群众渔船柴油机废气余热利用的研究

我国能源利用率较低，只有28％左右，而世界先进国家达40％。因此如何提高我国能源利用率，节约能源，提高经济效益和社会效益，是我国发展国民经济的一件大事。我国水产系统耗能的分配比例，海洋捕捞占总能耗70％左右，主要是渔船的柴油机耗能。目前我国海洋捕捞渔业中，群众渔船的总功率占95％以上，因此研究群众渔船的节能，     

Sediment Load in Runoff Under Laboratory and Field Simulated Rainfall

Soil erosion is one of the most important problems in the Loess Plateau of China affecting sustainable agriculture. Near Luoyang (Henan Province, China), field plots were constructed to measure soil erosion rates under conventional tillage practices using field-simulated rainfall.Field rainfall experiments were carried out to compare previous results from laboratory rainfall simulations on the same soil for interrill conditions. Although in the laboratory experiments, a strong correlation was found betweenthe stream power of the runoff water and the unit sediment load, this sediment transport equation overestimated the field rainfall simulation results. Another sediment transport equation derived by Nearing et al. for rill erosion was in better agreement with the results of the field experiments, although it also overestimated these values. The measured sediment load values during the field rainfall simulations were also lower than those found during field experiments on the same soil but with a loosened surface layer. This difference indicates the importance of soil physical condition of surfce like soil structure and aggregate size, which may contribute to the discrepancy between the field and laboratory experiment results.     

锤片式粉碎机主参数的确定及对性能的影响

1 配套动力N的确定 在设计粉碎机时所需功率N是根据粉碎室宽度B、转子直径D的比值K=N/(B·D)。在我国其值一般取K=(8-15)×10 -5 kW/mm2。2 锤片末端线速度V的确定 V增大时增强锤片对物料的打击、搓擦和磨碎作用,能增加粉碎能力和产品细度,但V过大会使机器的空载功率增加,同时因转子不平衡产生的噪音和振动也随之增     

耦合电路功率的传输

耦合电路，即互感器，在电力系统中应用相当广泛，象各种变压器、互感器等等。具有互感的耦合电路，其基本原理是对一个线圈加激励(电压源或电流源)，由于磁通的角链在另一个线圈上则感应出     

研究森林变化对河川水沙影响的一种便捷方法──以四川省都江堰市白沙河为例

依据航片判读、森林资源调查资料和水文数据，利用流域自身对比法，得出森林变化对河川径流泥沙的定量关系。文中还阐明本方法的技术关键——消除降雨量不同对水沙的影响．该方法具有适合我国国情、费小效宏、精度较高、简捷易行等优点，值得推广提倡。     

天然沙棘林减水减沙效益试验研究

利用人工降雨机在天然沙棘林内进行百年一遇短历时降雨试验,测得荒坡径流、侵蚀量分别为39 300m~3/km~3和865t/km~2,而郁闭度0.7的沙棘林径流侵蚀量分别比荒坡减少88.67％和99.03％。郁闭度越大,减水减沙效益越显著。当郁闭度>0.5时减水减沙效益迅速提高。在沙棘林减水减沙效益中,林地枯落物层和根系层占主导地位,林冠层的作用相对较小。