luhongyun311全部評論(2條)
贊(19)
回復(fù)(0)
熱門問答
- 廣州數(shù)控980tdb運行宏程序怎么到這句就報警，請高手幫忙，謝謝！
2014-08-17 03:59:38
889
2
- 廣州數(shù)控980TDb如何讀取PLC監(jiān)控程序
- 想修換刀反鎖時間
2017-03-06 05:38:30
651
1
- 烘箱溫度控制高手請幫忙?。。?！
- 有聽說過一種通過控制加熱功率的百分比輸出來控制烘箱溫度的方法！請問是使用壽命儀表或者元件來實現(xiàn)的?。。?！求高手幫忙！或者有沒有其他方法通過控制加熱功率來實現(xiàn)烘箱的溫控??！... 有聽說過一種通過控制加熱功率的百分比輸出來控制烘箱溫度的方法！請問是使用壽命儀表或者元件來實現(xiàn)的！?。?！求高手幫忙！ 或者有沒有其他方法通過控制加熱功率來實現(xiàn)烘箱的溫控！?。。。。≌埜嬖V幫忙！ 展開
2016-02-15 21:10:22
426
1
- 大腸桿菌檢測的問題，請高手幫忙
- 如題，在大腸桿菌GB/T 4789.38 2008中，Z終的大腸桿菌數(shù)是根據(jù)LST肉湯陽性管數(shù)查MPN表得到的，那么后面的復(fù)發(fā)酵試驗和生化試驗是不是可以不用做的啊? 后面是不是就是為了驗證以上檢測的準(zhǔn)確性的呢？ 請高手賜教，不勝感激涕零
2010-05-10 10:10:32
607
1
- 請高手幫忙翻譯一下 3
- 2.2.1. Physical and physicochemical characterization The particle size distribution of the Ch-zeolite was determined using a laser diffraction equipment (CILASk 1064) and standard wet sieving (Mesh Tylerk series). Scanning electron mic... 2.2.1. Physical and physicochemical characterization The particle size distribution of the Ch-zeolite was determined using a laser diffraction equipment (CILASk 1064) and standard wet sieving (Mesh Tylerk series). Scanning electron microscopy (SEM-PHILIPSk XL20) was used for photomicrographs as well as to analyse the Ch-zeolite composition (Energy Dispersion X-ray， EDX). The sample was initially placed in a vacuum chamber for coating with a thin layer (few nanometers) of gold (Au). The specific surface area of the material was measured by the methylene blue technique and by nitrogen gas adsorption methods， with the latter also providing information about particle porosity. In the methylene blue adsorption method， aqueous solutions (50 ml) of methylene blue (100 mg l 1) were agitated using an orbital shaker (Marconik) for an hour at room temperature in the presence of different quantities of the Ch-zeolite (0.05–0.3 g). The suspensions were then allowed to settle for 23 h and the resulting supernatants were centrifuged at 5000 rpm before the analysis of the residual methylene blue concentration. Results obtained correspond to averaged values of three different experiments. The specific surface area was evaluated by the Langmuir model， assuming the formation， at high concentrations， of a dye monolayer and 1.08 nm2 molecule 1， for the cross-sectional area (Van den Hul and Lyklema， 1968). The Ch-zeolite specific surface area was evaluated by the nitrogen gas adsorption method， using automated equipment (Autosorb 1-Quantachrome Instrumentsk)， employing multipoint BET isotherm adsorption data fitting. Also from these data， the porosity of the material was evaluated through parameters such as volume of total pores (d < 206 nm)， surface area and volume of micropores (d < 2 nm; Micropore Analysis Method). Zeta potential measurements for the natural and ammonia loaded zeolite， as a function of medium pH， were determined using a Zeta Plusk equipment (Brookhaven Instruments). Suspensions (0.01% v/v) of the Ch-zeolite， previously sieved below 37 Am (400 Mesh Tylerk)， in a 10 3 mol l 1 solution of KNO3 were used and the medium pH was controlled with the addition of HNO3 (pH< 7) and KOH (pH>7)， separately. For the Ch-zeolite saturated with ammonia， suspensions of the material were prepared by the same procedure， except that the sample was loaded with 100 mg NH3–N l 1 of ammonia. 展開
2018-11-22 17:49:22
328
0
- 分貝疊加問題，請高手幫忙
- 有一種設(shè)備的噪音為3米處55分貝，如果五臺這種設(shè)備放在一起，那所產(chǎn)生的噪音是多大？求公式及原理？請詳細(xì)解答，會增加懸賞的，拜托了，高手們... 有一種設(shè)備的噪音為3米處55分貝，如果五臺這種設(shè)備放在一起，那所產(chǎn)生的噪音是多大？求公式及原理？請詳細(xì)解答，會增加懸賞的，拜托了，高手們 展開
2013-08-31 01:54:22
1088
2
- 西門子數(shù)控車802s對刀出現(xiàn) “存取不允許” 請高手幫忙解決一下
- 我在網(wǎng)上也查了一下 說是系統(tǒng)權(quán)限問題 好像是鎖上了 在機床上怎么能修改權(quán)限 如果把系統(tǒng)電池重裝下能行嗎 請高手指點
2017-11-24 18:07:41
1379
1
- 請高手幫忙翻譯翻譯啊，通順即可，完全用翻譯器的請繞道~謝謝~~
- Interim Report on Pressure Effect on Waxy-Crude Pipeline-Restart Conditions Investigated by a Model System Yield Phenomenon and Pipeline Restart. Yield stress is the threshold stress required to initiate ?ow of a viscoplastic ?... Interim Report on Pressure Effect on Waxy-Crude Pipeline-Restart Conditions Investigated by a Model System Yield Phenomenon and Pipeline Restart. Yield stress is the threshold stress required to initiate ?ow of a viscoplastic ? uid. Waxy crude-oil gels are viscoplastic in nature and exhibit time-dependent Bingham plastic ?ow behavior during restart under imposed constant pumping pressure. The yielding process of a gel is a complicated process， and different models have been proposed to explain this phenomenon. Wardhaugh and Boger (1991) defined yield stress as the “shear stress at which the gelled oil ceases to behave as a Hookean solid.” Chang et al. (1998) adopted a three-yield stress concept: elastic limit (which defines the onset of viscoelastic creep)， static (where fracture occurs)， and dynamic yield stress (which describes the broken down structure after yielding). Among these three， only the static yield stress is used to design the restart pump for initiation of flow after shut-in. Several types of apparatus and different techniques (direct and indirect) have been used for determining the yield stress. The results obtained and conclusions regarding their validity and usefulness differ widely. Setups used are capillary U-tubes， large pilot pipeline facilities， lab-scale model pipelines， controlled-stress or -shear rotational rheometry experiments (CSR). The capillary tube and pilot-scale pipeline measurement tech-niques have been criticized as being unsuitable for understanding the yielding behavior of statically cooled waxy crude oils because of nonlinear pressure distribution， pipe compressibility effects， porosity of wax structure， and contraction effects (Wardhaugh and Boger 1991). However， the authors added that an exception to their conclusion was the work by Ronningsen (1992)， where reasonable estimates of the yield stress as compared to model pipeline results were obtained with a constant stress rheometer. Recently， Lee et al. (2007) also reported the consistency between the concentric rheometer and a model pipeline system. In fact， model pipeline test is the most common laboratory method resorted to in gel strength measurement because of its geometrical resemblance to the real pipeline. In such tests， gel is formed under controlled conditions (cooling rate， aging temperature， etc.) and pressure is then slowly applied on one end of the gel until flow is observed. The gel strength (τ) is then calculated by: 公式1 展開
2012-05-03 00:39:39
459
2
- 機械制圖題目，請高手幫忙！不會勿擾
- 1、在圖樣中比例是指圖形與實物相應(yīng)要素的（?。┲??！ ?A)、大小之比 (B)、面積之比 (C)、線性之比 (D)、體積之比2、一張A0圖紙可以裁成（?。圓3圖紙?！ ?A)、三張 ... 1、在圖樣中比例是指圖形與實物相應(yīng)要素的（ ）之比。 (A)、大小之比 (B)、面積之比 (C)、線性之比 (D)、體積之比2、一張A0圖紙可以裁成（ ）張A3圖紙?！ ?A)、三張 (B)、四張 (C)、六張 (D)、八張 3、在圖樣上標(biāo)注垂直方向的尺寸時，尺寸數(shù)字應(yīng)注寫在尺寸線的左方中間位置且字頭朝（ ?。！ ?A)、上 (B)、下 (C)、左 (D)、右 4、在圖樣上標(biāo)注圓弧尺寸時起止符號用（ ）?！ ?A)、45°斜線 (B)、箭頭 (C)、圓點 (D)、× 5、在繪制機械圖時，通常采用的是（ ?。┩队胺ā！ ?A)、ZX (B)、正 (C)、斜 (D)、以上都可以 6、物體的側(cè)面投影是從物體的（ ）投影?！ ?A)、左面向右 (B)、右面向左 (C)、上面向下 (D)、前面向后 7、點的投影規(guī)律中高平齊是指（ ）之間 的投影關(guān)系?！ ?A)、V面和H面 (B)、V面和W面 (C)、H面和W面 8、在軸測投影圖的傾斜線上不能直接量取尺寸，只能在與軸測軸（ ）的對應(yīng)線上量取?！ ?A)、成一定角度的 (B)、相交 (C)、平行 (D)、不平行 9、水平線的（ ）投影反映線段的實長。 (A)、正面 (B)、水平 (C)、側(cè)面 (D)、以上都可以 10、側(cè)垂線的（ ?。┩队坝芯鄯e性?！ ?A)、正面 (B)、水平 (C)、側(cè)面 (D)、以上都可以 11、平面圖形為水平面時，它的（ ）面投影反映平面圖形的實形?！ ?A)、V (B)、H (C)、W (D)、以上都可以 12、用正垂面截切圓柱時，截平面與圓柱的軸線成（ ）度角時，它的側(cè)面投影是圓?！ ?A)、30 (B)、45 (C)、60 (D)、90 13、用正垂面截切圓錐，截交線為橢圓時，橢圓短軸的正面投影在（ ）。 (A)、軸線與截交線的交點 (B)、截交線的中點 (C)、任意位置 (D)、截交線的端點 14、如果在圓球正面投影兩軸線的交點處有一個點為可見點的正面投影，它的側(cè)面投影在（ ）。 (A)、兩軸線的交點 (B)、在垂直軸線的Z高點 (C)、在垂直軸線的Z低點 (D)、在水平軸線的Z右點 15、在圓球的水平投影上有一段斜線，此線段的正面和側(cè)面投影是（ ?。?。 (A)、一個點 (B)、一段直線 (C)、圓的一部分 (D)、橢圓的一部分 16、每張圖樣都必須畫出標(biāo)題欄，標(biāo)題欄應(yīng)位于圖紙的（ ?。??！ ?A)、左上方 (B)、左下方 (C)、右上方 (D)、右下方 17、不論采用何種比例，圖形中所標(biāo)注的尺寸數(shù)值必須是實物的（ ?。┏叽?。 (A)、實際 (B)、圖形上量得的 (C)、放大后的 (D)、縮小后的 18、若點A的坐標(biāo)值為（0、20、10）時，點A在（ ?。┥??！ ?A)、正面投影面 (B)、水平投影面 (C)、側(cè)面投影面 (D)、X軸 --------------------------------------------------------------------------------19、在圓錐上的點B，它的正面和水平投影均在圓錐的垂直軸線上，側(cè)面投影在圓錐的右面輪廓線上，則點B一定在圓錐的（ ）素線上?！ ?A)、Z前 (B)、Z后 (C)、Z左 (D)、Z右 20、如果點E和點F在正面投影面上是重影點，則它們的（ ）坐標(biāo)值相同?！ ?A)、X和Y (B)、X和Z (C)、Y和Z (D)、X、Y和Z 展開
2012-12-04 12:27:13
426
4
- 請高手幫忙翻譯化學(xué)名詞，急需~~~~
- 以下的技術(shù)指標(biāo)用語都是關(guān)于PVC顆粒的，請知道的幫忙準(zhǔn)確地翻譯~~~謝謝VICATPOINTHARDNESSTENSILESTRENGTHYIELDPOINTELONGATIONATBREAKFLEXURALMODULUSIMPACTSTRENGTHINFLAMMABILITYA... 以下的技術(shù)指標(biāo)用語都是關(guān)于PVC顆粒的，請知道的幫忙準(zhǔn)確地翻譯~~~謝謝 VICAT POINT HARDNESS TENSILE STRENGTH YIELD POINT ELONGATION AT BREAK FLEXURAL MODULUS IMPACT STRENGTH INFLAMMABILITY AV.A.P. IMPURITY PARTICLE NUMBER VOLATILES（INCL WATER） BULK DENSITY SIEVE RATIO “FISH EYE”NUMBER UNIT/400c㎡ RESIDUAL VCM PPM 展開
2007-03-13 04:50:47
505
3
- 關(guān)于液相色譜（HPLC）回收率，請高手幫忙！
- 1、為什么做液相色譜的時候要計算回收率？有什么意義？2、請幫忙舉一個計算回收率的例子，或者發(fā)一篇介紹回收率很詳細(xì)的文獻(xiàn)到我的郵箱，請注明你在百度的ID，我會把懸賞分提高到50，... 1、為什么做液相色譜的時候要計算回收率？有什么意義？ 2、請幫忙舉一個計算回收率的例子，或者發(fā)一篇介紹回收率很詳細(xì)的文獻(xiàn)到我的郵箱，請注明你在百度的ID，我會把懸賞分提高到50，多謝??！ 郵箱：putinfans@163.com 展開
2010-12-19 14:22:55
860
2
- 請高手高手高高手幫忙翻譯下面的設(shè)備名稱
- 請幫忙翻譯下：謝謝！斑點酶解系統(tǒng)自動斑點切取系統(tǒng)蛋白純化系統(tǒng)基因芯片掃描系統(tǒng)二維電泳梯度膠制備系統(tǒng)全自動電泳儀多通道懸液芯片系統(tǒng)體內(nèi)可見光成像系統(tǒng)如果您翻譯的十分準(zhǔn)確，我... 請幫忙翻譯下：謝謝！ 斑點酶解系統(tǒng) 自動斑點切取系統(tǒng) 蛋白純化系統(tǒng) 基因芯片掃描系統(tǒng) 二維電泳梯度膠制備系統(tǒng) 全自動電泳儀 多通道懸液芯片系統(tǒng) 體內(nèi)可見光成像系統(tǒng) 如果您翻譯的十分準(zhǔn)確，我將再加Z高分（好像是100分）。 我要英文，謝謝！ 展開
2009-07-21 06:02:17
773
6
- 請專家?guī)兔Ψg一下，謝謝！
- 粒度檢測方法與優(yōu)缺點比較 粉末粒度分布的測量方法經(jīng)過百余年的發(fā)展，據(jù)統(tǒng)計至少已經(jīng)發(fā)展了上百種，但隨著科技的發(fā)展，有些方法被逐步淘汰，有些方法得到了改進(jìn)和發(fā)展（如激光散射法、動態(tài)光散射等）， 并在生產(chǎn)、科研中得到了廣泛的應(yīng)用，現(xiàn)在普遍使用的測量... 粒度檢測方法與優(yōu)缺點比較 粉末粒度分布的測量方法經(jīng)過百余年的發(fā)展，據(jù)統(tǒng)計至少已經(jīng)發(fā)展了上百種，但隨著科技的發(fā)展，有些方法被逐步淘汰，有些方法得到了改進(jìn)和發(fā)展（如激光散射法、動態(tài)光散射等）， 并在生產(chǎn)、科研中得到了廣泛的應(yīng)用，現(xiàn)在普遍使用的測量方法有篩分法、顯微圖像法、光透沉降法、激光散射（衍射）法等幾種，下面簡單介紹幾種常用的粒度測量方法。 ▲ 篩分法 是一種具有很長歷史的粒度測定方法，篩分法粒度測量是利用一組篩孔大小不同的標(biāo)準(zhǔn)篩將粉末進(jìn)行篩分，然后對每個篩上樣品分別進(jìn)行稱重，進(jìn)而得到以質(zhì)量為量綱的粒度分布數(shù)據(jù)，并可由分布結(jié)果計算出如Dv50等其它參數(shù)。篩分滶要特點是測量成本低廉，操作簡單，但存在著如重復(fù)性差，測量時間較長，不能對5um以下的顆粒進(jìn)行測量等缺點。 ▲顯微圖像分析法 利用光學(xué)或電子顯微鏡及計算機圖像識別技術(shù)對顆粒粒度及粒度分布，顆粒形貌進(jìn)行測量，分析的方法。這種方法不僅能夠測量粒度分布而且能夠直接觀察到顆粒的形狀，是目前唯yi的一種可目視的直觀測試方法，這種特點也是其它粒度測量儀器所不具備。這種方法的優(yōu)點是直觀、簡便、費用低，缺點是由于取樣量很少，為使測量結(jié)果代表性，必須增加待測顆粒的個數(shù)（一般認(rèn)為測量顆粒的個數(shù)應(yīng)在1000個以上），這就相應(yīng)嗇了測量時間，及測試人員的工作強度，但由于能夠?qū)︻w粒形貌（如長徑比等）進(jìn)行測量，目前也有廣泛應(yīng)用。 ▲光透沉降法 沉降法粒度測試的理論基礎(chǔ)是斯托克司定律和比爾定律。前者給出顆粒沉降速度與粒徑的關(guān)系，后者闡明光透過率與粒徑重量的關(guān)系?？珊唵蔚拿枋鰹椋涸诔两狄褐?，有若干相同比重的顆粒，如果同一時刻，從同一位置開始下降，則不同直徑的顆粒到達(dá)測量區(qū)的時間是不同的，根據(jù)顆粒到達(dá)測量區(qū)的時間，及光強的強弱，就可以計算出顆粒的粒徑，及相應(yīng)粒徑的顆粒在顆粒群中占有的比例。采用此種原理的測量儀器有比較長的使用歷史，但隨著科技的發(fā)展和測量手段的進(jìn)步，此方法的缺點也日益突出，如測量時間長，重復(fù)性誤差大等。 ▲ 激光散射法 顆粒測量儀器是以富朗和菲衍射（Fraunhofer diffraction）和米氏散射（Mie scattering）為理論基礎(chǔ)。此理論可以簡單理解為沿直線傳播的平行激光束，在傳播過程中遇到顆粒的遮擋后，傳播方向發(fā)生了改變（即發(fā)生了衍射和散射現(xiàn)象），并且大顆粒使激光改變的角度小，小顆粒改變大。（實際上是由于顆粒的遮擋在無限遠(yuǎn)處形成了一個愛里斑，愛里斑87%的能量集中在ZX亮環(huán)，且顆粒直徑越大，ZX環(huán)越小，顆粒直徑越小ZX亮環(huán)越大）。如果能在不同角度上接收光能， 對于相應(yīng)的的角度，其光能是對應(yīng)直徑的顆粒集合發(fā)生衍射（散射）造成的，相應(yīng)其他角度上光能的強弱也就反應(yīng)了對應(yīng)直徑顆粒在整個顆粒集合中占有的比例。 ▲ 采用激光粒度測量儀器相對于光透沉降粒度測量儀器具有很多優(yōu)點： 1. 原理先進(jìn)，并且由于測試過程中沒有需要預(yù)先設(shè)定的參數(shù)（如樣品比重、介質(zhì)黏度、環(huán)境溫度等），及在測量過程中隨時改變的條件， 因此測量結(jié)果準(zhǔn)確、可靠。 2. 測量速度快，測試時間與樣品粒度分布無關(guān)，典型測試過程一般小于一分鐘； 3. 每次測試，多次對樣品進(jìn)行掃描，測試結(jié)果重復(fù)性好； 4. 進(jìn)樣方式種類多，可適用于各種類樣品。 展開
2016-03-07 05:37:01
674
1
- 英語高手幫忙翻譯段英文 謝謝！！
- In this paper， the degradation of an azo dye Orange G (OG) on nitrogen-doped TiO2 photocatalysts has been investigated under visible light and sunlight irradiation. Under visible light irradiation， the doped TiO2 nanocatalysts demonstrated ... In this paper， the degradation of an azo dye Orange G (OG) on nitrogen-doped TiO2 photocatalysts has been investigated under visible light and sunlight irradiation. Under visible light irradiation， the doped TiO2 nanocatalysts demonstrated higher activity than the commercial Dugussa P25 TiO2， allowing more ef?cient utilization of solar light， while under sunlight， P25 showed higher photocatalytic activity. According to the X-ray diffraction (XRD)， X-ray photoelectron spectroscopy (XPS) and UV–vis spectra analyses， it was found that both the nanosized anatase structure and the appearance of new absorption band in the visible region caused by nitrogen doping were responsible for the signi?cant enhancement of OG degradation under visible light. In addition， the photosensitized oxidation mechanism originated from OG itself was also considered contributing to the higher visible-light-induced degradation ef?ciency. The effect of the initial pH of the solution and the dosage of hydrogen peroxide under different light sources was also investigated. Under visible light and sunlight， the optimal solution pH was both 2.0， while the optimal dosage of H2O2 was 5.0 and 15.0 mmol/l， respectively. Azodyes， which are characterized by the presence of one or more azo bonds ( N N )， are among the most notorious widespread environmental pollutants associated with textile，cosmetic， food colorants， printing， and pharmaceutical indus-tries. Because of their non-degradability， toxicity， potential mutagenicity and carcinogenicity， wastewaters originating from these dyes production or application industries pose a major threat to the surrounding ecosystems and human beings’ health.[1–3].Environmental concerns and the need of meeting the strin-gent international standards for rejecting wastewaters has made the development of novel and cost-effective processes for the puri?cation of azo dyes ef?uents an issue of major technological importance. 展開
2011-05-06 19:00:45
584
2
- 高分請高手幫忙翻譯英文文獻(xiàn)資料（4）
- Whenliquidisheateditevaporates.Theevaporationprocessisdependentonpressure，temperatureandcompositionoftheliquidandgas.Gascanalsocondense.Inadditionthereisaconvectiveheattr... When liquid is heated it evaporates. The evaporation process is dependent on pressure， temperature and composition of the liquid and gas. Gas can also condense. In addition there is a convective heat transfer between the liquid and gas zone that must be considered. The surfaces in the gas zone also radiates from the shell to the liquid. During the blowdown process mass is usually evacuated from the gas zone， but also liquid might be released. The rate of release is dependent on density and pressure as well as the release area. As pressure and temperature change， the properties of all materials change. This has to be considered in a prediction of a blowdown process. The main purpose of a blowdown process is as earlier stated to maintain integrity of the equipment. The strength properties of the shell are the key factor on that matter. The strength is dependent on the inside pressure as well as the support forces. If the exposing forces produce stress that exceeds the ultimate tensile stress (UTS) in some regions， the integrity of the equipment is no longer maintained. In the design phase of a process plant， these aspects are crucial and must be included as a dimensional factor. For that reason prediction of the blowdown process is essential. Lately some new standards has been introduced to the industry on this matter [3] and [4]. VessFire [1] and [2] is a multi physics system designed for calculation of this kind of problems. It has been applied for some time in the oil and process industry on many projects. The system satisfies the requirements for predictions outlined in [3] and [4]. It includes all aspects described above including integrity of the shell. As part of the verification process some experiments where performed. Some of the experiments are presented here. EXPERIMENTAL STUDY The purpose of the experiments was to investigate the evaporation process and the heat transfer to the liquid and vapour. In a complex system it is important to reduce unknown parameters as far as possible. Exposure from a flame is difficult to control. Flux measurements are point values and not necessarily representative for the average exposure. In order to control the heat exposure it was decided to apply an electric heating system. The system and the verification of the system is described in [5]， [6] and [8]. The furnace was built inside a supporting tube. Figure 2 shows a general arrangement of the experimental outfit. A 0.05 mm stainless steel foil formed as a tube， 300 mm in diameter， generated the heat. The power supply was based on a 3-phase alternating current system giving 48 Volt output as maximum. The top exposure had a limit of 300 kW. The foil had a surface of about 1 m2， giving a heat flux up to 300 kW/m2. The power input could be continuously regulated from zero to maximum load. Each experiment was started from zero and brought up to the required load within a few seconds. After that the surface temperature of the heating foil was kept constant during the exposure period. Experiments with both dry objects as well as water filled object were performed. In this paper only water filled experiments are presented Figure 2 General arrangements drawing of the experimental furnace including the specimen and its support Figure 3 Illustration of the heating unit. The black part is copper conductors for the foil. The grey part is the heating foil exposing the specimen. The foil is equipped with thermo-elements all marked H， except H5 which is the temperature in a copper ring and H6 which is the temperature between the insulation and the supporting tube. 展開
2009-03-12 04:13:30
539
6
- 關(guān)于微生物學(xué)的一道題，請高手幫忙
- “直接挑取在平板上形成的單菌落就可以獲得微生物的純培養(yǎng)”這句話是錯的為什么？？？... “直接挑取在平板上形成的單菌落就可以獲得微生物的純培養(yǎng)” 這句話是錯的 為什么？？？ 展開
2010-03-15 12:16:40
732
5
- 請高手幫忙：如何查ISTP檢索號
- Exploring Sustained Competitive Advantage: The Effect of Organizational Culture on Firm Performance
2012-10-29 12:59:28
278
1
- 廣州數(shù)控 伺服電機 編碼器怎么調(diào)零
2017-11-25 12:46:23
1567
1
- 華中數(shù)控伺服驅(qū)動器A3報警怎么修
2012-03-16 11:42:53
2986
7
4月突出貢獻(xiàn)榜
推薦主頁
最新話題
滬公網(wǎng)安備 31011502008050號
參與評論
登錄后參與評論