Study of Tooth Contact and Kinematic Precision on Cone-Generated Double Enveloping Worm Gearing

The tooth contact and kinematic precision of cone-generated double-enveloping worm gearing with machining and assembling errors have been investigated. The influence of different errors on driving quality has been discussed. The assembling method to reduce or eliminate the influences of machining errors on tooth contact and kinematic precision has been proposed.     

Modeling of Liquidus Temperature for Al-Si Cast Alloys with Adaptive Neuro-fuzzy Inference System

During the melting and processing practices, an accurate knowledge of liquidus temperature is necessary in the determination of process parameters relating to a given alloy. Adaptive neuro-fuzzy inference system (ANFIS) modeling method has been used to improve accuracy of prediction for liquidus temperature based on the compositions of Al-Si series cast alloys. The developed fuzzy inference system could extract Takagi-Sugeno type fuzzy rules from data directly, and has a feed-forward network structure with supervised learning capability. In order to adapt the parameters of the model, the proposed fuzzy inference system is trained over a wide range of compositions from the published data of industrial alloys. The result shows that, the developed ANFIS model can capture non-linear relationships between compositions and liquidus temperature, and then provides better prediction than the reported multiple statistic analysis. The developed model can be used to predict the liquidus temperature needed in computer modeling and thermodynamic calculation, which are needed in the aluminium alloys casting industry and research.     

棉铃虫卵、天敌与产量的关系及其防治指标的研究

从棉铃虫卵量、天敌和棉花产量三者之间的关系入手 ,进行了 3代 (主害代 )棉铃虫防治指标研究。研究结果表明 :在卵高峰期一次性调查百株卵量和天敌单位数 ,当卵粒数减去天敌单位数的 2 2倍之后 ,其值≥ 8时 ,即达防治指标     

锥面二次包络环面蜗杆副的修形

建立了锥面二次包络环面蜗杆传动啮合分析的数学模型，引入了生产中便于实现的各种修形参数，总结出确定修形类型的规则，编制了啮合分析软件包，提出求解齿面实际接触区域的方法，并根据相位分析法研究了各种类型传动的齿面结构，分析了蝇杆边齿变尖和根切的影响因素。对标准传动进行了全面的啮合分析，首次对△b修形传动进行了研究，并对Ⅰ型和Ⅱ型修形传动进行了啮合分析。理论计算的齿面接触区域与实验获得的齿面接触印痕相符。     

2种氯化烟碱类杀虫剂不同处理方法对蚕豆蚜的毒力测定研究

为了明确杀虫剂毒力与其测定方法间的关系,选取蚕豆蚜为试验对象分别采用浸渍法、离体喷雾法和连续浸液法测定噻虫嗪和呋虫胺的毒力。结果表明,噻虫嗪浸渍法和连续浸液法对蚕豆蚜的毒力显著高于离体喷雾法;呋虫胺浸渍法对蚕豆蚜的毒力显著高于离体喷雾法和连续浸液法。由此可知,同种药剂不同测定方法与其毒力的表达结果具有显著的相关性。     

Regional and annual trends in Douglas-fir foliage retention: Correlations with climatic variables

Swiss needle cast imposes strong geographical patterns in Douglas-fir needle retention throughout the Coast Ranges of Oregon and southwestern Washington. These geographical patterns in foliage retention have been related to the spatial variability in average climatic conditions, with climate presumed a major causal factor in the spread and intensification of the fungus that causes Swiss needle cast. Annual fluctuations in foliage retention have likewise been hypothesized to follow fluctuations in annual climatic conditions. The objective of this analysis was to test a full suite of climatic variables for their ability to predict regional and annual patterns in Douglas-fir foliage retention on 296 permanent sample plots comprising six different Swiss needle cast studies. Foliage retention was estimated annually from 1996 to 2009 and climatic data were generated from the PRISM website through ClimateWNA (Wang et al., 2006). Among the 85 annual, seasonal, and monthly climate variables explored, average foliage retention was predicted most consistently by a temperature-based continentality index, mean annual precipitation, winter temperature, summer temperature, and spring or summer precipitation. The same 85 variables were tested for predicting annual fluctuations in foliage retention, allowing for lagged effects of climatic conditions 1-4 years prior to each year of observation. The annual foliage retention models had climate variables similar to the periodic average foliage retention models, but with a variety of lagged effects. The periodic average foliage retention model suggested that under future climate scenarios foliage retention would increase.     

Nonmetallic Inclusions in Continuous Casting Slab

In order to improve the quality of the products and the pure degree of the steel; the type, quantity, size, composition and distribution of the nonmetallic inclusions present in continuous cast slabs made by Weiyuan Iron and Steel Co. , Ltd. are investigated with optic microscope, SEM, XES and Electroanalysis. Moreover the original of the inclusions is discussed. The result shows the inclusion in the continuous cast slab is mainly the spherical silicate inclusion which is smaller than 10 um. There is a small amount of polygonal inclusions, and there is the single-phase one and heterogeneous inclusion too; And the inclusions assemble in 1/3 position and in 1/4 at board base thickness and width direction. The inclusions are ineral, which origin from the deoxidizing process of molten steel.     

THE METHOD OF THE MEASUREMENT OF THE WORMWHEEL PROFILE ERROR WITH THE THREE-COORDINATE-MEASURE-MACHINE

In this paper we explain the method of the measurement of the wormwheel profile error with the three coordinate measuring machine. We first establish the wormwheel theoritical tooth profile equation according to the gear engage principle, then write the computing program and calculate the wormwheel theoritical profile, next analyse and calculate the error of the gage head interference. At last, we work out the measuring program and get the wormwheel profile measured with the three-coordinate measuring machine.     

The influence of slug (Arion rufus) mucus and cast material addition on microbial biomass,respiration, and nutrient cycling in beech leaf litter

We investigated the effects of slug (Arion rufus L.) mucus and cast material on litter decomposition, nutrient mobilization, and microbial activity in two laboratory experiments: (1) Slug mucus and cast material was added to beech leaf litter (Fagus sylvatica L.), and leaching of N and P and CO₂ production in microcosm systems were measured during 77 days of incubation; (2) mucus was added to beech leaf litter, and basal respiration, microbial biomass (substrate-induced respiration), specific respiration (qO₂), microbial growth ability after C, CN, CP, and CNP amendment, and lag time (time between CNP addition and start of exponential increase in respiration rate) were measured during 120 days of incubation. Leaching of N and P from beech leaf litter was significantly increased in treatments with mucus or faecal material of A. rufus. Following day 3, slug mucus increased nitrification processes. Mucus addition to beech leaf litter also increased basal respiration and microbial biomass significantly. In contrast, specific respiration was not significantly affected by mucus addition, and generally declined until day 60 but then increased until day 120. Nutrient amendments indicated that between days 1 and 30, N was available for microbial growth in litter with mucus but not in control litter. Generally, the lag time in beech leaf litter with added mucus was shorter than in control litter. Lag times generally increased with age, indicating dominance of slow-growing microbial populations at later stages as a consequence of depletion of easily available C resources and nutrients. We conclude that C, N, and P cycling is accelerated by slug activity.     

铝渣复合脱硫剂的研究

本文研究了利用炼铝过程产生的铝渣、辅以石灰、萤石作为炼铁用的新型脱硫剂，通过对可锻铸铁进行炉外脱硫的正交试验，得出其优化配方为：ＣａＯ５１％，铝渣３９％，Ｆ２１０％。精炼时熔渣碱度高、流动性好，可使可锻铸铁脱硫率达到３３．５－３７．５％。