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1.
以丙烯酸丁酯(BA)为软单体、丙烯酸甲酯(MA)为硬单体、2-乙基己烷丙烯酸酯(2-EHA)为特软单体、丙烯酸(AA)为亲水单体、二甲基丙烯酸乙二醇酯(EGDM)为交联剂、平平加(O-25)和十二烷基硫酸钠(SDS)为复合乳化剂、过硫酸钾(KPS)和偏重亚硫酸钠(SM)为氧化还原型引发剂,采用乳液共聚法合成环保型静电植绒胶。结果表明:当m(BA)∶m(MA)∶m(2-EHA)∶m(AA)∶m(EGDM)∶m(0-25/SDS)∶m(KPS/SM)=100∶40∶4∶8∶3∶(26/7)∶(1/1.0)时,胶粘剂稳定性较好;此时静电植绒织物中无游离甲醛含量和APEO含量,其摩擦牢度2 500次且柔软度为4~5级,符合生态服装面料的使用要求。  相似文献   

2.
王煜  方志杰  汪建敏 《精细化工》2007,24(12):1212-1214,1235
对合成结构较简单的4种以芳基取代丙烯腈为骨架的芪类化合物的常用合成方法进行了研究。以取代苯甲醛和取代苯乙腈为原料,在氮气保护、甲醇钠作催化剂等条件下,通过一步缩合反应,高收率得到(Z)-2-(3,4-二甲氧苯基)-3-(4-甲氧苯基)丙烯腈(Ⅰ)、(Z)-2-(3,4-二甲氧苯基)-3-(3,4-二甲氧苯基)丙烯腈(Ⅱ)、(Z)-2-(3,4-二甲氧苯基)-3-(4-二甲氨基苯基)丙烯腈(Ⅲ)、(Z)-3-(3,5-二甲氧苯基)-2-(4-甲氧苯基)丙烯腈(Ⅳ),实测收率分别为98.3%、96.0%、83.4%及88.8%。  相似文献   

3.
宋建华  许家瑞  梁淑霞 《化学世界》2004,45(7):342-343,347
探讨了用电导法跟踪高反应活性的五配位硅钾化合物与2-氯乙醇反应制备双羟基四配位硅化合物的动力学行为,从而确定该反应的反应级数为二级反应,得出在甲醇体系中反应的速率常=1.233h、t53℃=数k64℃=1.818(mol/dm3)-1·h-1、k53℃=0.4437(mol/dm3)-1·h-1,半衰期t64℃11225.051h,和该反应的活化能Ea=86.987kJ/mol。  相似文献   

4.
The chemistry of chrome mordanting is discussed under the headings: reaction of wool with chromium(VI) anions; reaction of wool with chromium(III) cations; reduction of chromium(VI) to chromium(IlI); interaction between chromium(Vl) and dye; interaction between chromium(III) and dye; and interaction between chromium(III), dye and wool.  相似文献   

5.
以温度为函数的硝仿系炸药的爆发分解反应动力学参数   总被引:2,自引:0,他引:2  
用爆发点试验装置测定了6种硝仿系炸药:2,2,2-三硝基乙基-N-硝基-甲胺(TNMA)、二(2,2,2-三硝基乙基-N-硝基)乙二胺(BTNEDA)、4,4,4-三硝基丁酸-2,2,2-三硝基乙酯(TNETB)、二(2,2,2-三硝基乙醇)缩甲醛(BTNF)、1,1,1,3-四硝基丙烷(TETNP)和二(2,2,2-三硝基乙基)硝胺(BTNNA)在不同温度下的爆发延滞期.依据谢苗诺夫方程lnt_(lag,i)=E_α/RT_i-lnA_α,由lnt_(lag,i)对1/T_i的关系,用作图法和最小二乘法计算了爆发分解反应的表观活化能(E_α)、指前因子(A_α)和5 s爆发点.用非线性等转化率积分法所得的表观活化能(E_α)校验了由lnt_(lag,i)~1/_Ti关系得到的Eα值.借助热力学关系式,计算了爆发分解反应的活化热力学参数[活化自由能(ΔG≠),活化焓(ΔH≠)和活化熵(ΔS≠)].结果表明: (1) E_α和作图法所得E_α间的相对误差在±5%以内; (2) E_α与最小二乘法所得E_α相等的事实佐证了不同温度下爆发分解反应延滞期内的分解深度是相等的,所得E_α和A_α值是可接受的,谢苗诺夫方程推导过程中采用A_α>>G(α)的假设是合理的; (3) 以5 s爆发点和ΔG~#为判据,6种硝仿系炸药对热抵抗能力的次序为:TNETB>BTNF>BTNEDA>TETNP>TNMA>BTNNA.  相似文献   

6.
Some organotin(IV) and tin(II) complexes of composition R(3)Sn[R'COC:CON(C(6)H(5))N:CCH(3)] (where R=C(4)H(9), R'=CH(3), C(3)H(5), p-ClC(6)H(4); R=C(6)H(5), R'=C(6)H(5) and p-ClC(6)H(4)) and Sn[p-ClC(6)H(4)COC:CON(C(6)H(5))N:CCH(3)](2) were screened for their toxicity against Aedes aegypti larvae. Organotin(IV) complexes were more active than tin(II) complexes.  相似文献   

7.
A number of catalysts of Pd(II), Pt (II), Rh (I) and Ir(I) induce rearrangements of O-allylic-S-methyl dithiocarbonates at 25° C. For most substrates, the Pd(II) and Pt(II) catalysts cause [3,3] sigmatropic (Claisen) rearrangements but the Rh(I) and Ir(I) catalysts give, in addition, other products depending on the catalyst and the substrate. The Claisen rearrangements observed with the Pd(II) and Pt(II) catalysts are believed to occur by a cyclization induced mechanism, whereas those rearrangements associated with the Rh(I) and Ir(I) catalysts, as well as in one case with the Pd(II) catalyst, appear to involve metal stabilized carbocation intermediates. When cyclic substrates are used retention of configuration is observed predominantly for all catalysts tried.  相似文献   

8.
The polymeric procyanidins extracted from Acacia confusa stem bark were fractionated with a step gradient of water, methanol and acetone on a Sephadex LH-20 column. The antioxidant activity of the collected fractions was investigated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing/antioxidant power (FRAP) assays. All fractions possessed potent antioxidant activity with the highest activity observed for fraction F9. The matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and reversed-phase high performance liquid chromatography (RP-HPLC) analyses suggested that the collected fractions consisted primarily of oligomeric and polymeric procyanidins, with different polymer ranges and most abundant polymer size. For each fraction, catechin and epicatechin were present as both terminal and extension units, and epicatechin was the major component in the extended chain. The mean degree of polymerization (mDP) of each fraction differed, ranging from 1.68 (fraction F2) to 17.31 (fraction F11). There was a relationship between antioxidant activity (IC50/DPPH and FRAP) and mDP (R(2) (DPPH) = 0.861, P = 0.006 and R(2) (FRAP) = 0.608, P = 0.038), respectively. However, the highest antioxidant activity of fraction (F9) was not coincident with the maximum mDP of fraction (F11).  相似文献   

9.
Membrane proteins are made soluble in aqueous buffers by the addition of various surfactants (detergents) to form so-called protein-detergent complexes (PDCs). Properties of membrane proteins are commonly assessed by unfolding the protein in the presence of surfactant in a buffer solution by adding urea. The stability of the protein under these conditions is then monitored by biophysical methods such as fluorescence or circular dichroism spectroscopy. Often overlooked in these experiments is the effect of urea on the phase behavior and micellar microstructure of the different surfactants used to form the PDCs. Here the effect of urea on five polyoxyethylene surfactants - n-octylytetraoxyethylene (C(8)E(4)), n-octylpentaoxyethylene (C(8)E(5)), n-decylhexaoxyethylene (C(10)E(6)), n-dodecylhexaoxyethylene (C(12)E(6)) and n-dodecyloctaoxylethylene (C(12)E(8)) - is explored. The presence of urea increases the critical micelle concentration (CMC) of all surfactants studied, indicating that the concentration of both the surfactant and urea should be considered in membrane protein folding studies. The cloud point temperature of all surfactants studied also increases with increasing urea concentration. Small-angle neutron scattering shows a urea-induced transition from an elongated to a globular shape for micelles of C(8)E(4) and C(12)E(6). In contrast, C(8)E(5) and C(12)E(8) form more globular micelles at room temperature and the micelles remain globular as the urea concentration is increased. The effects of increasing urea concentration on micelle structure are analogous to those of decreasing the temperature. The large changes in micelle structure observed here could also affect membrane protein unfolding studies by changing the structure of the PDC.  相似文献   

10.
The fate of major and minor components of soybean oil is examined at each stage of processing. Relationships are then drawn upon the effect on the quality of finished oil. General topics covered are (a) triglycerides and polyunsaturated fatty acids, (b) free fatty acids, (c) mono- and diglycerides, (d) phospholipids, (e) minor constituents, such as tocopherols, color bodies, and metal ions, (f) rearrangement and decomposition products, (g) foreign or toxic compounds not native to soya and (h) other additives, such as refining aids.  相似文献   

11.
The antifertility activity of organoantimony(III) complexes PhSb[RC(NC(6)H(4)S)CH(2)(NC(6)H(4)S)CR'] {R' = CH(3) (R(1)) and R = R' = CF(3) (R(2))} derived from corresponding sterically hinlered bifuinctional tetradentate ligands in the male rats was determined. The administration of compounds R(1) and R(2) at the dose level of 20 mg/kg. b. wt. siignificantly reduced the weights of testes and epididymides. Auxiliary glands showed a significant reduction after the treatment of compound R(1) only. Treated animals showed a notable depression of spermatogenesis. The preleptotene spermatocytes were decreased by 76.19 and 47.06; the secondary spermatocytes by 87.4% and 54.87337; and the step-19 spermatids by 72.9 and 46.77% respectively, following the compound R(1) and R(2) treatment. Reduced sperm count and motility resulted in 100% negative fertility in both the treated groups. A significant fall in the content of various biochemical parameters of eproductive tissues was observed after R(1) and R(2) treatment in comparison to controls.  相似文献   

12.
两种4-羟基吡啶(HP)的盐酸盐:HP.HCl(A)和(HP)2.HCl.H2O(B)具有不同的晶体结构,但在水溶液中它们应该是同样的HP共轭酸碱体系。为了得到HP合成工艺中需要的等电点(I)和离解常数Ka1两项参数和有必要证明在水溶液中(A)和(B)是同样的共轭酸碱体系,用pH计测定的酸碱滴定法,测定了HP的等电点(I)和离解常数Ka1,证明(A)和(B)是同样的共轭酸碱体系,并对上述参数进行了不确定度评定。  相似文献   

13.
Benzoic acid containing synthetic solution was pretreated by acid precipitation at various pH (1-3) and temperature (15-60 °C). Pre-treated solution was further treated by electrocoagulation (EC) and electrochemical Fenton (EF) processes using iron anode and graphite cathode. Optimization of independent operating parameters, namely, initial pH: (3-11), current density (A/m2): (15.24-76.21), electrolyte concentration (mol/L): (0.03-0.07) and electrolysis time (min): (15-95) for EC process and pH: (1-5), current density (A/m2): (15.24-76.21), H2O2 concentration (mg/L): (100-500) and electrolysis time (min): (15-95) for EF process, was performed using central composite design (CCD) in response surface methodology (RSM). Maximum removal efficiencies of BA- 76.83%, 88.50%; chemical oxygen demand (COD) - 69.23%, 82.21% and energy consumption (kWh/kg COD removed) - 30.86, 21.15 were achieved by EC and EF processes, respectively, at optimum operating conditions. It was found that EF process is more efficient than EC process based on removal of BA and COD with lower energy consumption. The sludge obtained after EC and EF treatments was analyzed by XRD, FTIR, DTA/TGA and SEM/EDX techniques.  相似文献   

14.
Mercaptoacetyltriglycine forms complexes with (186/188)Re and (99m)Tc radionuclides that are useful in nuclear medicine because they are substrates of the renal anion transport system. However, the renal clearance of [MO(MAG(3))](2-)(MAG(3) = penta-anionic form of mercaptoacetyltriglycine, M = Re, Tc) complexes are less than ideal. Organic sulphonates are also transported by the renal anion transport system and phosphonates are similar to sulphonates in size and shape. In an effort to develop new ligands that form Re and Tc complexes and have improved renal clearances compared to [MO(MAG(3))](2-) complexes, the sulphonate and phosphonate derivatives of mercaptoacetyltriglycine were synthesized. The dianion [ReO(MAG(2)-AMS)](2-) (MAG(2)-AMS = penta-anionic form of mercaptoacetylglycylglycylaminomethanesulphonic acid) was prepared for characterization by exchange reaction of ReOCl(3)(Me(2)S)(OPPh(3)) and isolated as the disodium salt. The structure of Na(2)[ReO(MAG(2)-AMS)].3H(2)O (6) was determined by X-ray diffraction. The coordination geometry is pseudo square pyramidal, with the nitrogen and sulfur donor atoms forming a square base and the oxo ligand at the apex. The deprotonated sulphonate group has a syn conformation with respect to the oxo ligand. The renal clearances of [(99m)TcO(MAG(2)-AMS)](2-) and [(99m)TcO(MAG(2)-AMP)](3-) were similar in rats and suggest that the difference in total charge between the SO(3) (-) and PO(3) (2-) groups is not important to renal clearance. However, their renal clearances were 40-50% less than that of [(99m)TcO(MAG(3))](2-) suggesting that the size and shape of the large tetrahedral SO(3) (-) and PO(3) (2-) groups of [(99m)TcO(MAG(2)-AMS)](2-) and [(99m)TcO(MAG(2)-AMP)](3-) inhibit recognition by the renal transport system compared to the small planar CO(2) (-) group of [(99m)TcO(MAG(3))](2-).  相似文献   

15.
Malignant pleural mesothelioma (MPM) cells are characterized by chemoresistance associated with glutathione (GSH) metabolism. Ethacrynic acid (EA) is able to inhibit the detoxifying enzyme glutathione-S-transferase (GST), which catalyzes the conjugation between GSH and Pt-based drugs. With the aim of obtaining active bifunctional drugs, a Pt(II) complex containing two EA moieties as leaving groups, namely cis-diamminobis(ethacrynato)platinum(II), was synthesized, characterized, and tested on four MPM cell lines. The resulting antiproliferative activity was compared with that elicited by the analogue Pt(IV) complex, cis,cis,trans-diamminodichloridobis(ethacrynato)platinum(IV) (ethacraplatin) and by the co-administration of free EA and cisplatin. The Pt(II) and Pt(IV) bifunctional complexes showed poorer performance than the reference drug cisplatin alone or in combination with EA. After treatment, cellular GST activity remained consistently unchanged, while the GSH level increased.  相似文献   

16.
Hydrothermal Growth of Large Sound Crystals of Zinc Oxide   总被引:7,自引:0,他引:7  
Large (10 to 20 g) macroscopically sound ZnO crystals suitable for preliminary transducer and other studies have been grown hydrothermally at rates of from 10 to 15 mils per day. The factors found to be important in achieving good growth were (1) base concentration of growth solution, (2) temperature difference between dissolving and growth regions, (3) presaturation of growth solution, (4) warm-up procedure, (5) addition of Li+ to the growth solution to suppress dendrite formation, (6) etching to remove seed damage, and (7) nutrient size. Each of the foregoing factors was studied and is discussed.  相似文献   

17.
以1-(2-甲基丙基)-4-氯-1H-咪唑并[4,5-c]喹啉(Ⅰ)为原料与哌啶反应合成了1-(2-甲基丙基)-4-[哌啶-1-基]-1H-咪唑并[4,5-c]喹啉(Ⅱ),当用甲苯为溶剂,n(Ⅰ)∶n(哌啶)∶n(K2CO3)=1∶2∶0.3时,Ⅱ的收率为88.5%;Ⅰ与三倍过量的吗啉反应合成1-(2-甲基丙基)-4-[吗啉-4-基]-1H-咪唑并[4,5-c]喹啉(Ⅲ),收率86.5%;Ⅰ与三倍过量的哌嗪在体积分数50%的1,4-二氧六环水溶液中反应合成1-(2-甲基丙基)-4-[哌嗪-1-基]-1H-咪唑并[4,5-c]喹啉(Ⅳ),收率59%。Ⅱ、Ⅲ、Ⅳ的合成工艺均较简单。  相似文献   

18.
The oxidation of naphthalene (1) (Scheme 1) in dichloromethane or acetonitrile with excess ozone gives phthalic aldehyde (3), 2-formyl benzoic acid (4) and phthalic anhydride (8). Small amounts of the (E)- and (Z)-isomer of 3-phenyl-(2-formyl)-propenal (10) and (11) are also observed in some cases. The reaction is faster in acetonitrile than in dichloromethane owing to the higher solubility of ozone in the former solvent. The reaction is faster on lowering the temperature because of the increase of the concentration of ozone in solution at lower temperature. With a 1:1 or a 1:2 naphthalene:ozone ratio high conversion and low selectivity for the anhydride (8) is observed.  相似文献   

19.
Cobalt, being essential metal, influences different physiological and enzymatic functions. As cobalt does not accumulate in the body, Co-compounds have relatively low toxicity. The aim of the present study is the effect of complexes of Co(II) with aminoacids - lysine, arginine, histidine and serine on HSV-1 replication. No effect of [O(2)Co(his)(4)].nH(2)O and [O(2)Co(arg)(2)].nH(2)O on HSV-1 infection in vitro was found. Both, [O(2)Co(lys)(2)].nH(2)O and [O(2)Co(ser)(2)].nH(2)O suppress the attachement of HSV-1 particles onto target cells and the viral replication as well. Moreover, the properties of the particular Co-complex (charge, stability, structure) are manifestated by their virucidal effect. Thus, [O(2)Co(ser)(2)].nH(2)O irreversibly inhibits the infectious activity of free HSV-1 virions, while virucidal effect of [O(2)Co(lys)(2)].nH(2)O is completely reversible after the 2h of contact.  相似文献   

20.
皮肤美白剂活性的化学评价研究   总被引:2,自引:0,他引:2  
刘宇红  李才广  彭金乱 《精细化工》2000,17(6):318-320,368
采用化学评价法 ,即通过测定皮肤美白剂对酪氨酸酶的活性抑制率 ,对目前常用的 6种皮肤美白剂的活性进行了评价 ,并与氢醌进行比较 ,得出 :( 1)各美白剂对酪氨酸酶活性的最高抑制率 ( 3 5h下 ) ,按由大到小次序排列如下 :氢醌 ( 98 3% ) >Biowhite( 90 5 % ) >Vc( 88 2 % )≥熊果苷 ( 87 8% )≥曲酸 ( 86 2 % ) >Vc磷酸酯钠 (自制 ,72 9% )≥Vc磷酸酯钠 (进口 ,72 7% ) >Vc磷酸酯镁 ( 41 1% )。探讨了美白剂活性评价与酪氨酸酶抑制率高低的关系。 ( 2 )得出各美白剂的ICmax( 3 5h下 )。 ( 3)得出美白剂作用时间与其酪氨酸酶抑制率关系曲线 ,该曲线表明 ,美白剂对酪氨酸酶的抑制率随其作用时间的增加而增加 ,时间过短将影响美白效果。采用自制酪氨酸酶体系进行评价 ,是一个行之有效的经济实用的方法  相似文献   

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