Electronic stopping power of hydrogen in KCl at the stopping maximum and at very low energies

The electronic energy loss of hydrogen ions in KCl was investigated in a wide energy range. Thin films of KCl were evaporated on an Au/Si substrate. Rutherford Backscattering Spectrometry (RBS) was performed with protons and deuterons at energies from 30 to 400 keV/nucleon. At lower energies experiments were performed by Time-Of-Flight Low energy ion scattering (TOF-LEIS) again with proton and deuteron projectiles. Experimental results are compared to calculated/tabulated values for the electronic energy loss. Whereas at energies beyond the stopping maximum very good agreement is found, at lower ion energies discrepancies between experiment and calculations increase. At very low ion velocities the extrapolated stopping cross section ε predicts vanishing electronic energy loss at energies below 100 eV/nucleon.     

Casein Degradation of Fynbo Cheese Salted with NaCl/KCl Brine and Ripened at Various Temperatures

ABSTRACT: Effect of temperature and salt substitution on casein degradation of Fynbo cheese was studied. Fynbo cheeses, salted in solutions of 190 g NaCl/L and of 100 g NaCl/L and 100 g KCl/L and ripened at 5, 12, and 16 °C, were sampled at 1, 5, 10, 20, 30, 60, and 90 d of ripening, at central and external zones. Samples were analyzed for moisture and chloride contents, maturation index, and casein degradation by urea‐polyacrylamide gel electrophoresis. NaCl replacement by KCl did not affect any of the parameters studied. Total salt concentration and ripening temperature affected proteolysis significantly. First‐order kinetics constants for α_s1‐casein degradation were in the range of 0.002 to 0.016 day^‐1 and the activation energy of the reaction was approximately 26 kcal/gmol.     

Elaboration and characterization of a KCl single crystal doped with nanocrystalsof a Sb2O3 semiconductor

Undoped and doped KCl single crystals have been successfully elaborated via the Czochralski（Cz） method.The effects of dopant Sb₂O₃ nanocrystals on structural and optical properties were investigated by a number of techniques,including X-ray diffraction（XRD）,scanning electron microscopy（SEM）,energy dispersive X-ray（EDAX） analysis,UV-visible and photoluminescence（PL） spectrophotometers.An XRD pattern of KCl:Sb₂O₃ reveals that the Sb₂O₃ nanocrystals are in the well-crystalline orthorhombic phase.The broadening of diffraction peaks indicated the presence of a Sb₂O₃ semiconductor in the nanometer size regime.The shift of absorption and PL peaks is observed near 334 nm and 360 nm respectively due to the quantum confinement effect in Sb₂O₃ nanocrystals.Particle sizes calculated from XRD studies agree fairly well with those estimated from optical studies.An SEM image of the surface KCl:Sb₂O₃ single crystal shows large quasi-spherical of Sb₂O₃ crystallites scattered on the surface.The elemental analysis from EDAX demonstrates that the KCl:Sb₂O₃ single crystal is slightly rich in oxygen and a source of excessive quantities of oxygen is discussed.     

Fe—Cr合金在450℃的KCl及KCl—ZnCl_2盐膜中的腐蚀

研究了Ｆｅ－１０Ｃｒ,Ｆｅ－２５Ｃｒ两种合金在４５０℃于Ｋ,Ｚｎ 氯化物中的腐蚀．结果表明,与在ＫＣｌ－ＺｎＣｌ２熔盐中的 腐蚀不同．合金无论在固态的 ＫＣｌ还是熔融态的 ＫＣｌ－ＺｎＣｌ２盐膜下均发生了加速腐蚀,且在混合盐膜下的腐蚀更为严重,合金 的耐蚀性不随 Ｃｒ含量的增加而得到改善：Ｆｅ—Ｃｒ合金在上述两种腐蚀条件下的耐蚀性差异与氧的供应量有关,并导致保护性的 氧化膜具有不同的热力学稳定性     

凝胶软糖及软糖粉的研制

本文使用一种以卡拉胶、B胶*、三聚磷酸钠、氯化钙与氯化钾复配生产凝胶软糖的方法,得出了较好的凝胶软糖粉的配方,并研究了凝胶软糖适宜的加工工艺及条件。*l－卡拉胶     

Secondary proteolysis of Fynbo cheese salted with NaCl/KCl brine and ripened at various temperatures

Effects of temperature and salt substitution on secondary proteolysis of Fynbo cheese were studied and different peaks of the chromatographic profiles were examined. Cheeses, salted in solutions of NaCl (190 g l⁻¹) and NaCl/KCl (100 g l⁻¹/100 g l⁻¹) and ripened at 5, 12, and 16 °C, were sampled during 90 days at two different zones. Samples were analysed by RP-HPLC of the trichloroacetic acid-soluble fraction. The information was successfully summarized in 2 dimensions, accounting for 86.5% of data variation using principal component analysis. The source of variation explained by PC1 (77.1% VAR) was related to the ripening time. Two groups of chromatographic peaks were distinguished according to the sign of PC2 loading. Total salt concentration and ripening temperature affected secondary proteolysis significantly, while NaCl replacement by KCl had no affect. An important peptide produced during cheese ripening (α_s1-casein (f1-23)) was tentatively identified, taking into account the chromatographic profile and the amino acid composition of the peak isolated.     

新型不锈钢材料的耐高温氧化及耐高温KCl蒸汽腐蚀性能

为缓解生物质电厂锅炉烟气侧的高温碱性环境腐蚀,对我国自主研发的4种新型不锈钢材料采用高温挂片试验(包括高温氧化试验和高温KCl蒸汽腐蚀试验)检测并绘制腐蚀动力学曲线;采用扫描电镜(SEM)、能谱仪(EDS)对试验后试片的形貌、结构、元素含量进行了分析,比较了4种新型不锈钢材料、传统TP316材料和高铬材料的耐高温氧化及耐高温KCl蒸汽腐蚀性能。结果表明:4种新型材料均表现出较好的耐腐蚀性能,明显优于传统的TP316材料和以往试验的高铬材料,当前更适用于生物质电厂锅炉烟气侧的高温碱性环境。     

影响硫酸钾产品质量的因素

为了解决硫酸钾生产中出现的质量问题，提高产品的优级品率，简要叙述了生产硫酸钾的基本原理及质量标准，考察了对硫酸钾产品中氯离子的影响因素，如反应温度、投料量、加酸量。同时考察了影响硫酸钾产品中游离硫酸的因素和原料氯化钾中氧化钾含量及反应炉的维修、加灰量、耙齿安装等因素对产品中氧化钾含量的影响，确定了曼海姆炉的生产工艺，操作指标，为生产出合格的优级品提供保证。     

Novel carboxymethyl derivatives of chitin and chitosan materials and their biomedical applications

Chitin and chitosan are natural biopolymers that are non-toxic, biodegradable and biocompatible. In the last decade, chitin and chitosan derivatives have garnered significant interest in the biomedical and biopharmaceutical research fields with applications as biomaterials for tissue engineering and wound healing and as excipients for drug delivery. Introducing small chemical groups to the chitin or chitosan structure, such as alkyl or carboxymethyl groups, can drastically increase the solubility of chitin and chitosan at neutral and alkaline pH values without affecting their characteristics; substitution with carboxyl groups can yield polymers with polyampholytic properties. Carboxymethyl derivatives of chitin and chitosan have shown promise for adsorbing metal ions, as drug delivery systems, in wound healing, as anti-microbial agents, in tissue engineering, as components in cosmetics and food and for anti-tumor activities. This review will focus on the preparative methods and applications of carboxymethyl and succinyl derivatives of chitin and chitosan with particular emphasis on their uses as materials for biomedical applications.     

辽河油田浅海钻井液技术

辽河油田滩海地区上部隔水管井段以流砂层为主，机械钻速高，环空岩屑量大，选用了正电胶钻井液；中下部地层富含以蒙脱石、伊蒙混层为主的泥岩，并且存在强坍塌应力及由沉积引起的超高压地层流体，存在井壁失稳问题；由于多个压力系统在同一裸眼段并存，油气水层相容、相近，极易发生井漏、井涌、井塌、卡钻等复杂事故，加之地层压力预测的局限，更增加了钻探难度，因此优选了海水KCl钻井液。在13口井的应用表明，海水KCl钻井液性能稳定，黏土容量限高，抗盐污染能力强，具有稳定井壁、井眼清洁、润滑防卡和保护油气层等特点，满足了辽河钻井的需要以及海洋环保的要求。