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71.
利用赌博机赌博案件的作案手段隐蔽、发现查处难度大、涉及人员多、社会危害性大,是群众反响强烈的难点问题。本文从分析现场取得百家乐1号赌博机的电子证据入手,通过电子数据检验鉴定,从而全面掌握涉案赌博机的非法所得情况。 相似文献
72.
基于Web的亚热带水果产品质量安全追溯系统关键技术研究 总被引:5,自引:0,他引:5
徐龙琴 《计算机工程与设计》2011,32(4):1174-1177,1189
为了实现对亚热带水果"从果园到餐桌"全方位的跟踪和追溯,分析了水果产品生产流程并确定了影响其质量的关键点,以产品生产批次作为"身份标识",采用UCC/EAN-128编码方式结合流程编码、RFID和二维码等编码技术进行了追溯编码,并采用任务与角色相结合的权限分配策略,构建了一个多层次多用户权限动态管理的亚热带水果生产加工全过程的质量跟踪与追溯系统,为生产者、质检部门和消费者提供一个集产品生产加工诸环节的信息交流平台,并以网络、语音、短信、触摸屏向公众提供追溯查询和防伪服务,具有应用推广价值。 相似文献
73.
本文提出一种基于细菌迁徙的自适应果蝇算法(CAFOABM),用于求解净化除钴过程锌粉添加量优化设定问题.首先从净化除钴的反应机理出发,通过引入除钴率建立锌粉添加量与氧化还原电位值、出口钴离子浓度间带约束的非线性优化设定模型;为了避免果蝇算法在迭代寻优过程中出现停滞现象,CAFOABM引入多种群并行搜索策略和改进搜索算子对搜索状态的转移规则进行改进;并采用区分可行解与不可行解法进行约束处理,保留一定比例的不可行解个体,有效避免了有用解信息的丢失.实际生产数据验证结果表明,CAFOABM算法优化设定的锌粉添加量与人工操作的经验数据相比减少7.83%,出口钴离子浓度满足实际生产要求且趋于平稳. 相似文献
74.
Liquid chromatography coupled to mass spectrometry (LC-MS) is an excellent technique to determine trace levels of polar and thermolabile pesticides and their degradation products in complex matrices. LC-MS can be equipped with several mass analyzers, each of which provides unique features capable to identify, quantify, and resolve ambiguities by selecting appropriate ionization and acquisition parameters. We discuss in this review the use of LC coupled to (quadrupole) time-of-flight mass spectrometry (LC-(Q)ToF-MS) to determine the presence of target and non-target pesticides in water and food. This technique is characterized by operating at a resolving power of 10,000 or more. Therefore, it gives accurate masses for both parent and fragment ions and enables the measurement of the elemental formula of a compound achieving compound identification. In addition, the combination of quadrupole-ToF permits tandem mass spectrometry, provides more structural information, and enhances selectivity. The purpose of this article is to provide an overview on the state of art and applicability of liquid chromatography time-of-flight mass spectrometry (LC-ToF-MS), and liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS) for the analysis of pesticides in environmental matrices and food. The performance of such techniques is depicted in terms of accurate mass measurement, fragmentation, and selectivity. The final section is devoted to describing the applicability of LC-(Q)ToF-MS to routine analysis of pesticides in food matrices, indicating those operational conditions and criteria used to screen, quantify, and identify target and "suspected" pesticides and their degradation products in water, fruits, and vegetables. The potential and future trends as well as limitations of LC-(Q)ToF-MS for pesticide monitoring are highlighted. 相似文献
75.
以玉米碴为原料,分别选用UV-48黑曲霉和啤酒酵母为发酵菌种,通过对接种量、培养温度、pH值以及发酵周期的研究,确定以玉米为原料制作黄酒的最佳发酵条件为:最适接种量为糖化菌10%,酵母菌1%;最适发酵温度为15-18℃;最适pH值为4.5-5.5,最适发酵周期为16-19d。 相似文献
76.
77.
W. P. Ponce J. L. Nation T. C. Emmel B. J. Smittle P. E. A. Teal 《Journal of chemical ecology》1993,19(12):3045-3056
Pheromonal volatiles emitted by irradiated and control 5- to 11-day-old Caribbean fruit flies,Anastrepha suspensa (Loew), were collected on Tenax adsorbent filters and quantified by gas chromatography (GC). The components released were identified by comparison of retention times on GC and by mass spectrometry (MS) with authentic synthetic standards. Pharate adults were irradiated with gamma rays from a60Co source at a dose rate of 10.3 Gray (Gy)/min. The total dosages given were 30, 50, 70, and 100 Gy. Pheromone volatiles were collected from adult males when they were between 5 and 11 days of age. The compounds quantified were (Z)-3-nonenol and (Z, Z)-3,6-nonadienol, which eluted from the GC column together and were quantified as one peak,-bisabolene, suspensolide, anastrephin, and epianastrephin. Irradiation with 30 Gy did not significantly reduce any pheromonal components, nor did it change the pheromonal blend. In contrast, suspensolide and bisabolene were significantly reduced in flies irradiated with 50 Gy, while the nonenols and epianastrephin were reduced at the 70-Gy dose. Irradiation with the 100-Gy dose reduced all components with the exception of suspensolide.University of Florida Agric. Exper. Sta. Journal Series No.R-03156. 相似文献
78.
A method has been derived which permits the determination of the degree of ploidy in industrial strains of yeast. The method involves measuring the DNA content per cell of the strains, which is achieved by careful counting of the cells using a haemocytometer and a determination of the amount of DNA by a colorimetric method. Using this technique it was determined that the two industrial lager strains under investigation are tetraploid. * 1 These results have been briefly described at the meeting of the EBC Subgroup on Yeast Genetics, Copenhagen 1982.
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79.
为解决农作物病虫害的诊断问题,选择京郊常见果树的三种害虫:桃蛀螟成虫、华北大黑鳃金龟成虫、桃六点天蛾,使用计算机视觉技术清除背景,获取该害虫的形状参数、偏心率等形态特征。通过判别分析,建立三种害虫形态特征的判别评分函数,并测试了该判别评分函数的有效性。实验结果表明,形状参数、偏心率、似圆度特征能反映这三种害虫的形态特点,可有效区分这三种害虫。 相似文献
80.
从大连海域的海参肠道中筛选得到一株产胞外多糖较高的酵母菌HS-J9,经形态学和26SrDNA序列分析,初步鉴定为季也蒙假丝酵母(Meyerozyma guilliermondii),GenBank检索号为KF668241。采用苯酚-硫酸法和响应面法对该高产菌株进行胞外多糖测定及发酵条件优化。通过单因素试验确定了pH、接菌量和发酵时间3个主要因素对发酵产糖量的影响,根据Box-Behnken中心组合设计原理确定显著性因子的最佳水平,并以胞外多糖产量为响应值进行回归分析。结果表明,当pH为6.6、接菌量4%、发酵时间41.3h时,HS-J9的胞外产糖量最大,为0.762 mg/mL,比优化前的产胞外多糖量(0.616mg/mL)提高了23.67%。 相似文献