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- 何愛云000 2010-10-09 00:00:00
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- wobingzhang 2010-10-10 00:00:00
- 不到冰糯，價格1000元之內(nèi)。A代表天然，不是等級。
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- 請各位大俠幫忙鑒定一下這個冰糯種A級翡翠。
2010-10-08 20:17:57
388
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- 冰糯種翡翠觀音吊墜市場價多少錢？
2016-08-09 03:01:57
378
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- 請哪位大師幫忙鑒定一下這是什么種的翡翠，價值多少呢?。?
2016-03-23 04:09:03
421
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- 請各位大蝦幫忙翻譯一下：
- Withmorethan6millionnewmeasurementchannelssoldlastyear，NationalInstrumentsisaworldwideleaderinvirtualinstrumentation.Engineershaveusedvirtualinstrumentationformorethan25y... With more than 6 million new measurement channels sold last year， National Instruments is a worldwide leader in virtual instrumentation. Engineers have used virtual instrumentation for more than 25 years to bring the power of flexible software and PC technology to test， control， and design applications making accurate analog and digital measurements from DC to 2.7 GHz. This document provides an excellent introduction to virtual instrumentation as well as additional resources for continued research. What is virtual instrumentation? With virtual instrumentation， software based on user requirements defines general-purpose measurement and control hardware functionality. Virtual instrumentation combines mainstream commercial technologies， such as the PC， with flexible software and a wide variety of measurement and control hardware， so engineers and scientists can create user-defined systems that meet their exact application needs. With virtual instrumentation， engineers and scientists reduce development time， design higher quality products， and lower their design costs. 展開
2007-05-22 09:38:51
477
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- 這個蘭花是什么品種？請養(yǎng)蘭高人幫忙鑒定一下!
- 養(yǎng)的蘭花開花了，但是不能確認是什么品種，花形看起來有點像“彩鳳”。請養(yǎng)蘭高手幫忙鑒定一下品種、種類和市場價格，如果能有詳細的解說和品評那就更感激了！謝謝各位！蘭花圖片鏈接... 養(yǎng)的蘭花開花了，但是不能確認是什么品種，花形看起來有點像“彩鳳”。請養(yǎng)蘭高手幫忙鑒定一下品種、種類和市場價格，如果能有詳細的解說和品評那就更感激了！謝謝各位！蘭花圖片鏈接如下： 還有圖片：https://gss0.baidu.com/7LsWdDW5_xN3otqbppnN2DJv/%D5%BD%CD%BD%CE%DE%C3%FB/pic/item/6f8957d39dc34dff572c84a3.jpg https://gss0.baidu.com/7LsWdDW5_xN3otqbppnN2DJv/%D5%BD%CD%BD%CE%DE%C3%FB/pic/item/4186eff9520dd20e4f4aeaa3.jpg https://gss0.baidu.com/7LsWdDW5_xN3otqbppnN2DJv/%D5%BD%CD%BD%CE%DE%C3%FB/pic/item/7374943fe9eb84eb9f3d62b4.jpg https://gss0.baidu.com/7LsWdDW5_xN3otqbppnN2DJv/%D5%BD%CD%BD%CE%DE%C3%FB/pic/item/86388b8a7d1b38b8a4c272b4.jpg 如果還需要提供什么圖片，請留言！謝謝各位！ 展開
2009-10-03 02:12:00
450
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- 尿檢結(jié)果請各位幫忙分析一下 急??！
- BLD +3 *10.0mg/1 KET +1 * 1.0mmo1/1
2009-03-27 11:59:34
367
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- 請幫忙分析一下這個開關(guān)電源的原理。
2015-12-09 14:20:33
362
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- a貨冰種翡翠玉鐲的價格是不是很貴
2018-04-17 15:36:26
451
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- 各位大神，麻煩幫忙分析一下這個tl494開關(guān)電源電路圖。
- 如圖，我弄不明白Ui是怎么輸入的，如果和輸出共地，又是怎么實現(xiàn)過流保護的？ 然后，3號腳那樣接輸入不就固定為5V了嗎，那兩個誤差放大器還怎么用？ 還望大神們指點。
2018-03-08 08:56:50
547
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- 冰中翡翠A級 滿綠 值1200萬美元嗎
2015-02-13 03:10:18
536
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- 請各位高手幫忙翻譯一下專有名詞: 針規(guī)， 推拉力計 不勝感激
2006-12-29 15:15:48
390
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- 請幫忙翻譯一下，拜托
- A new kind of TiO2 nanotube array/Ni(OH)2 (TiO2/Ni(OH)2) composite electrode with the storage ability of light energy was prepared by the deposition of Ni(OH)2 on the TiO2 nanotube array， which was synthesized by anodizing Ti foils in an HF... A new kind of TiO2 nanotube array/Ni(OH)2 (TiO2/Ni(OH)2) composite electrode with the storage ability of light energy was prepared by the deposition of Ni(OH)2 on the TiO2 nanotube array， which was synthesized by anodizing Ti foils in an HF aqueous solution. SEM and XRD results showed that Ni(OH)2 particles were well distributed on high density， well-ordered and uniform TiO2 nanotube arrays. The photoelectrochemical properties of the TiO2/Ni(OH)2 electrode were investigated in NaHCO3/NaOH buffer solution (pH 10) by means of UV–vis absorption spectra， cyclic voltammogram (CV) and photocurrent measurements. It was found that the TiO2/Ni(OH)2 electrode was highly sensitive to light and exhibited excellent photoelectrochromic properties. Upon UV irradiation， the photogenerated holes by TiO2 nanotube arrays can oxidize Ni(OH)2 to NiOOH， and thus the TiO2/Ni(OH)2 electrode can be photo-charged by light。1. Introduction Among many visible light photocatalysts， TiO2nanostructures have attracted much attention due to high photocatalytic activ-ity， nontoxicity， chemical stability and huge potential applications [1–6]. The TiO2 nanotube array is one of most attention-getting TiO2nanostructures because of large surface area and outstanding charge transport properties. TiO2nanotube arrays can be utilized in dye-sensitized solar cells[7–9]， photocatalysis and hydrogen gas sensing [10]. So far， a variety of methods have been attempted to prepare TiO2 nanotube arrays， such as hydrothermal synthe-sis[11]， Langmuir–Blodgett technique [12]， solution casting [13] and anodization technique[10，14]， etc. Among these methods， the anodization technique has many advantages of low cost， low tem-perature and easy to be scaled up to large-area preparation. Recently， anewkindof photo-functional systemwith theenergy storage ability has been developed by coupling TiO2 photosen-sitive electrode with energy storage materials. In Takahashi and Tatsuma’swork[15]，aTiO2/Ni(OH)2bilayer thinfilmwas suggested for the oxidative energy storage. In this case， a redox-activep-type semiconductor Ni(OH)2is coupled withn-type TiO2photocatalyst to formap–njunction，WhenTiO2is illuminatedby light， holesgen-erated at the junction are separated from excited electrons， trans-ported into the bulk of Ni(OH)2and oxidized Ni(OH)2to NiOOH. Therefore， the oxidative energy storage system was constructed 展開
2012-11-13 20:08:52
530
1
- 伺服電機在轉(zhuǎn)動時噪聲很大，停下來有擺動，請各位大俠幫忙，謝謝！
- 我這臺伺服電機是新的，剛從廠家的。... 我這臺伺服電機是新的，剛從廠家的。 展開
2012-09-23 10:07:50
606
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- 關(guān)于翡翠鑒定
- 翡翠的吸收光譜是不是固定為437nm？翡翠的結(jié)構(gòu)對其價值有何影響？... 翡翠的吸收光譜是不是固定為437nm？ 翡翠的結(jié)構(gòu)對其價值有何影響？ 展開
2007-08-15 22:50:41
608
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- 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
- 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)篩將粉末進行篩分，然后對每個篩上樣品分別進行稱重，進而得到以質(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校腥舾上嗤戎氐念w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測量區(qū)的時間是不同的，根據(jù)顆粒到達測量區(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，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，多次對樣品進行掃描，測試結(jié)果重復(fù)性好； 4. 進樣方式種類多，可適用于各種類樣品。 展開
2016-03-07 05:37:01
674
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- 請專家?guī)兔Ψ治鲆幌履虺Ｒ?guī)
- 患者信息：女 50歲 天津 南開區(qū) 病情描述(發(fā)病時間、主要癥狀等)： 白細胞 97.5↑ 紅細胞36.7↑ 上皮細胞 28.2 管型 0.53 白細胞(高倍視野) 17.6↑ 紅細胞(高倍視野)6.6↑ 上皮細胞 (高倍視野)5.1 管型 (低倍視野) 0.53 病理管型0.53 結(jié)晶數(shù)量0 小圓... 患者信息：女 50歲 天津 南開區(qū) 病情描述(發(fā)病時間、主要癥狀等)： 白細胞 97.5↑ 紅細胞36.7↑ 上皮細胞 28.2 管型 0.53 白細胞(高倍視野) 17.6↑ 紅細胞(高倍視野)6.6↑ 上皮細胞 (高倍視野)5.1 管型 (低倍視野) 0.53 病理管型0.53 結(jié)晶數(shù)量0 小圓上皮細胞數(shù)量 1.7 類酵母細胞數(shù)量0 尿膽原 Normal 膽紅素 NEG 酮體NEG 隱血NEG 蛋白質(zhì)NEG 亞硝酸鹽NEG 白細胞酯酶+- Ca15 葡萄糖NEG 比重1.020 PH酸堿度 6.5 維生素C 0 微白蛋白NEG 展開
2012-03-12 14:56:37
399
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- 請專家?guī)兔﹁b定一下這石頭有磁性是塊什么石頭
2017-05-06 02:19:06
326
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- 有關(guān)路由器的安裝，請各位大俠指點/
- 我買了一個路由器不知怎么安裝，請問大俠們要怎么設(shè)置，
2006-09-17 02:12:15
554
2
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