改进化盐工艺降低酸碱消耗

介绍了采取不同配水工艺后酸碱消耗的比较情况，提出选择碱性配水化盐工艺可以降低酸碱消耗的建议。     

Latch Applicator for Efficient Delivery of Dissolving Microneedles Based on Rapid Release of Elastic Strain Energy by Thumb Force (Adv. Funct. Mater. 11/2023)

Dissolving microneedle (DMN) is an attractive alternative to parenteral and enteral drug administration owing to its painless self-administration and safety due to non-generation of medical waste. For reproducible and efficient DMN administration, various DMN application methods, such as weights, springs, and electromagnetic devices, have been studied. However, these applicators have complex structures that are complicated to use and high production costs. In this study, a latch applicator that consists of only simple plastic parts and operates via thumb force without any external complex device is developed. Protrusion-shaped latches and impact distances are designed to accumulate thumb force energy through elastic deformation and to control impact velocity. The optimized latch applicator with a pressing force of 25 N and an impact velocity of 5.9 m s⁻¹ fully inserts the drug-loaded tip of the two-layered DMN into the skin. In an ovalbumin immunization test, DMN with the latch applicator shows a significantly higher IgG antibody production rate than that of intramuscular injection. The latch applicator, which provides effective DMN insertion and a competitive price compared with conventional syringes, has great potential to improve delivery of drugs, including vaccines.     

化解乡镇债务中的博弈问题研究

我国的乡镇债务数额巨大,已严重阻碍了我国农村社会经济的可持续发展,影响到乡镇政府的正常运行。以博弈论为分析工具,深入剖析化解乡镇债务的过程与症结。乡镇债务化解过程的实质是在基层行政体制领域内的一场制度变迁,确立上级政府、乡镇政府、相关债权群体多元互动的制度格局,在这一过程中存在着多重博弈关系,即政府内部还债来源的博弈、偿债责任的博弈以及乡镇政府与债权相关人之间的博弈。     

楠竹预水解硫酸盐法制浆工艺

以楠竹为原料生产竹浆粕,对水预水解和硫酸盐法蒸煮的工艺条件进行优化。结果表明:水预水解阶段最优工艺条件为P因子1000;硫酸盐蒸煮阶段最优工艺条件为H因子1000、用碱量17%(Na2O计)、硫化度20%。按此工艺条件所得的浆粕α-纤维素含量94.55%,黏度1096mL·g-1,细浆得率33.59%,卡伯值10.76,聚戊糖含量4.81%。     

竹浆粕在漂白流程中的XPS分析

 利用X射线光电子能谱（XPS）分析了竹浆粕在制备过程中其表面化学组成随漂白流程的变化。在漂白流程中除了漂白阶段以外,其它各段竹浆表面的O/C比值增加,表明除了漂白阶段以外木质素和抽提物在竹浆表面的浓度是降低的,表面木质素和抽提物含量的计算结果表明,漂白阶段竹浆O/C比的降低主要是由于抽提物从内部迁移到表面,当终漂浆粕进一步抽提,O/C比值接近纤维素的理论值。通过分析C1s峰C1～C4的相对含量得出,竹浆的主要化学成分随漂白流程的变化而变化,证明了木聚糖酶和DMD处理具有相同的效应,即有效地脱除了半纤维素和木质素。     

Green and Effective Ammonium Carbonate-assisted Process for Drying Hemicellulose Obtained through Alkali Extraction of Bleached Bamboo Kraft Pulp

Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp fibers.Due to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is challenging.In this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction process.Hemicellulose obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying process.The effects of drying time and drying temperature were determined.Structure of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction analyses.The novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of hemicellulose.The dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films.     

粘胶纤维和Lyocell纤维生产中溶解机理的探讨

溶解技术是纤维素纤维制造过程中关键的技术,溶解的效果直接影响过滤、纺丝成形和最终产品的质量。纤维素溶解的详细机理非常复杂,但基本上都可以从分子间氢键的破坏方面得到解释,本文着重就粘胶纤维和Lyocell纤维生产中纤维素不同的溶解过程和溶解机理作了初步探讨。     

预水解硫酸盐法生产溶解浆技术

主要介绍了预水解硫酸盐法生产溶解浆的技术,重点对置换蒸煮、氧脱木素和漂白工艺的选择作了说明。     

层状盐岩小井间距双井水溶造腔流场相似模拟研究

为解决层状盐岩单井水溶造腔过程中建槽周期长,提管工艺复杂等问题,开展层状盐岩小井间距双井水溶造腔技术研究。拟采用选定物理法建立相似试验平台,探讨小井间距双井水溶造腔流场及浓度场特征,揭示双井水溶溶腔腔体扩展与流场的联系。结果表明：双井水溶造腔过程中腔体流场可以划分为4个区域：边界溶蚀区、浮羽流区、对流扩散区和底部饱和区,各个区域相互影响。浮羽流区是驱动流体运移的关键区域,根据浮羽流区流场特征建立相应的流场模型;根据宏观流动特征,对流扩散区分为强扩散区和弱扩散区;边界溶蚀区对双井水溶溶腔腔体扩展有显著影响;饱和区示踪特征不明显但浓度分层明显。通过对比分析双井造腔和单井造腔模型试验结果,发现双井水溶造腔工艺有利于盐穴建槽期,研究为小井间距双井水溶造腔技术的应用提供一定的理论基础,对盐穴储气库的优化建造具有重要意义。     

重力法连续电镀锌机组产量及相关参数计算

介绍了重力法连续电镀锌机组产能核算和电镀生产的关键参数,以及电镀槽数目、电镀电流、带钢速度及溶锌速率的计算方法。