It is difficult to select the lactic acid high-producing strain by observing the color change zone because of spreading grow along the solid medium of Rhizopus oryzae. A serious of methods for selection and breeding of L-lactic acid high-producing mutant were developed.
米根霉在固体平板上生成的乳酸会使培养基中加入的pH指示剂变色，在菌落周围呈现出变色圈，但由于丝状真菌米根霉在固体培养基表面蔓延生长的特性，使得无法得到单菌落，进而无法通过观察变色圈与菌落直径之比来比较出各菌株产酸能力的高低。
The different processes in resistance selection between normal strain and mutant strain were studied.
并对甜菜夜蛾正常体和蛹黑型突变体的抗性选育过程进行了比较分析。
But natural selection is a powerful force, and if the spread of the disease means they have to be used widely, a resistant strain of the virus could easily evolve.
但是自然选择是一种强大的力量，而如果疾病的传播意味着这些药物将被广泛使用的话，一种具有抗药性的病毒毒株可能将轻易地进化出来。
Cyh-R was selected with no insecticide and normal bred, named ZS strain. The toxicity of the cyhalothrin was tested in generations of different resistant strains every twice after selection with topical application bioassay, to compare the difference with strain no-selected.
用喷雾法分别喷洒溴氰菊酯和甲基嘧啶磷于氯氟氰菊酯高抗药性家蝇品系，进行进一步的抗性选育，分别命名为中溴、中甲，同时自然衰退法得到中衰品系。
After treatment with ethyl methane sulfonate and selection, the strain Saccharomyces cerevisiae BEZ112 was obtained from Saccharomyces cerevisiae FB for beer brewage production.
以啤酒酿造生产菌株啤酒酵母FB作为出发菌株，用甲基磺酸乙酯诱变，经分离筛选得到一株优良的啤酒酵母菌株BEZ112。
Spodoptera exigua susceptible strain was also obtained by single mating selection.
本实验还采用单对交配的方法对SEW和SEM进行了敏感性筛选。
To know the effect of long term selection and different social environment on the behavior of Taiwan Country Chicken during rearing period, chickens used in this study were long time selected L2 strain of Taiwan Country Chicken for egg production, which were further selected based on high and low utilization of perch to reproduce L2H and L2L groups of chicken, to compare with a long term selected B strain for meat production.
本试验为了解遗传及不同社会环境对台湾土鸡栖息行为的影响，使用同源但分别长期选拔产蛋与产肉性能的台湾土鸡L2与B品系，且依亲代使用栖架高低情形，再选育出L2H与L2L两品系。
And the manufacture technology of special shaped stiffened thin wall shell is investigated systemically in practice and theory. According to the special shape and operate requirements of the torpedo, the structure and moulding process of the torpedo shell are established, in which the body and overlay block with grooves are moulded by fiber winding, and close moulding respectively with the adhesive by limited stop compression. In the light of the selection of raw material system, composite system with outstanding performance are defined, based on which the mechanical properties are tested., with the overall consideration of structural characters and design demands, the main factors which may have effects on the strength and stability (including stiffness section dimension, stiffeners space, skin thickness and skin lay angle) is optimized one by one for the structure design parameters on the base of the FEM model of skin, stiffness and layover block by FEM..As a result, the prototype with 1:1 proportion and its structure and lay optimization design are completed. The moulding technology for polyurethane foam moulding the stiffened shell is obtained in terms of the design, manufacture moulding, experimental mould and tooling. Furthermore, the prototype is experimented the hydrostatic test and provides the stress and strain results.
依据在研产品特殊的外型结构和使用要求，确定了该型号水雷复合材料壳体的具体结构形式和复合成型工艺路线，即由纤维缠绕工艺成型主体异形件，闭模成型带通槽外贴块，用限位加压工装实现粘接的工艺路线；通过对原材料体系的筛选，确定了综合性能较好的复合材料体系，以此为基础进行了力学性能测试；运用有限元方法，建立了蒙皮、筋条和外贴块的分析模型，综合考虑结构特点和设计要求，对影响结构强度与稳定性的主要因素(包括筋截面尺寸、筋间距、蒙皮厚度、蒙皮铺层角度)分别进行了结构设计参数的优选，最终完成了复合材料异形耐外压壳体1：1样件和缩比实验件结构及铺层优化设计；完成了聚氨酯泡沫胎成型内置加筋壳体的成型工艺技术研究；对缩比件进行外压性能测试，并给出了应力、应变测试结果。
In the present study, the homozygous strains of different gender isolated from fluconazole treatment were subjected for mutagenesis by UV radiation for the selection of auxotrophic mutant and the killing curve of each strain was measured in the same time for the determination of ploidy.
本研究利用二倍体和单倍体染色体的不同，照射紫外线后存活率不同，可初步判别a type菌株的倍数体。
Selection of Producing Lactobacillin Strains of Lactic Acid Bacteria and Its Applications in Meat Products and Pepper Fermentation; 2. A novel lactobacillin-producing strain was screened and isolated from pickle samples.
采用这一筛选模型，经过反复分离筛选，得到一株对多种革兰氏阳性和革兰氏阴性指示菌具有广谱抑菌活性且对绿脓杆菌具有较强抑菌活力的乳酸菌素产生菌，菌株编号HF08。
So not suitable for kinds of fish. Age 4 to age 6 goldfish Although there is still the ability to reproduce but goldfish reach the age of 4 or more the species often characterized by signs of a recession or the body color degradation it is not the best kinds of fish selection. 2 to 3 age goldfish and growth had been formed with the strain characteristics of the best period 2 to 3 years old goldfish goldfish can be said that the prime of life stage species with distinctive characteristics growth had been formed with strong genetic stability is also the best of kinds of fish selection.
所以，并不适合做种鱼。4龄至6龄金鱼虽然还有繁衍后代的能力，但当金鱼到达4龄以上时，该品种特征往往出现衰退迹象，或是体色出现退化，所以并非最佳种鱼选。2至3龄金鱼，成长已经定型，具备该品种特征的最佳时期，2至3龄金鱼可以说是金鱼壮年阶段，品种特征明显，成长已经定型，具有较强基因稳定性，也是最佳的种鱼选。
Part Two: 3-D Finite Element Method Study on Maxillary Protraction Objective: To explore the change rule of stress、strain and displacement of craniofacial complex against different strength and direction of maxillary protraction, so as to provide the scientific basis for the selection of force system in clinical treatment.
第二部分上颌前牵引的三维有限元研究目的：探讨不同大小和方向的前牵引力对整个颅面复合体的应力、应变和位移变化规律，以达到为临床力系统的选择提供科学依据的目的。
The highest enzyme producer alkalophilic Bacillus sp SHY8-1 among the inductive strains was mutagenized several times, by adding enzyme production repression aegents into screen medium, combined with natural seperation and pressure selection, finally a CMCase-hyperproductive mutant SHY8-1-25 (partitally resistant to catabolite) was obtained, with the yield of CMCase raised to 13-16u/ml, maximally reached 18-20u/ml, while its parent strain 0.654u/ml.
对诱导型产酶菌-嗜碱芽孢杆菌SHY8-1进行了多次诱变改良，采用添加产酶阻遏剂的平板作为筛子，结合反复的自然分离、压力选择，最终成功地获得了高产变异株SHY8-1-25(已部分解除分解代谢阻遏)，产酶量由0.654u/ml提高到13-16u/ml，最高达到18-20u/ml，讨论了诱变机理策略，考察了碳、氮源等对产酶的影响，对培养基和摇瓶培养条件进行了优化。
It introduces high-strain test method is a completeness means in engineering test, researches several aspects should be good in high-strain present test from hammering facility? erection of hammer tool? erection of sensor and selection of pile cushion to ensure good waveform.
阐述了高应变检测技术是工程检测中一种完整性手段，从锤击设备、锤击装置安装、传感器安装、试桩桩垫的选用等方面，探讨了高应变现场测试时应做好的工作，以确保波形质量较好。
Recent research on the selection and optimization of fermentation condition of bacterial cellulose strain, and the application of bacterial cellulose on such aspects as food, medicine, advanced stereo set vibration membrane, papermaking and adhesive-bonded fabric were introduced in this paper.
简要介绍了细菌纤维素菌种选育、发酵条件优化，以及细菌纤维素在食品、医药、高级音响设备振动膜、造纸与无纺织物等方面应用研究的近况。
Considering both the accuracy and the efficiency, the point quadrature based on the average strain of Delaunay triangle is a better selection, though its convergence and accuracy are a little lower than the partition of unity quadrature method.
采用单位分解积分方案，其计算精度和收敛性均好于基于平均应变的点积分方案，但综合计算精度和计算效率考虑，则基于平均应变的点积分方案较为理想。
25 strains of Flammulina velutipes were collected at home and abroad. An optimal strain FV_ (8812) for submerged culture was obtained by shaking flask culture selection. Its optimal fermentation medium and conditions were obtained through different shaking culture experiments.
从国内外收集金针菇菌株25株，经摇瓶初筛、复筛，获得1株适应深层培养的高产优质菌株FV（8812）。
Studies on Mutation and Selection of Pectinase Production Strain Aspergillus awamori Nakazawa F_ (77-101) and Certain Properties of Its Pectinase
果胶酶产生菌泡盛曲霉F（77-101）的选育和酶特性的研究
Studies on Selection of the Aureomycin Producing Strain F-303 and Its Fermentative Characteristics
金霉素产生菌F-303的选育及发酵特性
Studies on the second nitrogenase of Azotobacter 1. the selection and identification of strain
自生固氮菌第二固氮酶的研究&Ⅰ.菌种的分离和鉴定