用不同能量γ光子全能峰相对效率曲线和KCI测定^24Na活度方法的研究

研究了利用NaI(φ76 mm×76 mm)探测器不同能量γ光子的全能峰相对效率曲线和分析纯KCl测量水溶液中24Na活度的方法.所谓相对效率是指不同能量对某一能量全能峰计数效率的归一值.这种方法不需要用活度精确已知的任何核素的标准溶液进行刻度.相对效率曲线的建立是将不同能量γ光子的相对效率与能量E的关系用最小二乘法拟合成一个函数f(E)=A+BE+CE2+DE3+UE4.这些γ能量(以MeV为单位)包括56Mn的0.8468、1.8108、2.113,27Mg的0.8438、1.0144,82Br的1.0439、1.3175、1.4748,以及38Cl的1.6422和2.1676.放射性核素都是利用一个约为130μg的252Cf中子源活化产生.本方法的原理可用于非24Na其他放射性核素溶液的活度测量,并且更适合于Ge探测器.当用Ge探测器时,仅用82Br的各种γ光子能量就能确定全能峰相对效率曲线.     

NH4Cl/KCl添加剂对铝粉氮化反应的影响

研究了NH4Cl／KCl添加剂对铝粉氮化反应的影响。运用TG／DSC考察了Al粉、Al NH4Cl和Al NH4Cl／KCl等前驱体粉末的氮化过程，运用XRD、SEM、XRF对氮化产物进行了表征。研究结果表明：NH4Cl能降低氮化温度，避免铝粉发生熔化和结块，保证得到纳米尺度的AlN颗粒；KCl的蒸发则可以破坏铝粉表面的氮化膜，促进铝粉的完全氮化，且只有两种同时作为添加剂使用，才能实现铝粉的完全氮化，用氨气做为反应气体可以消除因添加剂引入水分杂质的影响。NH4Cl／KCl还是一种低残留的添加剂，可以用来制备高纯度的AlN。     

Adsorption of Phenol from Aqueous Systems onto Spent Oil Shale

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.     

东胜气田钻井液废弃物处理与钻井液技术

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。     

Membrane behavior of bentonite-amended compacted clay

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.     

卡拉胶与氯化钾用量对中性奶冻品质影响研究

研究了卡拉胶与氯化钾用量对奶冻品质的影响,以粒度分布、质构特性、微观结构与析水率等为分析检测指标。研究结果表明:当卡拉胶用量小于0.10%时,硬度低,凝胶结构差;当卡拉胶用量增至0.15%以上时,硬度适当,凝胶结构较好,但从粒度分布与显微结构判断,体系开始出现絮凝。同时,氯化钾促进凝胶,而高含量的氯化钾有诱导体系失稳絮凝的趋势,在卡拉胶用量0.20%时,影响更为显著,且此时析水率也随之增加。综合考虑,以卡拉胶0.15%用量与氯化钾0.01%用量下奶冻具有良好的质构品质。     

部分KCl替代NaCl对强化高温成熟工艺干腌火腿肌肉色泽形成的影响

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)。     

KCl部分替代NaCl对宣威火腿细菌多样性的影响

为探究KCl部分替代NaCl腌制的宣威火腿中细菌多样性和群落结构,以100% NaCl腌制的宣威火腿为对照组,分别以KCl替代30%、40%、50%和60% NaCl进行腌制作为实验组,基于Illumina MiSeq高通量测序技术对火腿表面和内部细菌16S rRNA的V3～V4区进行扩增和测序,进而比较不同KCl替代比例宣威火腿微生物的群落结构组成及多样性差异。结果表明：不同KCl替代组火腿表面共得到257 777 条序列和6 153 个操作分类单元,在火腿内部共得到248 102 条序列和5 704 个操作分类单元;尽管不同KCl替代组的火腿在微生物丰度上存在一定差异,但各KCl替代组火腿表面和内部样本在门水平上的优势菌群均为变形菌门和厚壁菌门,KCl部分替代NaCl使火腿表面和内部变形菌门的相对丰度增加,均在40% KCl替代组中最高,且显著高于对照组（P＜0.05）;不同KCl替代比例腌制的宣威火腿细菌群落结构存在较大相似性,但在一定程度上降低了火腿表面菌群丰度和群落多样性,内部菌群丰度和群落多样性则无显著差异。     

KCl部分替代NaCl对干腌火腿工艺过程中蛋白质水解的影响

为了降低干腌火腿钠含量,应用40%KCl替代Na Cl对火腿原料进行腌制,采用强化高温成熟现代工艺制备干腌火腿,分析加工过程中火腿股二头肌盐分含量、水分含量、p H、蛋白水解指数、肽氮和氨态氮含量,研究KCl替代对火腿加工过程中组织蛋白酶B和L潜在酶活力变化的影响。结果表明:40%KCl替代Na Cl对火腿中组织蛋白酶B和L潜在酶活力变化无显著影响(p>0.05),风干成熟产品理化指标、蛋白水解指数、肽氮和氨态氮含量等无显著差异(p>0.05),说明采用40%KCl替代Na Cl对干腌火腿的蛋白质降解过程无显著影响(p>0.05)。      

Increasing Oil Concentration Affects Consumer Perception and Physical Properties of Mayonnaise‐type Spreads Containing KCl

Reducing sodium intakes remains a global challenge for the food industry. KCl is a potential salt substitute but imparts bitterness when used at high concentrations. Little is known about how oil concentrations (OC) affect consumers’ perception of saltiness and bitterness in emulsion products such as mayonnaise containing KCl. We evaluated consumers’ perception and physical properties of mayonnaise‐type spreads at various oil and tastant (NaCl or KCl) concentrations. Consumers (N = 306) evaluated saltiness, bitterness, overall taste liking (OTL) and purchase intent (PI). Viscosity, pH, water activity, and consistency/texture were also measured. Oil and tastant (NaCl or KCl) concentrations had significant effects on saltiness, viscosity, and pH. As OC increased, saltiness intensity slightly decreased for spreads. Increasing oil concentration increased viscosity. Generally, spreads containing KCl had higher bitterness and pH than spreads containing NaCl. All spreads containing KCl were penalized for being “too bitter.” PI was affected by OTL for all spreads but OC was also a significant factor in the purchase decision of spreads containing NaCl. This study demonstrated that increasing OC affected consumers’ taste perception (saltiness and bitterness) and spreads’ physical properties including pH and viscosity.