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41.
通过对淮北市五马路沿线2块夏大豆的田间调查分析表明:受路灯照射的影响,夏大豆株高增加,开花期、成熟期推迟,底荚部位上升,单株生产力下降.且距离越近,植株越高,开花、成熟越晚,底荚部位越高,单株生产力越低. 相似文献
42.
对北京市新型农村合作医疗制度的调查与思考 总被引:1,自引:0,他引:1
李香允 《北京农业职业学院学报》2007,21(5):53-57
自2002年7月北京市大兴区率先在全国开展新型合作医疗试点至今,北京市新型农村合作医疗制度运行已经5年了.在对北京市新型农村合作医疗制度运行情况进行充分调研的基础上,总结了所取得的成效,分析了存在的问题,要进一步完善这项制度应提高筹资水平,实行动态缴费;提高补偿水平,提升制度吸引力;充实管办资源,重视调研能力建设等. 相似文献
43.
44.
目前农村老年人养老现状不容乐观.家庭养老功能弱化,社区养老机制滞后,社会福利、政府救济和低保投入严重不足等,导致绝大多数农村老年人处在家庭边缘和社会保障体系之外. 相似文献
45.
农民负担实际上是与农民有关的公共产品成本的分摊,而这种分摊存在着体制缺陷,这种缺陷导致了农民的生产效益低下,农民负担逐步加重。要改变这种现状就必须对农村公共产品供给体制进行改革和完善,以期从根本上减轻农民负担。 相似文献
46.
By analyzing the pressure distribution between gears and sealing blocks in compound gear pump with three idlers,the resultant hydraulic forces acting on seal blocks are obtained.The conclusion is the unbalanced resultant hydraulic forces are relatively small in magnitude.In the pump,the inner sealing edges are long and so it s Sealing effect is good,but the outer sealing effect is relatively poor because of its short sealing edges.The little unbalanced force pushes the sealing block to te pumping chamber,therefore it is advantageous to meliorating the pump's sealing effect,thereby to improving it's volumetric efficiency as well. 相似文献
47.
Wang Bingle Song Liquan 《保鲜与加工》1988,(2)
This paper presents a new method by using mass and acceleration parameters for balancing inertial force of mechanism. Compared with other balance methods, this one is simple, clear and superior in regularity when the balancing equation of complex mechanism is established, and its solving procedure is also easy. The new methcd is convenient to learn and use as well as convenient to program. 相似文献
48.
The analysis of vibration response of structure with TMD is carried out under earthquake ,considering the ground-structure interaction. The varying rule of square difference of displacement of structure with the TMD on or off by changing the first inherent frequency is also presented .It has been proved by comparing and analyzing that a TMDstructure with optimum parameters can efficiently reduce the vibration of structure under strong wind and earthquake,when the main frequency of the ground motion is within the range of TMD vibration reducing frequency. 相似文献
49.
A new type of inorganic anchoring material is developed as a substitution for anchoring adhesive to overcome some imperfections in the process of planting reinforcing steel bar.The mix proportion of the anchoring material is determined by experiments.The compressive strength,adhesive force to concrete,volume stability and anchoring force with steel bar are studied.The early strength of the anchoring inorganic material is quite high: for 1d up to 38.5MPa and 3d up to 60MPa.It is a good adhesive to concrete and the adhesive strength of 28d is about 2MPa.The anchoring material will have tiny volume expansion with the age,which is beneficial to enhancing the anchoring force.The essential component of the inorganic anchoring material is cement-based material,so some defects of the organic macromolecular material can be avoided,such as poor stability and requirement for vigorous construction conditions.Its characteristics in early strength,adhesive force to concrete and volume expansion can satisfy the requirement of the construction to the planting reinforcing steel bar and the loading force,thus it can be used as a substituting material for anchoring adhesive. 相似文献
50.