Improved scheme for spectrum allocation in cognitive wireless sensor networks

In order to effectively allocate the idle spectrum and improve spectrum utilization of cognitive wireless sensor networks, it is necessary to design an efficient spectrum allocation algorithm. Aiming at the problem of spectrum allocation in cognitive wireless sensor networks, an improved method for spectrum allocation is suggested. A new chaotic dynamic clonal evolution algorithm is designed. Then the graph theory coloring model is established with the corresponding fitness function derived. Traditional evolutionary algorithms have the problem of premature convergence, so chaotic operators, adaptive operators and cloning operators are added to the traditional evolutionary algorithms to accelerate the convergence of the algorithm. The chaotic dynamic clonal evolutionary algorithm is compared with the simulated annealing algorithm and the ant colony algorithm by simulation. The simulation results show that compared with the ant colony algorithm and the simulated annealing algorithm, the chaotic dynamic clonal evolution algorithm can effectively improve the global search ability, and significantly improve the network benefit value of spectrum allocation. The results also show that the proposed chaotic dynamic clonal evolution algorithm can make full use of existing spectrum resources and improve the system throughput.     

浅析水利枢纽工程对叶尔羌河流域经济发展的影响

水利枢纽工程可以实现对水资源的统一调配, 提高水资源利用率, 改善工程所在地区用水状况.本文以新疆下坂地工程为例,通过探讨其在解决叶尔羌河流域灌区春早补水问题、提供电力补偿和改善生态环境等方面所起到的巨大作用,以及由此带来的经济效益,说明了水利枢纽工程对流域经济的发展有着显著的推动作用.     

不同负载量对霞多丽葡萄生长发育及酿酒品质的影响

为探索不同负载量对葡萄及葡萄酒品质的影响,对8年生霞多丽进行了不同负载量试验。结果表明,合理降低负载量能提高葡萄品质,增加果实含糖量,葡萄酒感官品质也显著改善;以留穗数为10穗/株(产量700.3kg/667m2)和15穗/株(产量1028.9kg/667m2)处理较优,负载量过大表现较差。综合分析,霞多丽葡萄的适宜负载量为700～1000kg/667m2。     

地基处理课程实践教学改革研究

地基处理课程涉及的知识体系庞杂,是系列岩土课程群的总结课程之一。在厘清地基处理课程体系特点的基础上,提出了适合地基处理自身特点的教学思路及其实践教学改革方法,为今后地基处理课程教材的编写及课堂教学提供借鉴。     

化学工程与工艺专业本科层次卓越工程师计划校企联合培养模式的研究

针对新疆地区化工人才的需求,文章从卓越工程师的培养目标,培养模式及实施计划的保障措施三个方面,探讨了石河子大学与疆内相关化工企业深度开展校企联合培养化学工程与工艺专业卓越工程师教学模式,相信该教学改革模式的实施和实现将会为高校化学工程与工艺专业卓越工程师人才的培养与改革提供参考与借鉴。     

氢氧化镁有机化改性研究

采用甲基丙烯酸甲酯为改性剂改性氢氧化镁,研究了引发体系的选择、复合乳化剂的用量、MMA与Mg(OH)2的用量、反应温度对吸油值的影响。结果表明,以过氧化苯甲酰为引发剂、复合乳液用量为1.5 g/L、MMA/Mg(OH)2为7/3~6/4、反应时间为3 h、反应温度为70℃时,改性Mg(OH)2吸油值最小,为31%。并对最佳条件下改性样品进行了扫描电镜表征。     

Distribution of polycyclic aromatic hydrocarbons in snow of Mount Nanshan,Xinjiang

Polycyclic aromatic hydrocarbon (PAH) in snow samples collected from Mount Nanshan (Xinjiang, China) was investigated for eight stations. Fourteen PAHs were detected in these samples. The total PAH concentration ranged from 70.15 ng/L to 155.67 ng/L, with an average of 113.02 ng/L. Human carcinogens, such as fluoranthene, chrysene, benzo(a)pyrene, dibenzo(a,h)anthracene, indeno(1,2,3‐cd)pyrene and benzo(ghi)perylene in snow were assessed based on risk quotient. Preliminary assessment showed that these PAHs posed a moderate risk. Component analysis showed that the PAHs found in the snow samples were mainly three‐ring PAHs, which comprised 34.51–90.81% of the total PAHs. Phenanthrene, fluorene and anthracene accounted for 35.08, 11.90 and 11.13% of the total PAHs, respectively. The ΣPAH content increased with the increasing altitude, and the highest concentration of 155.67 ng/L was observed in snow samples from the N7 station, which was located near the top of the mountain. This high PAH concentration in N7 was possibly due to more frequent human activities in the area and long‐distance transportation of PAHs. Isomer ratios were used to determine the possible sources of PAHs in the samples. The results indicate that coal and biomass combustion made a larger contribution than emissions from petroleum consumption. It is therefore of utmost importance to develop new fuels taking the place of coal and to achieve as complete as possible for the burning of carbon‐containing materials.     

基于水资源优化配置多目标决策模型探析

水资源优化配置问题是一个多目标决策问题,该文在分析水资源优化配置基本概念及内涵的基础上,依据水资源配置的原则及目标,对基于经济目标、环境目标与社会目标的水资源优化配置多目标决策模型进行了较为深入的分析,并探讨了模型的求解及决策方案的选择,可为水资源优化配置多目标决策问题提供一定的理论和实践指导。     

梅奇酵母氨基甲酸乙酯酶分离纯化与酶学性质分析及其对葡萄酒香气的影响

为了研究梅奇酵母所产生氨基甲酸乙酯（Ethyl Carbamate,EC）酶的性质,通过硫酸铵盐析、离子交换层析的方法对EC酶进行分离纯化,并对纯化后EC酶的酶学性质进行了分析。结果表明,纯化后EC酶对比纯化前的酶活提高了约1.2倍。纯化后EC酶最适反应温度为35 ℃,在25~45 ℃之间热稳定性较强;最适pH为5.5,在pH5~6时该酶稳定性强,即酸稳定性强,碱稳定性较差。当乙醇体积分数为12%~14%时,EC酶具有一定酶活。底物特异性结果表明,该EC酶对EC及其前体物质（尿素）具有较高的降解能力,且对于成品葡萄酒挥发性香气成分影响不显著。     

新疆传统乳品中乳酸菌的抗氧化能力

实验用菌为从新疆传统乳制品酸奶和干酪中分离出的7株乳酸菌,分别是乳酸片球菌(Pediococcus acidilactici)1株、植物乳杆菌(Lactobacillus plantarum)3株、耐久肠球菌(Enterococcus durans)1株、魏斯氏菌(Weissella cibaria)1株和面包乳杆菌(Lactobacillus panis)1株。对其清除DPPH自由基、超氧阴离子自由基、羟自由基、还原能力以及亚铁离子螯合能力进行了研究。结果表明:7株乳酸菌具有不同的抗氧化能力,其中植物乳杆菌亚铁离子螯合能力最强,乳酸片球菌超氧阴离子自由基清除能力相对较高,魏斯氏菌的DPPH自由基清除能力较强,面包乳杆菌的羟自由基清除能力和还原能力最强。