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排序方式: 共有2033条查询结果,搜索用时 187 毫秒
1.
高温季节食醋生产中影响酒精发酵的因素及改进措施 总被引:2,自引:0,他引:2
该文以镇江香醋生产为例,分析了高温季节食醋生产过程中影响酒精发酵的因素,并提出了改进措施。 相似文献
2.
中药大蜜丸及所用包装材料软、粘、轻、小、光,较难实现机械化自动包装。通常的监控方法不适合蜜丸的自动包装。采用红外线光电控制器,解决了自动包装蜜丸时出现的瞬间无纸、无丸等自动控制。 相似文献
3.
针对生鲜闭环供应链网络设计问题,建立了一种基于生鲜闭环供应链网络的鲁棒优化模型,以解决供应链网络中的不确定性问题。首先,针对涵盖五个节点的生鲜供应链网络结构建立了多周期、多产品,以最小化成本、最小环境影响为目标的混合整数规划模型,采用模糊折中规划与区间数据鲁棒优化方法进行处理;其次,在原有蜜獾算法的基础上引入差分进化原则,增强算法的全局搜索能力与收敛速度;最后,通过MATLAB数值分析与仿真实例表明,所提鲁棒优化模型与蜜獾算法在求解生鲜闭环供应链网络设计问题中具有明显优势。 相似文献
4.
5.
T. Pankiw M. L. Winston E. Plettner K. N. Slessor J. S. Pettis O. R. Taylor 《Journal of chemical ecology》1996,22(4):605-615
The composition of the five-component honey bee queen mandibular gland pheromone (QMP) of mated European honey bee queens was compared to those of virgin and drone-laying (i.e., laying only haploid unfertilized eggs that develop into males), European queens and Africanized mated queens. QMP of mated European queens showed significantly greater quantities of individual components than all queen types compared, except for a significantly greater quantity of 9-hydroxy-(E)-2-decenoic acid (9-HDA) found in Africanized queens. Glands of European drone-laying queens contained quantities intermediate between virgin and mated queens, reflecting their intermediate reproductive state and age. QMP ontogeny shifts from a high proportion of 9-keto-(E)-2-decenoic acid (ODA) in young unmated queens to roughly equal proportions of ODA and 9-HDA in mated queens. A biosynthetic shift occurs after mating that results in a greater proportion of 9-HDA, methylp-hydroxybenzoate (HOB), and 4-hydroxy-3-methoxyphenylethanol (HVA) production, accompanied by a decreased proportion of ODA. Africanized QMP proportions of ODA and 9-HDA were significantly different from European queens. A quantitative definition of a queen equivalent of QMP is proposed for the various queen types, and a standard queen equivalent for mated European honeybee queen mandibular gland pheromone is adopted as 200µg ODA, 80µg 9-HDA, 20µg HOB, and 2 µg HVA. 相似文献
6.
以甲酚紫培养基中加入乙醇作为分离培养基,从5种水果样品中分离得到20种醋酸菌,然后通过产酸量的测定,筛选出了一株产醋酸度高的醋酸菌AAB13.探讨了乙醇浓度、菌株接种量、发酵液有效体积对醋酸发酵的影响,并在优化的条件下制备了苹果梨醋. 相似文献
7.
本文为解决复杂的随机规划问题设计了一种基于随机模拟的混沌量子蜜蜂算法,证明了该算法的收敛
性,并分析了算法的收敛速度.分析6 自由度空间机器人系统的不确定性,采用基于微分变换法进行误差分析,建
立了随机数学规划模型.为涉及故障前后运动学与动力学约束限制的容错轨迹规划,以加权最小驱动力矩为优化性
能指标,采用混沌量子蜜蜂算法求解全部工作时间中机械臂故障前后的最优轨迹.通过降低异常关节的运动速度来
降低故障关节力矩,保证机械臂在发生故障后具有较高的操作能力.案例研究验证了该算法的有效性、稳定性及准
确性. 相似文献
8.
Chen Yanni Liu Liqiang Xu Liguang Song Shanshan Kuang Hua Cui Gang Xu Chuanlai 《Nano Research》2017,10(8):2833-2844
A gold immunochromatographic sensor (GICS) was developed for the rapid detection of 26 sulfonamides in honey samples.The sensor was based on a group-specific monoclonal antibody (mAb) that can recognize all 26 sulfonamides.Three haptens (hapten 1 with a thiazole ring,hapten 2 with a benzene ring,and hapten 3 with a straight carbon chain) were used for antigen preparation.With hybridoma technology,a group-specific mAb was screened with a 50% maximal inhibitory concentration (IC50) against sulfathizole (STZ) and the other 25 analogues ranging from 0.08 to 90.18 ng/mL.Mono-dispersed gold nanoparticles were conjugated with the mAb to develop the lateral immunochromatographic strip.A labeled antibody concentration of 0.1 μg/mL and a coating antigen concentration of 0.2 μg/mL in the test line were chosen for strip preparation.Under optimized conditions,the visual limits of detection (vLOD) for the concentrations of STZ,sulfamethoxazole,sulfamethizole,sulfadiazine,sulfamerazine,sulfadimethoxine,sulfamonomethoxine,sulfameter,sulfamethoxypyridazine,and sulfachloropyridazine were 5,0.25,0.25,10,5,10,25,2.5,5,0.25,and 10 μg/kg,respectively.Scanner analysis in honey samples revealed good performance for detection of the 26 sulfonamides.Commercial honey samples were tested with the sensor and positive results were confirmed with high-performance liquid chromatography.The proposed strip sensor provides a convenient method for the rapid and reliable determination of sulfonamides pollutants in honey samples. 相似文献
9.
Floral nectar phenolics as biochemical markers for the botanical origin of heather honey 总被引:1,自引:0,他引:1
Federico Ferreres Paula Andrade Maria I. Gil Francisco A. Tomás-Barberán 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,202(1):40-44
In order to find out biochemical markers for the botanical origin of heather (Erica) honey, the phenolic metabolites present in heather floral nectar, collected from the honey-stomach of bees gathering nectar from these flowers, were analysed. The flavonoid fraction of nectar contained four main flavonoids. Two of them were quercetin and kaempferol 3-rhamnosides, and the other two were tentatively identified as myricetin 3-methyl ether and isorhamnetin 3-rhamnosides. Since the natural glycosides are hydrolysed by bee enzymes to render the corresponding aglycones, which are the metabolites detected in honey, acid hydrolysis of the nectar glycosides was achieved. The aglycones quercetin, myricetin 3-methyl ether, kaempferol and isorhamnetin were identified, as well as the gallic acid derivative ellagic acid. The analysis of Portuguese heather honey samples showed that ellagic acid was present in all the samples in significant amounts ranging between 100 g and 600 g per 100 g honey. The other nectar-derived flavonoids were also present, although some of them in very variable amounts. Ellagic acid and myricetin 3-methyl ether, which have not been detected in any of the monofloral honey samples investigated so far, with the only exception being a French honey sample of the botanically relatedCalluna (Ericaceae) which also contained ellagic acid, seem to be the most useful potential markers for the floral origin of heather honey. However, more detailed and extensive investigations are needed to prove the utility of these markers. 相似文献
10.
不同微生物发酵剂及木醋液在草炭发酵中应用效果研究 总被引:6,自引:0,他引:6
草炭与硬杂木锯末以2.6:1比例混匀后,接种不同微生物发酵剂和喷施500倍木醋液,在温室里容积为2.5m^3的发酵槽中进行对比试验,试验结果:喷施500倍木醋液比对照最高发酵温度高7℃,平均发酵温度高4℃;大于40℃以上中高发酵温度多7天;HA总比对照增加11.47%,HA游含量也略高于对照。在只接种微生物发酵剂的处理中,最高发酵温度是酵素菌56℃〉高温纤维分解菌55℃〉秸秆速腐剂54℃〉EM53℃〉对照46℃;在喷施木醋液条件下接种发酵剂,最高发酵温度是高温纤维分解菌57℃=酵素菌57℃〉速腐剂50℃〉EM48℃。HA总及HA游含量也是高温纤维分解菌+木醋液与酵素菌+木醋液两个处理明显高于对照及其他接种剂处理。 相似文献