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Bubble temperatures at 95?kPa over the entire composition range are measured for the five binary systems formed by 1,2-dimethylbenzene with 2-propanol, 1-butanol, 2-butanol, 2- methylpropan-1-ol, and 2-methylpropan- 2-ol. A Swietoslawski - type ebulliometer was used for the measurements. The composition versus temperature measurements are well represented by the Wilson model. 相似文献
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Excess molar volumes (Vm^E) of binary mixtures of 2-methyl-3-buten-2-ol[CH3C(OH)(CH3)CHCH2] with four 1-alcohols:methanol,ethanol,1-propanol and 1-butanol at 298.15K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter.All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation.The effects of chain length of 1-alcohols on Vm^E are discussed.The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively. 相似文献
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《Cement and Concrete Research》1987,17(4):602-612
Length and weight changes were measured when saturated portland cement pastes prepared at water-cement ratios of 0.3 to 1.0 were immersed in both propan-2-ol and methanol. Diffusivities and diffusion rates were determined, and were correlated with pore structure parameters, measured by mercury intrusion. Length measurements indicate that methanol interacts with the hydrated cement and is thereby unsuitable for measuring diffusivities. Propan-2-ol on the other hand is relatively inert and produces diffusivity values similar to those obtained for chloride ions in similar materials. 相似文献
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3-己炔-1-醇合成方法的研究 总被引:1,自引:0,他引:1
从乙炔出发经两步合成了3-己炔-1-醇。考察了不同烷基化试剂、反应温度、反应时间、试剂用量等因素对收率的影响,从而确定了合适的反应条件并降低了生产成本。 相似文献
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2-甲基-3-丁烯-2-醇合成3-甲基-2-丁烯-1-醇 总被引:1,自引:0,他引:1
[目的]2-甲基-3-丁烯-2-醇是异戊二烯间接皂化法生产3-甲基-2-丁烯-1-醇过程中产生的副产物,废物回收再利用是节能减排的有效措施.[方法]2-甲基-3-丁烯-2-醇经氯化、酯化和皂化得到3-甲基-2-丁烯-1-醇.[结果]结果表明:在优化条件下,氯化反应的产率可达87.25%,酯化和皂化反应的产率可达84.53%.[结论]该方法是2-甲基-3-丁烯-2-醇再利用的有效方法. 相似文献
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Concentrations in air of (Z)-9-tetradecen-1-ol formate (Z-9-tdf), a mating disruptant ofHeliothis moths, were measured intermittently over a 22-day period in a corn field. The chemical was emitted from laminated plastic (Hercon®) dispensers arranged in a square grid with 10-m spacing. Measurements were made at three heights near the center of the treated plot and 1 m downwind from disruptant dispensers. Concurrent measurements were made of wind speed, air temperature, and temperature gradient.Z-9-tdf concentrations ranged from below detectable levels to 195 ng/m3 and were generally highest in the horizontal plane of the dispenser. As wind speed decreased near sunset, concentrations increased sharply, then decreased again near midnight. SinceHeliothis moths mate in the evening and early night, the concentration pattern was favorable for mating disruption. Strong temperature inversions within the crop canopy, which occurred daily before sunset, did not apparently affectZ-9-tdf concentrations. Concentrations decreased steadily on successive sampling days after application, and, by day 27, ranged from 0 to 30% of those on day 6. The data suggest that the corn plants and the soil may act as sinks for the chemical vapor at night. 相似文献
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T. E. Vittal Prasad D. H. L. Prasad G. V. Ramserish P. Satya Kishore 《Chemical Engineering Communications》2003,190(2):171-176
Boiling point temperatures at 95 kPa over the entire composition range are measured for the three binary systems formed by 1,3-dimethylbenzene with methanol, 1-propanol, and 2-propanol. A Swietoslawski-type ebulliometer was used for the measurements. The composition versus temperature measurements are well represented by the Wilson model. 相似文献
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Alcohol oxidations under mild conditions using polyvinylpyrrolidone (PVP)-stabilized Au, Pd and bimetallic AuPd nanoparticle catalysts in aqueous solutions have been investigated. The catalytic activities of the nanoparticles towards the oxidation of benzyl alcohol, 1-butanol, 2-butanol, 2-buten-1-ol and 1,4-butanediol indicate that bimetallic 1:3 Au:Pd nanoparticles have higher catalytic activities than Au, Pd and other bimetallic AuPd nanoparticles, and that selectivities towards specific products can often be tuned using bimetallic particles. In addition, advantages and disadvantages for the use of such nanoparticle catalysts as mild, environmentally-friendly oxidation catalysts are examined. 相似文献
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本文报道了利用交叉Cannizzaro反应,合成2-甲基-3-(2-呋喃基)-2-丙烯-1-醇的一种新方法。该合成法,步骤简单;原料易得,价廉;在最佳反应条件下,产率可达58.1%。较已有文献报道的产率44%有较大幅度的提高。 相似文献
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《Catalysis communications》2005,6(7):480-484
Catalytic dehydration of 1,4-butanediol was investigated over ZrO2 with monoclinic crystal phase at temperatures of 275–425 °C. In the reaction, 3-buten-1-ol was effectively produced together with tetrahydrofuran (THF) over ZrO2 at 300–375 °C. 3-Buten-1-ol and THF were produced competitively, and the yield of 3-buten-1-ol increased with increasing the contact time. Formation of by-products such as 2-buten-1-ol, 2-butenal, and 1-butanol was suppressed over ZrO2 at 325 °C. 相似文献
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本文建立了一种用高效液相色谱测定反式-反式-2,4-己二烯醇的定量分析方法。它采用Inertsil ODS-SP C18色谱柱,以甲醇-磷酸水溶液(体积比为60∶40)为流动相,流量为1.0 mL/min,柱温为30°C,选择230 nm为检测波长进行检测。结果显示该方法的线性相关系数0.9990,标准偏差为0.092,平均回收率为100.2%。此方法简便、快速、能进行准确定量分析,结果稳定。 相似文献
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研究了以溴代异戊烯水解工艺和精馏分离工艺为基础来制备3-甲基-2-丁烯-1-醇的新工艺。通过优化溶剂种类得到当水解溶剂为偶极类溶剂乙腈时,得到产物的选择性最高。并通过进一步优化实验操作条件,得到当溶剂加入量为v(乙腈):v(溴代异戊烯)=1:1,水解温度为70℃,碱用量为n(NaOH):n(溴代异戊烯)=1.2:1和反应时间为25min时,水解部分3-甲基-2-丁烯-1-醇的转化率最高可达63.35%。水解后的料液通过间歇精馏得到纯的3-甲基-2-丁烯-1-醇,最终的3-甲基-2-丁烯-1-醇总收率达到57.4%。 相似文献
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通过水热改性氢氧化锆制备了SO42-/ZrO2固体酸催化剂。以冰乙酸和正丁醇的酯化反应为探针反应,确定了固体超强酸的最佳制备条件。分别考察了浸渍硫酸浓度、硫酸浸渍时间和焙烧温度等对催化活性的影响。并以水热改性和未经水热改性氢氧化锆制备SO42-/ZrO2固体超强酸做了对比实验,采用XRD、BET对催化剂进行了表征。实验结果表明:水热改性氢氧化锆制备SO42-/ZrO2固体酸催化剂的最佳条件是:浸渍硫酸浓度为0.5mol/L,浸渍时间是120 m in,焙烧温度500℃。乙酸正丁酯较佳的合成工艺条件是:反应温度105~110℃,反应时间2 h,n(正丁醇)∶n(冰乙酸)=2∶1,催化剂用量占反应投料总质量的0.27%,冰乙酸的酯化率达99.1%。催化剂重复使用4次后催化活性降低5%。 相似文献
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Isobaric (101.32 kPa) liquid-vapour equilibrium data for the system 1-butanol + ethanol + 2-methoxy-2-methylpropane (MTBE) were determined and fitted with Wilson, NRTL and UNIQUAC equations, and their prediction by various group contribution methods (ASOG and modified and unmodified UNIFAC methods) was examined. The NRTL equation was used to calculate, by simulation, the influence of plate number and entrainer/feed flow ratio on the quantity and composition of the distillate afforded by extractive distillation of azeotropic MTBE + ethanol using 1-butanol as the entrainer. The quantity of distillate and its MTBE content both increased with plate number, and the quantity of distillate also increased with entrainer/feed flow rate ratio. 相似文献