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31.
给出了内蒙古段黄河水平中总α,总β,^90Sr,^137Cs,^40K,^3H,^210Pb,^210Po,^238U,^232Th、^226Ra放射性水平,结果基本为正常水平,找出了污染源,为内蒙古段黄河水中放射性监督监测建立了全面的背景材料。 相似文献
32.
Yusai Ito Naoki Sugimoto Takumi Akiyama Takeshi Yamazaki Kenichi Tanamoto 《Tetrahedron letters》2009,50(28):4084-11715
Cepaic acid was isolated as a novel xanthylium yellow pigment from the dried outer scales of the yellow onion Allium cepa Linne. Its structure was elucidated on the basis of ESI-MS and 2D NMR spectroscopy as a 9-carboxy-1,3,6,8-tetrahydroxyxanthylium, which suggests that cepaic acid and other yellow pigments in the dried outer skin of onion were formed by the nucleophilic reaction of phloroglucinol derived from quercetin, a flavonol in onion scales, by autoxidation to glyoxylic acid. To our knowledge, this is the first report of such a pigment in yellow onion. 相似文献
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34.
西气东输工程中卫黄河穿越隧道长1197.77m,高4.3m,宽5.6m。隧道入口高于黄河水位28m,出口高于黄河水位45m。隧道顶板高程为1130m。位于黄河水下100m。隧道场地围岩为寒武系磨盘井组灰绿色、银灰色浅变质中厚层细粒长石石英砂岩、千枚状板岩、绢云母化千枚岩。围岩为弱风化Ⅲ~Ⅳ类岩石。透水率为4~67Lu,纵波波速为500~3300m.s-1。BQ为300~400。变形模量为6.11~9.22GPa。泊松比(μ)0.14~0.24。内摩擦角(ψ)为42.1°~44.7°。地下水为基岩裂隙水。含水层为寒武系浅变质岩,受大气降水渗入补给,单井涌水量为1.0~50m3.d-1。隧道轴线穿越区岩体较完整—较破碎,未有全新活动断层。隧道位置选择和开挖深度设计是可行的。施工和长期运营是安全的。 相似文献
35.
由地质作用影响形成的易出险堤段称为地质险段 ,主要包括活断层作用影响形成的堤基易渗漏段、强地震高发区段和地基稳定性差段等。构造节点是识别地质险段的重要的河流地貌标志之一。根据成因 ,本文将黄河下游的地质险段分为三类 ,即新构造险段、沉降险段、断裂复活险段。针对黄河下游堤防地质特征 ,圈定出东坝头、大刘屯—董口黄河南岸和路那里—十里堡黄河南岸地质险段 ,提出了治理的有关措施 相似文献
36.
《Comptes Rendus Chimie》2015,18(10):1152-1160
In this study, the optimization and implementation of a homogeneous photo-Fenton process for the decolorization and mineralization of a wastewater containing highly concentrated yellow 5 (E102) dye, resulting from an industry placed in the suburbs of Medellin (Colombia), is presented. Response surface methodology was applied as a tool for the optimization of operational conditions such as initial dyestuff concentration, H2O2 concentration, and UV-radiation power (number of lamps). The decolorization, degradation and mineralization efficiencies were used as response variables. The following conditions were found to be optimal for decolorization and mineralization of yellow 5: UV radiation of 365 nm (4 W, one lamp), dye concentration of 200 mg/L, Fe2+ concentration of 1.0 mM, H2O2 concentration of 1.75 mL/L, treatment time of 180 min, Fe2+ concentration of 1 mM and pH = 3. Under these conditions (180 min), the photo-Fenton process allowed us to reach ca. 100% of color dye degradation, 99% of COD degradation, and 85% of mineralization (TOC). The scavenging effect of the Cl– anion on the photodegradation process was also confirmed. 相似文献
37.
Adsorption of Metanil Yellow Azoic Dye from Aqueous Solution onto Mg‐Fe‐NO3 Layered Double Hydroxide
Dr. Kamellia Nejati Zolfaghar Rezvani Mahsa Mansurfar Abolfazl Mirzaee Mehrdad Mahkam 《无机化学与普通化学杂志》2011,637(11):1573-1579
We report the preparation and characterization of a layered double hydroxide (LDH) adsorbent for azoic dye, metanil yellow (yellow GX; YGX) removal. The nanoparticles of Mg‐Fe‐LDH‐NO3 adsorbent were prepared with Mg/Fe molar ratio of 3:1 by a hydrothermal process and coprecipitation method at pH 9.5 and were characterized by X‐ray powder diffraction (XRPD), thermal gravimetric analysis (TGA), elemental analysis, and Fourier transform infrared spectroscopy (FT‐IR). The size and morphology of nanoparticles were examined by scanning electron microscopy (SEM). The XRD patterns indicate that the intercalation of YGX between the LDH layers has not occurred and surface adsorption has happened. In the adsorption experiments, the Gibbs free energy ΔG0 values, the enthalpy ΔH0, and entropy ΔS0 was determined. The isotherms showed that the adsorption of YGX by Mg‐Fe‐LDH‐NO3 was both consistent with Langmuir and Freundlich equations. 相似文献
38.
Abstract Pottery sherds from the archaeological site of Bancun (Henan, China) were analyzed by Raman microscopy and the pigments used in the coating of this ancient (c. 4000–5000 BC) pottery were determined. It was found that bauxite was used to make the white pigment. The black coating was identified as a magnetite and its particle size was in the nanometer range. This work also showed that the size of pigment had influence on the color of the coating. In principle, Raman spectra could be used not only to identify the mineral source of the pigment but also to estimate the particle size of the pigments. 相似文献
39.
UV/Vis光谱法研究红子色素的稳定性 总被引:1,自引:0,他引:1
本文报导了从红子提取,分离天然色素及酸碱和温度等对该色素稳定性的影响。 相似文献
40.
Yikun Bu Quan Zheng Qinghua Xue Yingxin Cheng Longsheng Qian 《Optics & Laser Technology》2006,38(8):565-568
A design of LD-pumped Nd:YVO4 laser that generates simultaneous laser action at wavelengths 1064 and 1342 nm by optimizing film design is presented. An optimized continuous-wave (cw) yellow laser at 593.5 nm in room temperature is obtained for the first time. Using type-I critical phase-matching (CPM)LBO crystal, a yellow laser at 593.5 nm is obtained by 1064 and 1342 nm intracavity sum-frequency mixing. The maximum laser output power of 85 mW is obtained when an incident pump laser of 1.8 W is used. The optical-to-optical conversion is up to 4.7%, and the power stability in 24 h is better than ±2.8%. 相似文献