全部評(píng)論(3條)
-
- 835148 2013-03-17 00:00:00
- 市場(chǎng)價(jià)格？你是個(gè)老財(cái)迷嗎？
-
贊(19)
回復(fù)(0)
-
- YLQ_ing 2013-03-03 00:00:00
- 較大的隕石在隕落過程中飛行，由于受到高溫、高壓的氣流的沖擊，會(huì)在半空發(fā)生爆
-
贊(18)回復(fù)(0)
-
- 風(fēng)雪白長(zhǎng)山 2013-03-17 00:00:00
- 鑒定一塊樣品是否為隕石，可以從以下幾方面考慮： 1．外表熔殼：隕石在隕落地面以前要穿越稠密的大氣層，隕石在降落過程中與大氣發(fā)生磨擦產(chǎn)生高溫，使其表面發(fā)生熔融而形成一層薄薄的熔殼。因此，新降落的隕石表面都有一層黑色的熔殼，厚度約為1毫米。 2．表面氣?。毫硗?，由于隕石與大氣流之間的相互作用，隕石表面還會(huì)留下許多氣印，就象手指按下的手印。 3．內(nèi)部金屬：鐵隕石和石鐵隕石內(nèi)部是有金屬鐵組成，這些鐵的鎳含量很高（5－10％）。球粒隕石內(nèi)部也有金屬顆粒，在新鮮斷裂面上能看到細(xì)小的金屬顆粒。 4．磁性：正因?yàn)榇蠖鄶?shù)隕石含有鐵，所以95％的隕石都能被磁鐵吸住。 5．球粒：大部分隕石是球粒隕石（占總數(shù)的90％），這些隕石中有大量毫米大小的硅酸鹽球體，稱作球粒。在球粒隕石的新鮮斷裂面上能看到圓形的球粒。 6．比重：鐵隕石的比重為8克/cm3，遠(yuǎn)遠(yuǎn)大于地球上一般巖石的比重。球粒隕石由于含有少量金屬，其比重也較重。 要想真正掌握并非易事。diyi步“眼觀”Z為重要。因?yàn)闂l件所限，我們不可能將每一塊石頭都做切面，或者用電子探針檢測(cè)，98%以上的待鑒物品是在目測(cè)的過程中來(lái)確定其是否有必要繼續(xù)檢測(cè)的。 這樣看也不確定，如果你真對(duì)這個(gè)感興趣，Z好拿到當(dāng)?shù)赜嘘P(guān)檢驗(yàn)所檢測(cè)。 隕石價(jià)格也根據(jù)稀少程度、元素含量等的不同而異。便宜的有幾十元/克，而月亮隕石、橄欖石隕石、鐵隕石等目前的價(jià)格則達(dá)到上萬(wàn)元/克。有的隕石高達(dá)上萬(wàn)元，而便宜的甚至只要二三十元。 這個(gè)得等你的石頭檢驗(yàn)結(jié)果才能知道了。 如果你覺得答案合適，請(qǐng)選為Z佳答案謝謝。
-
贊(7)回復(fù)(0)
登錄或新用戶注冊(cè)
- 微信登錄
- 密碼登錄
- 短信登錄
請(qǐng)用手機(jī)微信掃描下方二維碼
快速登錄或注冊(cè)新賬號(hào)
微信掃碼，手機(jī)電腦聯(lián)動(dòng)
注冊(cè)登錄即表示同意《儀器網(wǎng)服務(wù)條款》和《隱私協(xié)議》
熱門問答
- 請(qǐng)幫忙鑒別，是什么隕石嗎？直徑4cm左右，球形石m=110g。
2013-03-02 11:43:04
580
3
- 這是隕石嗎？？有什么方法鑒別
2013-10-23 02:42:12
416
4
- 直徑4cm，高6cm的透明石英坩堝多少錢？
2012-03-14 01:04:06
239
2
- 如何鑒別2014火星隕石的真?zhèn)?
2016-01-06 23:59:10
453
2
- 隕石是什么？
2011-04-21 18:10:27
310
2
- 隕石值錢嗎？
- 好幾十年的，大概兩三頓重
2013-08-04 13:27:50
416
2
- 請(qǐng)指教三菱plc梯形圖中M是什么意思
2016-11-14 00:39:40
1328
2
- 隕石要怎樣才能鑒定是隕石，它值錢嗎？
2012-11-22 15:55:10
286
1
- 天然琥珀蜜蠟原石該怎么鑒別真假？
2016-06-23 16:01:15
561
3
- 請(qǐng)幫忙名詞解釋溶劑殘留量
- 小弟期末考試要考，跪謝?。。。。。。。。。。~~~
2010-05-24 14:18:34
429
1
- 請(qǐng)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
- 烘箱溫度控制高手請(qǐng)幫忙?。。?！
- 有聽說過一種通過控制加熱功率的百分比輸出來(lái)控制烘箱溫度的方法！請(qǐng)問是使用壽命儀表或者元件來(lái)實(shí)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(lái)實(shí)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(lái)控制烘箱溫度的方法！請(qǐng)問是使用壽命儀表或者元件來(lái)實(shí)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(lái)實(shí)現(xiàn)烘箱的溫控?。。。。。≌?qǐng)告訴幫忙！ 展開
2016-02-15 21:10:22
426
1
- 有機(jī)硅球形樹脂粉是什么？
2016-02-25 23:34:36
414
1
- 翡翠原石的鑒別 解析如何科學(xué)鑒定真假翡翠原石的基本方法
2016-05-09 08:28:17
538
1
- 大腸桿菌檢測(cè)的問題，請(qǐng)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(yáng)性管數(shù)查MPN表得到的，那么后面的復(fù)發(fā)酵試驗(yàn)和生化試驗(yàn)是不是可以不用做的啊? 后面是不是就是為了驗(yàn)證以上檢測(cè)的準(zhǔn)確性的呢？ 請(qǐng)高手賜教，不勝感激涕零
2010-05-10 10:10:32
609
1
- 請(qǐng)幫忙整理一些化學(xué)資料
- 我需要整個(gè)初中所要用到的化學(xué)資料（ZD即可、因?yàn)槲覍W(xué)的還可以所以化學(xué)方程式的話只要晦澀少出現(xiàn)但是歷史上考到的、其他拜托了） Z好是考過的而寫還沒有把復(fù)習(xí)資料的人給一些ZD（如果嫌打上來(lái)麻煩的話弄點(diǎn)精要即可） 還需要一些經(jīng)典題目（給網(wǎng)站也... 我需要整個(gè)初中所要用到的化學(xué)資料（ZD即可、因?yàn)槲覍W(xué)的還可以所以化學(xué)方程式的話只要晦澀少出現(xiàn)但是歷史上考到的、其他拜托了） Z好是考過的而寫還沒有把復(fù)習(xí)資料的人給一些ZD（如果嫌打上來(lái)麻煩的話弄點(diǎn)精要即可） 還需要一些經(jīng)典題目（給網(wǎng)站也可以） 如果可以的話還需要高中高一年級(jí)所需要的一些知識(shí)點(diǎn)、大概就可以了（我差不多混個(gè)眼熟）以及一些很重要的高考必考的知識(shí)點(diǎn)。（MS麻煩到很多了） 但是真的拜托了 這些很重要啊 能不能再推薦一些有很好的試題的網(wǎng)站。 【抱歉、麻煩了】 【好的話加分】 展開
2010-04-12 06:58:07
510
1
- 請(qǐng)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
3
- 請(qǐng)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
330
0
4月突出貢獻(xiàn)榜
推薦主頁(yè)
最新話題
滬公網(wǎng)安備 31011502008050號(hào)
參與評(píng)論
登錄后參與評(píng)論