脱氢枞基咪唑啉的制备及结构表征

对脱氢枞酸二乙烯三胺盐(Ⅱ)进行热重分析,提出了一种制备脱氢枞基咪唑啉(Ⅳ)的方法。将脱氢枞酸(Ⅰ)用带水剂二甲苯溶解,滴加到热的二乙烯三胺(DETA)中进行高温液液短接触脱水缩合反应,得到产品;DETA既是反应物,又是产品的不良溶剂,还起到调控反应温度的作用;二甲苯受热快速蒸发并将反应生成的水带离反应体系。反应结束后,该产品易于从反应混合物中冷却结晶析出、过滤分离,经元素分析、红外光谱、紫外光谱、1HNMR及13CNMR核磁共振谱的波谱结构表征确证。反应物料比可以改变反应体系的温度,进而对产品产率与外观色泽有较大的影响;在化合物Ⅰ的用量为30 mmol、DETA与化合物Ⅰ的物质的量之比为15.7、反应温度为210℃的条件下,产品产率为86.0%。     

三甘醇脱水效果的影响因素分析

为了提高三甘醇脱水的脱水效果,有必要分析各种因素对脱水效果的影响。利用HYSYS软件对处理量为100×10^4Nm^3／d的三甘醇脱水装置进行模拟计算,分析结果显示吸收塔的吸收温度越低、三甘醇贫液浓度越高、三甘醇循环量越大、吸收塔塔板数越多,则脱水效果越好,外输干气水露点越低。‘     

饱水竹木漆器的超临界CO2脱水干燥研究

用超临界CO2对战国时代的饱水竹木漆器(含水率大于200%)进行脱水干燥。结果表明,超临界CO2脱水干燥的最优工艺条件为:干燥温度50℃,压力25 MPa,CO2流量为20 kg/h,脱水干燥5h。在该条件下,脱水干燥的竹木漆器,其含水率下降到了15%以下,漆皮完好如初,色泽鲜亮,样品形状完好、无收缩开裂损坏等现象,符合文物脱水保存的要求。     

一种4-甲基邻苯二甲腈的合成方法

介绍了一种采用酰胺脱水法合成4-甲基邻苯二甲腈的方法,同时考察了反应温度、时间和脱水试剂等因素对收率的影响。以4-甲基苯酐为原料,通过氨解反应得到4-甲基邻苯二甲酰胺,再经过脱水反应得到扣甲基邻苯二甲腈。同时确定了脱水反应的最佳条件：选择三氯氧磷为脱水试剂,65-70℃反应5h。产物经红外结构鉴定,总收率为74。7％。...     

饱水竹木漆器的超临界CO_2脱水干燥研究

用超临界CO2对战国时代的饱水竹木漆器（含水率大于200%）进行脱水干燥。结果表明,超临界CO2脱水干燥的最优工艺条件为：干燥温度50℃,压力25 MPa,CO2流量为20 kg/h,脱水干燥5h。在该条件下,脱水干燥的竹木漆器,其含水率下降到了15%以下,漆皮完好如初,色泽鲜亮,样品形状完好、无收缩开裂损坏等现象,符合文物脱水保存的要求。     

Enhanced production of hydroxymethylfurfural from fructose with solid acid catalysts by simple water removal methods

This paper demonstrates two simple ways to increase 5-hydroxymethylfurfural (HMF) yield (selectivity) in fructose dehydration with various solid acid catalysts. One is a water removal from the reaction mixture by a mild evacuation at 0.97 × 10⁵ Pa; it increases HMF yield for various catalysts (heteropoly acid, zeolite, and acidic resin). The removal of water suppresses two undesired reactions: the hydrolysis of HMF to levulinic acid and the reaction of partially dehydrated intermediates to condensation products. The other method is a decrease in the particle (bead) size of the resin (Amberlyst-15). The crushed and sieved Amberlyst-15 powder in a size of 0.15–0.053 mm shows 100% HMF yield at high fructose concentration (50 wt.% in DMSO), which is to our knowledge the highest yield to date. Near-infrared spectroscopic characterization of adsorbed water suggests that the enhanced yield can be caused by an improved removal of adsorbed water in a small-size resin particle.     

基于响应面分析的刺参渗透脱水工艺

由于刺参离开海水后很快会发生自溶,所以刺参一般都是脱水后在市场上流通.传统的刺参干制方法耗时太长,而且品质较差.渗透处理可有效降低刺参的初始含水率,几乎没有额外能耗,因此可有效降低后续干燥处理的能耗.采用可旋转的中心组合试验,利用响应面分析方法,对刺参在渗透过程中的主要工艺参数对失水率和固形物增加率的影响进行分析,并得到优化的渗透工艺参数.     

丙三醇和丙二醇热裂解生成羰基化合物研究

为了解保润剂对卷烟感官质量和有害性的影响,采用正交试验方案研究了热解温度、氮气流量和氧气浓度对丙三醇和丙二醇裂解生成的8种挥发性羰基化合物的影响。结果表明:①氮气流量是丙三醇和丙二醇裂解生成甲醛的主要影响因素,除丙二醇裂解生成丙烯醛和巴豆醛外,其他7种挥发性羰基化合物的主要影响因素都是裂解温度;②相同条件下丙三醇的甲醛、丙烯醛和巴豆醛产生量显著高于丙二醇,800℃下丙二醇裂解产生的丙酮、丙醛和甲乙酮量显著高于丙三醇;③丙二醇和丙三醇热裂解产物甲醛、乙醛、丙烯醛、丙醛和丙酮产生量的不同可能是其分子中的C-O和C-C键能的差别造成的;④就危害性和感官质量而言,丙二醇作卷烟保润剂的效果应好于丙三醇。     

Experimental evaluation of Pt/TiO2/rGO as an efficient HER catalyst via artificial photosynthesis under UVB & visible irradiation

The study investigated the synergistic effects of rGO and Pt over TiO₂ for the HER via artificial photosynthesis under UVB and visible light irradiation. The introduction of glycerol and industrial wastewater to the system as sacrificial reductants signifies that the major reaction pathway is photocatalytic partial water splitting. The material characterizations revealed successful heterojunction formation and provided insight into chemistry behind the activity of the photocatalysts. Amongst various combinations of rGO on TiO₂, 1GNT exhibited an HER yield five times that of bare TiO₂ under UVB light. Addition of Pt led to the formation of a strong Schottky barrier at the heterojunction and consequently boosted HER performance. 1P0.5 GT presented the highest of 28.5 mmol g⁻¹ h⁻¹ with glycerol and 9.6 mmol g⁻¹ h⁻¹ with wastewater under UVB light respectively. For both binary and ternary photocatalysts, the HER performances dwindled under visible light irradiation, accentuating the insufficient activation of the TiO₂. In addition, 1PT outperformed all the other photocatalysts thereby elucidating the impression that rGO and Pt does not work well together in enhancing HER despite quenching the exciton recombination rate of TiO₂ significantly. The role of pH in the synthesis and the experiments has been discussed. Finally, the underlying mechanisms in the photodeposition and photoreformation have been proposed.     

造纸污泥深度脱水装备的应用试验:太阳纸业污泥半干化脱水

正造纸污泥是造纸厂废水处理后排放出来的终端产物,包括初沉污泥、生化污泥和脱墨污泥。先进的制浆造纸企业生产每吨浆纸约产生废水10～20m3,处理每吨废水约产生3.6kg绝干污泥。2010年,全国浆纸产量为9270万吨,年产污泥约333万～669万吨。可见,制