In this study, the stem segments of new shoot with axillary buds of well - growth tetraploid black locust trees were used as explants. the effects of different basic mediums, different hormone kinds and their concentrations ratios, different sucrose concentrations on calli induction, buds differentiation and rooting in the process of establishment of high frequency regeneration system of tetraploid black locust were studied. on the base of high frequency regeneration system, the effects of various factors on transformation efficiency of badh mediated by agrobacterium tumefaciens were discussed in the light of gus histochemical assays
本實驗首先以生長良好的四倍體刺槐優株上當年生新梢的帶腋芽莖段為外植體,研究了在四倍體刺槐高頻再生體系的建立過程中不同基本培養基、不同激素濃
度及其配比、不同蔗糖濃
度對愈傷組織的誘導、芽的分化及生根的影響;然後在得到高頻再生體系的基礎上,通過農
桿菌介導法轉化甜菜堿醛脫氫酶( badh )基因,以gus染色組織分析為依據探討了影響轉化效率的各種因素,建立了高效、可重復的基因轉化體系,為四倍體刺槐目的基因的導入打下了基礎。
Seed culture conditions of bacillus licheniformis ts - 01 were firstly investigated. the results showed that the optimal growth temperature was 40 c ; the suitable seed culture medium was beef extract soya peptone medium ; the optimal initial ph was 7. 5 ; the optimal seed culture time was 13h ~ 14h
首先對地衣芽孢
桿菌ts - 01的種子培養條件進行了研究,得到的結果為:最適生長溫
度為40 ;較適合的種子培養基為牛肉膏大豆蛋白腖培養基;最適初始ph值為7 . 5 ;種齡為13h 14h 。
Design of half - through steel pipe bowstring concrete arch bridge of long - span, and knowledges to it
大跨
度中承式鋼管系
桿混凝土拱橋設計和體會
The calculation modes of the coefficient of shrinkage and creep of the bulgy core concrete in steel tube are discussed. based on a few reasonable hypotheses and the stress - strain relation of concrete acquired by the " adjusting valid modulus depending on load time " method, a compact formula is reasoned out, which is applied to calculate the equivalent elastic modulus of the bulgy core concrete considering the affection of shrinkage and creep. so, the analysis of the affection on cfst arch bridge by shrinkage and creep can be progressed by pole - girder fem, further more, the analysis precision is quite high
本文還對核心膨脹混凝土特殊的收縮、徐變系數計算模式展開了探討,在合理的假設前提下,採用「齡期調整的有效模量法」得到的混凝土的本構關系,推導出鋼管內核心混凝土在考慮徐變影響后的等效彈性模量計算公式,並以此為基礎採用
桿系有限元方法來對鋼管混凝土拱橋進行較高精
度的收縮徐變分析。
Laboratory glassware. solid - stem calorimeter thermometers
實驗室用玻璃器皿.熱量
桿式溫
度計
Vertical elements carry sufficient load through cantilever action to produce cantilever deflections equal to arch deflections.
垂直
桿件則借懸臂作用產生和拱撓
度相等的懸臂撓
度,來承擔足夠的荷載。
The results also revealed that it was a reasonable choice to use carbenicillin as the antibiotics of inhibiting growth of remnant agrobacterium after co - culture, and when hygromycin was used as the selective agent, continuous selection at low concentrations ( 50 ~ 150mg / l ) produced the highest numbers of transgenic plants without escapes
試驗表明,在農
桿菌介導高羊茅遺傳轉化中,抑菌劑宜選用梭節青霉素;以潮黴素作為選擇劑時,採用低濃
度( 50一15om留l )連續篩選的方式比較合適,在該方式下,獲得的轉基因植株較多。
This twin screw extruder has the feature of one - side circumgyrate , it ' s an ideal equipment for the small - scale factory who produce powder
該擠出機是同向高速旋轉雙螺
桿結構,是用於多種組份物料經一定的溫
度在熱狀態下達到最佳的理想效果,適應小型企業生產粉末的理想設備。
The degree of ultrastructural changes of rhabdom during light and dark adaptation of compound eye had something to do with the intensity and wavelength of environmental light in m. nipponense
線粒體為光感受膜的合成和降解過程提供能量。日本沼蝦復眼感
桿束明、暗適應時結構變化程
度與外界光強
度和光波長
度有關。
A small extension curtain rod is an excellent support rod for plants. the length can continually be adjusted without disturbing the plants
一個小的可以伸長的窗簾
桿是特別好的攀援植物種植
桿。它的長
度可隨著植物的生長而連續地調整,對植物則沒有干擾。
Petroleum industry. detachable swivel mounted graduated weight for steel tape dipsticks
石油工業.鋼帶量
桿用帶球頭關節的活動刻
度沉壓體
This drilling adopts crank connecting link and walking beam percussion mechanism, which make the drilling possess two percussive functions, normal drilling takes connecting link impact as main mode, when encountering special situation and the connecting link impact can not drill, it can transform into hoisting impact, the stroke length can be modulated, it realizes automatic percussive drilling due to continuous operating of connecting link percussive mechanism, these can enhance drilling efficiency and relieve labor intensity ; it adopts pumping reverse circulation to drain slag, which not only resolves the drilling difficulty in special stratum such as pebble and gravel stratum and hard stratum, but also resolves the problem that the percussive drill ' s efficiency is low ; it adopts spur gear differential mechanism as double cylinders lazy tongs of main hoist, which not only ensures the balance state of drilling tool, but also reduces the mechanical design, and reduces the cost ; the bottom plate traveling motion of this drilling machine adopts walking type ; the drilling tower adopts hydraulic pressure uprising, and reduces the assistant operating time
該鉆機採用曲柄連
桿、游梁式沖擊機構,使鉆機具有兩種沖擊功能;正常鉆進以連
桿沖擊為主,遇到特殊情況,用連
桿沖擊不能鉆進時,可轉為卷揚沖擊,沖程可調,因連
桿沖擊機構連續工作,所以實現了自動沖擊鉆進,可提高鉆進效率,減輕勞動強
度;採用泵吸反循環的方式排渣,既能有效解決卵礫石地層、堅硬地層等特殊地層鉆進的困難,又很好地解決了沖擊鉆機效率低下的問題;採用直齒圓柱齒輪差速機構作為主卷揚的雙筒同步機構,既保證了鉆具處于平衡狀態,又大大簡化了該機構設計,降低了成本;該鉆機底盤行走移位採用步履式;鉆塔採用液壓起立,減少了輔助作業時間。
Total length flexes from 78cm to 130cm, the t shape pole is fixed with two extrusive slots respectively. the middle umbrella gear is connected with the pole. turn the mop pole to move the rail beside gear through the umbrella gear function
:總長
度可由78公分伸縮拉長到130公分, 「 t 」形拖把
桿上橫
桿兩端分別有2個突出的卡槽中間一組傘形輪與拖把
桿本體連接固定,轉動拖把
桿通過傘形輪的作用「 t 」形拖把
桿上輪兩端的橫
桿即跟著傳動。
A team of mathematicians were required to measure the height of a flagpole
有人要求一隊數學家去測量一根旗
桿的高
度。
Marine light - weright three fulcrum bar graduator
船用輕型三
桿分
度儀
Dualdrive gearbox : drp worm gear unit : standard precision
蝸輪蝸
桿減速機:標準精
度n
Accuracy of double enveloping worm gearing with straight line generatrix
直廓環面蝸
桿蝸輪精
度
Control of discharge - sand gate discharge - sand gate adopts electro - hydraulic handspike ; it uses displacement transducer to measure opening of sluice gate ; when opening of displacement transducer is smaller than set point, the electro - hydraulic handspike will open this gate ; when opening of displacement transducer is larger than set point, the electro - hydraulic handspike will close the gate
卸砂門採用電液推桿,由位移傳感器檢測砂門的開度,當位移傳感器檢測的開度小於控制系統的給定值時,電液推桿工作將門開大,當位移傳感器檢測的開度大於控制系統的給定值時,電液推桿工作將門關小。