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根据力学的基本原理，通过对转子不平衡量的测量，利用单片机及接口技术，结合非电量信号采集与处理的知识，对原来的动平衡仪进行重新设计改造。本文介绍了其测试原理，单片机硬件系统，及其系统软件的实现。 相似文献
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湿地淡水资源供给是一项重要的生态系统服务功能,主要包括城镇居民生活用水、工业(矿业)用水和农业用水三大部分。以2013年吉林省湿地淡水供给资源作为研究对象,采用市场价值法,进行省域尺度上与人类生活、工业生产等关系密切的淡水供给服务识别与核算,研究吉林省不同湿地类型和不同行政区的淡水资源供给量和淡水资源供给价值,分析其淡水资源供给的空间分布及其贡献率。结果表明,2013年吉林省湿地淡水资源供给总量为20.81×10~8m~3,其中湖泊湿地、河流湿地、人工湿地和沼泽湿地供给淡水量为8.06×10~8m~3、6.04×10~8m~3、4.00×10~8m~3和2.71×10~8m~3;核算吉林省湿地淡水资源供给总价值为83.84亿元/年,其中湖泊湿地占38.73%,河流湿地占29.01%,人工湿地占19.25%,而沼泽湿地所占比例最小,仅13.01%。在各组成城市中,湿地淡水资源供给价值以松原市最大,核算价值为26.28亿元/年,占总价值的31.34%;白山市最小,为2.6亿元/年,占总价值的3.11%。利用价值量化的方法表征淡水供给为吉林省发展提供的经济价值,对区域水资源优化配置、促使社会经济和生态环境协调发展以及湿地保护具有重要的理论和现实意义。 相似文献
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今年以来,由于我国经济持续发展以及人民生活水平明显提高,对木材制品仍然保持着强劲的需求.尽管国内木材资源供应较比往年有所增加,但是本土木材品种单调,结构矛盾突出,材质水平不高,很难满足国内各行各业对木材的综合需求,所以今年我国木材初级产品(原木、锯材)进口的形势一直保持稳定增长的趋势.总体特点是数量增加、价格回升. 相似文献
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Effect of Organic Manure Application on Physical Properties andHumus Characteristics of Paddy Soil 总被引：5，自引：0，他引：5
Long-term field experiment was established in 1978 on a coastal paddy soil to determine the effect of application of pig manure, rice straw and chemical N fertilizer on the physical property and humus characteristics of soil. Results showed that the porosity, the microstructural coefficient, the reactivities of organic C and N, the OlogK value, the degree of oxidation stability, the contents of o-alkyl C and alkyl C, and the ratio of aliphatic C to aromatic C of humic acid from soils received organic manure increased; whereas, the ratio of<10μm to >10μm of microaggregates, the humification degree of humus, the degree of organo-mineral complexation, the number-average molecular weight, the C/H ratio, the contents of carboxyl and aromatic C of HAs in them decreased. These results indicated that the application of organic manure not only improved the physical property of the paddy soil but also made the HA more aliphatic in structure and younger in origin. 相似文献
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Abstract. Aeromonas salmonicida ssp, salmonicida is shown to produce several extracellular proteins having gelatinolytic activity. Among the six isolates tested, two (NCMB 1102 and 84–14–R) produced both high (89–100 kDa) and low molecular (37 kDa) weight gelatinases, while the other four demonstrated only the 89–100 kDa forms. The low molecular form (metalloprotease 1: MP 1, 37 kDa) was isolated by ammonium sulphate precipitation, hydrophobic, ion exchange and size exclusion chromatography. The isolated enzyme was inhibited by the metal-chelating agents o-phenantroline and EDTA, and by excess Zn ions, and thus was defined as a metalloprotease. Its pH-optimum was 7–5, optimal activity was at 40°C and its pI 5.2. Specificity studies demonstrated cleavage of gelatin and azocoll, but not casein. 相似文献
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经室内饲养和石榴园系统调查表明,井上蛀果斑螟成虫多于20∶00~24∶00 羽化,40 h时后交配,交配高峰期为早晨5∶00~7∶00,一般于交配66h后产卵,成虫喜将卵产于石榴花或果实的萼筒周围以及果实表面的不光滑处。此外,首次较详细地记述了该虫2龄幼虫的毛序特征及雌雄蛹的形态差异,为该害虫的田间快速鉴定提供了依据。 相似文献
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Effect of Pig Manure Application on Structural Characteristics of Humic Acids in Brown Soil 总被引：1，自引：0，他引：1
The effect of application of pig manure (PM) on the structural characteristics of humic acids (HAs) of brown soil was studied in field and incubation experiments.The results showed that the number-average molecular weights (Mn),the ratios of C/H,C/H and O/C,the contents of carboxyl and phenolic hydroxyl groups,the content of aromatic C,the values of E2,E4 and λExmax of HAs all decreased;whereas,the contents of alkyl C and O--alkyl C,the ratio of carboxyl to phenolic hydroxyl groups,the degree of oxidation stability,te absorption intensity at 285mμ (UV),and 2920cm^-1 of HAs increased after the application of PM.The above results indicated that the molecular structure of HAs tended to be more aliphatic and simpler after the application of PM. 相似文献
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将Bradyrhizobium japonicum HN32菌株中的外源质粒pHN32,通过三亲本杂交转入大肠杆菌HB101中,继而转入Bradyrizobium japonicum22—10中,得到一系列抗性杂交子HNF1,HNF3及HNF5,检测其中所含质粒,并以22—10,HNF5及HN32进行盆栽试验,pHN32的增效作用得到了证实。 相似文献