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161.
采用强化高温成熟现代工艺(36℃强化高温成熟45 d,用盐量6.5%,以火腿质量计)制作干腌火腿,分析加工过程中火腿半膜肌盐分含量、水分含量、p H值、色差值、肌红蛋白氧化状态、血红素类色素和锌卟啉(Zn-protoporphyrin,Zn-PP)Ⅸ含量,研究火腿色泽的形成及KCl替代Na Cl对火腿加工过程中色泽变化的影响。结果表明:盐量30%KCl替代Na Cl对干腌火腿产品理化特性、色差值及色素状态和含量没有显著影响(P0.05);干腌火腿的独特色泽是由肌红蛋白的氧化状态、红色色素的含量及肌肉组织的状态共同形成的,火腿加工过程中氧合肌红蛋白(oxymyoglobin,OMb)和高铁肌红蛋白(metmyoglobin,MMb)相对含量分别上升约22.07%和25.21%,脱氧肌红蛋白(deoxymyolglobin,DMb)相对含量下降约47.27%,DMb与亮度L*值呈极显著正相关(P0.01),OMb、MMb与L*值呈极显著负相关(P0.01),并受OMb与MMb相对含量比值极显著影响(P0.01)。在较低范围内(0%~27.49%),MMb相对含量越高红绿度a*值越大,并且MMb的影响力大于OMb。血红素类色素和Zn-PPⅨ含量在火腿加工过程中都显著增加,约394%和5 296%,并与a*值和色饱和度C值呈极显著正相关关系(P0.01)。  相似文献   
162.
金河1井有机盐氯化钾高密度钻井液技术   总被引:2,自引:2,他引:2  
金河1井是位于准噶尔盆地南缘霍尔果斯背斜沙湾组断鼻构造上的一口探井.完钻井深为2 225 m.由于该构造地层压力系数高、地层倾角大、成岩性差、破碎严重,黏土矿物中蒙脱石含量最高达70%以上,钻进过程中频繁出现卡钻、垮塌、井漏等复杂事故.采用有机盐KCl钻井液,在高密度下兼顾钻井液抑制性、流变性、封堵防塌性,实现了钻井作业零事故.经现场应用表明,有机盐KCl高密度钻井液顺利钻穿金河1井高陡山前构造安集海河组700m厚地层,钻井作业中井壁稳定、井眼畅通;全井流变性能优良易控,钻进中扭矩平稳,砂样代表性好,钻屑基本呈原生片状且棱角分明,电测井径规则,钻井液封堵能力强,在完井液中不添加堵漏剂的情况下承压能力达到4MPa,电测一次成功率为100%,下套管固井一次成功,钻井周期仅为110d.  相似文献   
163.
东胜气田钻井液废弃物处理与钻井液技术   总被引:2,自引:0,他引:2  
东胜气田某水平井钻探过程中应用钻井液不落地技术,通过电化学处理、沉淀、加药调整各项性能之后再次参与循环,岩屑无害化处理以降低废弃物污染。但钻井液中直径5μm的固体颗粒没有完全清除,颗粒累积后会污染钻井液。污染后的钻井液导致各类井下复杂频发。这样会增加钻井成本,甚至使施工井报废。试验应用的氯化钾聚合物钻井液体系解决井壁失稳和井漏问题。对合理应用不落地技术和氯化钾聚合物钻井液体系提供了参考依据。  相似文献   
164.
《Soils and Foundations》2014,54(3):329-344
The performance of landfill liners can be enhanced if they exhibit a semipermeable membrane behavior, which restricts the migration of contaminants. Consequently, enhancing the membrane property of clays used for liners is becoming increasingly important. As bentonite has already proven to be an excellent additive for improving the membrane behavior of clay, the hydraulic conductivities and membrane behaviors of a locally available clay, known as Fukakusa clay, amended with different amounts of dry bentonite (5%, 10%, 15%, and 20%) were herein evaluated. The chemico-osmotic efficiency coefficient, ω, was obtained under different concentration differences of KCl solution (0.5, 1, 5, 10, and 50 mM) for specimens in rigid-wall cells. The test results show that the ω of unamended clay is very low and can be ignored unless amended with bentonite, and that hydraulic conductivity k is suitably low (1.58×10−9 m/s). Additionally, ω decreased as the KCl concentration increased, which is consistent with the theory that increasing concentration causes progressively greater shrinkage of the diffuse-double layers of the clay particles. Furthermore, the mechanisms that influence the membrane behavior are discussed from the viewpoints of the diffuse-double layer and the interparticle pore size with the assistance of SEM.  相似文献   
165.
Ni3Sn2 and several Co–Sn alloys prepared by electrodeposition in molten LiCl–KCl were studied as anode materials in rechargeable Li-ion battery. In the case of Ni3Sn2, the charge–discharge curves do not exhibit any plateau in contrast with Co–Sn alloys. For Ni3Sn2, the reversible capacity and the coulombic efficiency tend to constant values of about 225 mAh/g and 85%, respectively, after subsequent cycles. Among the studied Co–Sn alloys, the best electrochemical performances was observed when CoSn2 was used as anode material: the reversible capacity and the coulombic efficiency observed after 60 cycles were about 530 mAh/g and 96%, respectively. Whatever the alloys, SEM investigations performed before and after cycling do not reveal any significant difference between the original material and the cycled material, indicating a good stability of the electrodeposited films upon cycling.  相似文献   
166.
Photoluminescence of antimony-activated potassium chloride prepared by a mechanical grinding method has been reported. The non-coincidence of the excitation and diffuse absorption band has been found as a result of the peculiar nature of the mixed phosphor, which suggests the different nature of the luminescent centers present in the phosphor. This difference in the nature of the diffuse absorption spectra and excitation spectra has been attributed to the Sb3+ and Sb5+ ions in the KCl+SbCl3 host lattice. Photoluminescence intensity has been strongly enhanced by reducing the temperature to the liquid nitrogen temperature. The powder diffraction pattern obtained from the XRD analysis shows the presence of complexes over the surface.  相似文献   
167.
针对沈北地区在钻井施工中易形成键槽、缩径.地层垮塌掉块严重,导致卡钻及大段划眼的问题,研制出了高钙复合盐、KCl、聚合醚甲酸盐钻井液体系,试验表明,KCl钻井液抑制能力强,性能稳定.可以减少油层污染,防塌效果明显.而且可以达到废弃钻井液的零排放,有利于环保。聚合醚甲酸盐钻井液摩阻压耗小.热稳定性好,水力特性优良.有利于减少油层污染,提高钻井速度,大幅度降低井下复杂情况。高钙复合盐钻井液通过控制钻屑分散,抑制造浆.达到防塌和保护油气层的目的。现场应用表明,高钙复合盐、KCl、聚合醚甲酸盐钻井液体系抑制能力强,性能稳定,具有明显的防塌效果。沈北区应用高钙复合盐、KCl、聚合醚甲酸盐钻井液体系钻探9口井,均无井下事故发生,起下钻顺利,完井电测一次成功率达到100%,中完电测成功率达到87.3%,钻井周期平均缩短28.36d,获得了良好的经济效益。  相似文献   
168.
通过对钾盐镀锌生产中电流开不大,镀层易烧焦、灰暗等生产故障实例的分析,指出了钾盐镀锌生产中设备和工艺故障均会造成这一现象的产生。将其中的工艺故障分为六个种类,介绍了故障原因的查找方法和故障处理方法,总结了钾盐镀锌生产线预防同类故障发生的技术措施和故障判别经验。  相似文献   
169.
利用自行设计的往复式磨损试验机研究丁腈橡胶在含砂KCl溶液和蒸馏水2种介质中的摩擦磨损行为,并利用场发射扫描电镜对橡胶磨痕的表面形貌及元素含量进行分析。结果表明:在2种介质中,随着载荷的增加,丁腈橡胶的摩擦因数降低而磨损量增加,但在含砂的KCl溶液介质中摩擦因数和磨损量的变化程度均高于在含砂蒸馏水介质中。丁腈橡胶在含砂KCl溶液的磨损机制为腐蚀磨损以及磨粒滑动侵蚀,在含砂蒸馏水中的磨损机制为湿磨粒磨损。K+使得丁腈橡胶表层及亚表层分子链更容易断裂,进而生成了分子量和分散性都低的产物和小分子单体,以及新的支联网状结构。  相似文献   
170.
《分离科学与技术》2012,47(5):705-714
Abstract

To evaluate its ability to remove phenol from aqueous solution, Jordanian “spent” oil shale, an abundant natural resource, has been used in an experimental adsorption study. Equilibrium of the system has been determined at three temperatures: 30, 40, and 55C. The resulting experimental equilibrium isotherms are well represented by Frendlich, Langmuir, and Redlich-Peterson isotherms. The relevant parameters for these isotherms, as regressed from the experimental equilibrium data, are presented. Effects of solution pH (in the range of 3–11), in addition to effects of three inorganic salts (KI, KCl, and NaCl, each at 0.1, 0.01, and 0.005 M), on the equilibrium isotherms have been experimentally investigated. The effects of pH in the presence of KI and NaCl were also investigated for a possible interaction between salts and solution pH. The initial concentration of phenol in the aqueous system studied ranges from 10 to 200 ppm. Experimental results show that while an acidic solution has no effect on the adsorption capacity of spent oil shale to phenol, a highly basic solution reduces its adsorbability. No sound effect was observed for the inorganic salts studied on the adsorption of phenol on spent oil shale. The experimental results show that there is no interaction between the pH of solution and the presence of salts. In spite of its ability to remove phenol, spent oil shale showed a very low equilibrium capacity (of an order of magnitude of 1 mg/g). Should the adsorption capacity of the shale be improved (by different treatment processes, such as grafting, surface conditioning), results of this study will find a direct practical implication in serving as “raw” reference data for comparison purposes. salts. The experimental results show that there is a certain degree of coupling between the pH of a solution and the presence of KI salt. Other salts have shown no interaction with the solution pH. The experimental results are explained in terms of the degree of ionization of the adsorbate which is controlled by the pH of the solution.  相似文献   
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