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1.
Andalusite material and Andalusite-based refractory are very popular in Europe and Japan, but its applications are restrained because of its low quality and misunderstanding in China. The paper introduced in detail the characteristics of andalusite material and andalusite-based refractory based on the authors‘ research work in recent years and on some references. Some information is illustrated clearly by figures and microstructure photographs. It is concluded the property of raw material and refractory is not determined by alumina content but by type and quantity of the impurities and microstructure.Mullitisation provide andalusite-based refractories more excellent macro and micro properties that guarantee itspopular application. 相似文献
3.
1前言据不完全统计,上个世纪90年代,全国曾有各种类型的立窑数量近万台,立窑水泥的年产量,约占我国水泥年总产量的80%以上。但是立窑生产带来的粉尘污染却十分严重,预计达千万吨之多,约占我国水泥行业粉尘年总排放量的90%。自国家经贸委发布在2000年以前,淘汰直径<2.2m的立窑和 相似文献
4.
<正> China Releases Tire Industry Policy The Ministry of Industry and Information Technology on October 11th released the tire industry policy to encourage the development of safe, energy-saving and environmental-friendly high-performance radialtires. The tires include giant OTR (off the road) tires, wide cross-section and flat passenger car radial tires and truck radial tire swith no inner tubes. By 2015, radial tires should be used for all passenger cars, and for 85% of light trucks and for 90% of heavy-duty trucks. China will focus on the development of radial tires for OTR, airplanes, and low-speed vehicles. 相似文献
7.
MnOOH and β-MnO 2 whiskers are obtained for the first time in our work. MnOOH whiskers are chemically synthesized in the presence of cationic surfactant cetyltrimethylammonium bromide (CTAB). The product is obtained under extremely low surfactant concentrations under basic conditions, using MnSO 4·H 2O as the manganese source and ethylamine as the alkali source. After the subsequent heat treatment of MnOOH at 300 °C for 1 h, β-MnO 2 whiskers retaining the similar morphologies are obtained. Powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermogravimetry analysis (TGA) are used to characterize the products. 相似文献
8.
研究了氯丁橡胶(CR)和丁苯橡胶(SBR)的动态力学性能,计算了剪切波速率.结果表明,SBR的反声效果好,适合用做声障板材料. 相似文献
9.
Transparent γ-AlON undoped and doped with one of eight rare earth elements were fabricated by hot pressing at 1850 °C. After characterizing the fundamental physical properties of sintered γ-AlON, the photoluminescence spectra of γ-AlON:Sm and γ-AlON:Yb were examined further because only these samples showed a color under visible light because of the absorbance of a certain wavelength. γ-AlON:Sm exhibited a red emission with emission peaks at 688, 701, and 729 nm, while γ-AlON:Yb exhibited a white emission due to the two broad emission peaks at 438 and 575 nm. γ-AlON:Yb revealed a possible application to UV-excited phosphor-converted white-light-emitting diodes because of its emission characteristics. The schematic crystal structure of the rare-earth-doped γ-AlON and the CIE chromaticity diagram were provided to understand the photoluminescence behavior of γ-AlON:Sm and γ-AlON:Yb. 相似文献
10.
Dermorphin analogues, containing a ( S)‐ and ( R)‐4‐amino‐1,2,4,5‐tetrahydro‐2‐benzazepin‐3‐one scaffold (Aba) and the α‐methylated analogues as conformationally constrained phenylalanines, were prepared. Asymmetric phase‐transfer catalysis was unable to provide the ( S)‐α‐Me‐ o‐cyanophenylalanine precursor for ( S)‐α‐MeAba in acceptable enantiomeric purity. However, by using a Schöllkopf chiral auxiliary, this intermediate was obtained in 88 % ee. [( S)‐Aba 3‐Gly 4]dermorphin retained μ‐opioid affinity but displayed an increased δ‐affinity. The corresponding R epimer was considerably less potent. In contrast, the [( R)‐α‐MeAba 3‐Gly 4]dermorphin isomer was more potent than its S epimer. Tar‐MD simulations of both non‐methylated [Aba 3‐Gly 4]dermorphin analogues showed a degree of folding at the C‐terminal residues toward the N terminus of the peptide, without however, adopting a stabilized β‐turn conformation. The α‐methylated analogues, on the other hand, exhibited a type I/I′ β‐turn conformation over the α‐MeAba 3 and Gly 4 residues, which was stabilized by a hydrogen bond involving Tyr 5‐H N and D ‐Ala 2‐CO. 相似文献
11.
The isolation of strontium from aqueous media may be required for environmental monitoring or nuclear forensics sample analyses. [1–4] The prevalent method is to use a strontium selective extraction chromatographic resin. Two such products are Eichrom Technologies Sr resin and IBC Advanced Technologies AnaLig® Sr-01 resin. Eichrom Technologies Sr resin utilizes a crown ether (4,4′(5′)-di-t-butylcyclohexano-18-crown-6) diluted in 1-octanol and coated onto Amberchrom TM CG71 resin, and IBC Advanced Technologies AnaLig® Sr-01 resin features a proprietary extractant covalently tethered to a silica support. The use of each resin is reported in the literature; Eichrom Sr Resin specifications, including the resin’s weight distribution ratio and capacity factor for analytes, have been reported but no such data have been published for IBC Analig® Sr-01 resin. In this work, batch studies were completed to determine the capacity and weight distribution ratio of both AnaLig® Sr-01 and Eichrom Sr resins for strontium and barium. This work shows that both resins retained Sr from aqueous samples, but Eichrom Sr resin provided superior Sr/Ba separation compared with Analig® Sr-01 resin. 相似文献
12.
Separation of trivalent lanthanides (Ln) and trivalent actinides (An) is important task in reprocessing high-level liquid waste. In this study, the relationship between structures of complexes of 2,2′-bipyridyl (Bpy) and Ln (Nd, Er) and coordination strengths were investigated by X-ray diffraction and UV titration. With the decrease in ionic radius from Nd to Er, the N(Bpy)-Ln distance and N(Bpy)-Ln-N(Bpy) angle decreased, the dihedral angle of the Bpy pyridines increased, and the stability constant increased. This information about structure and coordination strength is important for designing better ligands for separating Ln and An ions. 相似文献
13.
A thorough investigation of the reactions of diynes, R(C&tbd1;C)(2)R, and polyynes, R(C&tbd1;C)(n)()R, with titanocene and zirconocene was performed using the metallocene sources Cp(2)M(L)(eta(2)-Me(3)SiC&tbd1;CSiMe(3)) (M = Ti, L = -; M = Zr, L = THF, pyridine). The conversions show an array of different products generated in complexation, coupling, and cleavage reactions. These results include remarkable structures (e.g., five-membered metallacyclocumulenes) and reactions (e.g., C-C single-bond cleavage). In addition, the first C-C single-bond metathesis in homogeneous solution was discovered. The presented findings have been supported by theoretical studies. 相似文献
15.
National Quality Supervision & Inspection Center for Refractories Business scope: Selective examination for national quality supervision; Identification of production license; Arbitration inspection and technical achievements evaluation; Commodities inspection and otherquality inspections . 相似文献
16.
ory and PracticeLibrary Theory and PracticeLibrary 浩诩洳∏槲榷ǖ男律?0例,抚触组和对照组各25例。抚触组15min/次,10d为一个疗程,3个疗程后两组对照。结果有效率抚触组患儿睡眠时间为80%,可安慰性为92%,前臂弹回为84%,手握持为88%,而对照组分别为48%、40%、36%和40%。经卡方检验有显著意义(P<0.01)。结论抚触有利于神经系统发育及体格发育,该方法简便易行,易于推广应用。 相似文献
18.
The aim of this study, is to describe the effects of adhesives (PVAc-Desmodur VTKA and Urea formaldehyde) on wooden materials (walnut and poplar) cut tangentially and radially impregnated with Protim Solignum, CCA and Celcure AC 500 and exposed to: humid–water–heat resistance; heating; and cooling tests. All these tests show a decreased in bonding strength. The conclusion is that poplar wood cut tangentially and impregnated with CCA, bonded with D-VTKA adhesive can be used as a material in damp conditions where good bond strength is required. 相似文献
19.
In this paper, undoped and Pb-doped ZnO thin films have been prepared by sol gel method and deposited on glass substrate using dip-coating technique. The structural, morphological, and optical properties of the films were investigated as a function of Pb doping. The results of the structural tests showed that these films are of a polycrystalline hexagonal structure with a preferred orientation in the (002) direction. The grain size values of Pb-doped films were lower than that of pure ZnO, but the strain and the dislocation density values inecrease with increase Pb doping ratio. The atomic force microscopy (AFM) images showed that the particle size and Root Mean Square (RMS) of ZnO decrease with increasing Pb doping. The optical band gap values were found to increase from (3.19 to 3.30 eV) and the Urbach energy decrease from (322 to 313 meV). PL spectra exhibit an increased amount of defects with increasing Pb, which leads to a red shift in the UV region. 相似文献
20.
Gossypol is a sesquiterpene that occurs naturally in seed and other parts of the cotton plant. Because of restricted rotation around the binaphthyl bond, it occurs naturally as enantiomeric mixtures with (+)-gossypol to (−)-gossypol ratios that vary between 97:3 and 31:69. Commercial cotton varieties ( Gossypium hirsutum) normally exhibit an approximate 3:2 ratio. (+)-Gossypol is significantly less toxic than (−)-gossypol to nonruminant animals; thus, cottonseed containing high levels of (+)-gossypol might be safely fed to nonruminants. Gossypol, however, is an important component in the cotton plant's defense against insect herbivores, but it is not known how cotton plants that exhibit high levels of (+)-gossypol in the foliage might be affected by insect herbivory. To address this question, 1-d-old Helicoverpa zea larvae were fed diets with 0.16, 0.20, and 0.24% racemic, (+)-, and (−)-gossypol. Larval pupal weights, days-to-pupation, and survival were adversely affected by all gossypol diets compared with the control diet. Statistical differences were determined by comparing the compounds among themselves at the three levels and between the three compounds at the same level. When the compounds were compared among themselves, no large differences were observed in pupal weights or in days-to-pupation among any of the diets. Among the three compounds, at the 0.16% level, the diet containing racemic gossypol was the most effective at reducing survival. At the 0.20 and 0.24% levels of racemic (+)- and (−)-gossypol, survival was not statistically different. The overall results indicate that (+)-gossypol is as inhibitory to H. zea larvae as racemic or (−)-gossypol, and thus, cotton plants containing predominantly the (+)-enantiomer in foliage may maintain significant defense against insect herbivory. 相似文献
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