research the potential of energy efficiency design of public building in depth, the large scale of store building in urban districts of Chongqing is chosen as the subject. On the basis of investigation into typical department store,an elementary model of department store has been built up. In allusion to exterior wall of department store, in respect of improving heat preservation of exterior wall, four different energy efficiency conformation design projects were made out,such as using double-layer window and adding heat insulation layer to exterior wall etc. and four energy efficiency projects with the actual design of exterior wall were compared;By analyzing the thermal and economic indexes, the most effective project of the energy efficiency design of exterior wall as to store building was found out to provide reference to the energy efficiency design of large scale of public building. 相似文献
995.
Luo Wankang 《保鲜与加工》1994,(4):52-66
By comparing the tests of prestressed and nonprestressed brick masonry walls with peripheral beams and Constructional columns, under cyclic lateral loading,the apperaence and development of Cracks,failure mechanism,hysteretic behavior,strength,stiffness,ductility and ener-gy dissipation of the brick rnasonry walls arc studied.Only the crack resistance and bearing capacity of walls are discussed in this paper.It is shown that prestressing on brick masonry wall can obviotisly improve its seismic behavior.Morcover,calculating methods for the crack resistance and the ultimate bearing capacity are presented,and the caculating results are identical with the tests. 相似文献
996.
997.
PH3和CO2 混合熏蒸及微气流熏蒸试验在砖结构的立筒仓中进行。试验表明 ,微气流熏蒸时PH3保持有效浓度的时间远远长于混合熏蒸。混合熏蒸PH3易渗漏的原因之一是仓内气体压力较高。本文还对混合熏蒸药剂的渗透力及立筒库熏蒸方法的选择进行了讨论 相似文献
998.
Summary A simple technique for counting mitotic chromosome numbers in ovaries of inflorescences has been developed and applied to grasses. The uses, as outlined, include isolating polyploid inflorescences for hybridization, and as an alternative method to root-tip squashes for chromosome morphology and banding studies. 相似文献
999.
In this study we tried to develop an analysis program that can simulate the collapsing process of timber-frame structures under dynamic loading by adopting the extended distinct element method (EDEM). Using the EDEM, it is possible to trace the movement of any parts that were separated from unity after the failure of connecting elements, a property that fits our purpose well. As a preliminary study, simple two-story frame structures were modeled and examined by our program. Each model is an assembly of frame members composed of the EDEM elements. The spring elements of the joints have less rigidity than those of the frame members. Several models were analyzed under dynamic loading. The models varied in the configuration of bracing shear walls. Experiments with a one-ninth model were carried out under similar conditions, and the results were compared with the results from numerical simulations. Simulated results showed various collapsing processes corresponding to the arrangement of the bracing shear wall, and the simulated aspects gave good agreement with the results of the experiments under similar conditions.Part of this paper was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000 相似文献
1000.