乳状液膜法萃取废水中氰化物的特性

针对氰化废水的特点,以三正辛胺（TOA）为载体、煤油为膜溶剂、液体石蜡为膜助剂、NaOH水溶液为内水相,采用乳状液膜技术处理工业废水中的氰化物。重点考察了表面活性剂用量、流动载体用量、内相液NaOH浓度等因素对氰化物萃取率的影响规律。研究结果表明：当TOA体积分数为2%、表面活性剂Span-80体积分数为3%、液体石蜡体积分数为1%、内水相NaOH质量分数为2%、油内比为1︰1、乳水比为1︰7、萃取时间为15min时,氰化废水中氰化物的萃取率达到95%以上。在实验得出的最优条件下,考察最优条件对初始浓度不同的实际废水的适用范围,分别对初始浓度为322.23mg/L、483.35mg/L、644.46mg/L和966.70mg/L的氰化废水进行处理,可得该体系下处理氰化废水的较佳的浓度范围为300～500mg/L,氰化废水中氰化物的萃取率可达到95%以上。综上所述,乳状液膜法在工业上具有良好的应用前景。     

Examining natural rock varnish and weathering rinds with laser-induced breakdown spectroscopy for application to ChemCam on Mars

A laser-induced breakdown spectroscopy (LIBS) instrument is traveling to Mars as part of ChemCam on the Mars Science Laboratory rover. Martian rocks have weathered exteriors that obscure their bulk compositions. We examine weathered rocks with LIBS in a martian atmosphere to improve interpretations of ChemCam rock analyses on Mars. Profile data are analyzed using principal component analysis, and coatings and rinds are examined using scanning electron microscopy and electron probe microanalysis. Our results show that LIBS is sensitive to minor compositional changes with depth and correctly identifies rock type even if the series of laser pulses does not penetrate to unweathered material.     

As(V) removal from aqueous media using α-MnO2 nanorods-impregnated laterite composite adsorbents

We present a novel way of enhancing the utility of low cost readily available laterite by impregnating it with the α-MnO₂ nanorods, thus making a composite material suitable for the removal of As(V) from aqueous media. The composites were synthesized by two methods: (i) ball-milling of a physical blend of laterite with pre-synthesized MnO₂; and (ii) in situ formation of MnO₂ in the presence of laterite. The BET surface area of composites prepared by both methods was markedly higher compared to un-modified laterite, and the presence of MnO₂ in the composite was also confirmed by XRD analysis and TEM microscopy. The adsorption capacity for As(V) was found to be highly pH dependent and the adsorption kinetics followed a pseudo second-order kinetic model. The Langmuir adsorption isotherm was found to be the best model to describe the adsorption equilibrium of As(V) onto un-modified laterite as well both ball-milled and in situ formed composite. The adsorption capacities at room temperature and pH 7.0 were found to be 1.50 mg g^?1, 8.93 mg g^?1 and 9.70 mg g^?1, for un-modified laterite, ball-milled and in situ formed composite, respectively.     

准噶尔盆地腹部侏罗系深部优质储层成因

准噶尔盆地腹部侏罗系主要发育辫状河、三角洲和湖泊等沉积相类型,其岩石类型以成分成熟度低的岩屑砂岩和长石质岩屑砂岩为主,压实作用是控制储层质量的主要成岩作用。通过铸体薄片和物性资料综合分析,认为准噶尔盆地莫索湾地区在埋深 3500～4500m 发育孔隙度和渗透率较高的优质砂岩储层带,且此深部优质储层带是原生孔隙带,而非次生溶蚀孔隙带。结合测井资料分析,认为莫索湾地区存在欠压实带,该区莫13井、莫15井、盆5井等在欠压实带均表现出高声波时差、低视电阻率等异常。该区欠压实引起的异常高压大大削弱了正常压实作用对深部地层的影响,是造成该区深部优质储层发育的主要原因。研究区欠压实砂岩储层分布具有明显规律,即砂泥比越低,泥岩层厚度越大,越容易发育欠压实砂岩储层。     

Mechanical properties of 10 mol% Sc2O3-1 mol% CeO2-89 mol% ZrO2 ceramics

The mechanical properties, such as Young's modulus, Vickers hardness, indentation fracture resistance, room and high temperature four-point bending strength and SEVNB fracture toughness along with the stress-strain deformation behavior in compression, of 10 mol% Sc₂O₃-1 mol% CeO₂-ZrO₂ (ScCeZrO₂) ceramics have been studied. The chosen composition of the ScCeZrO₂ has very high ionic conductivity and, therefore, is very promising oxygen ion conducting electrolyte for the intermediate temperature solid oxide fuel cells. Therefore, its mechanical behavior is of importance and is presented in the paper.     

改进的小波阈值在电能质量信号去噪中的应用

针对硬阈值去噪效果不佳,软阈值过度光滑使信号失真的缺点,提出了一种改进的自适应的阈值去噪方法。该算法将数理统计与信号和噪声的小波系数的分布规律和传播特点及噪声的标准差贡献率结合起来,对阈值门限进行了改进,并采用软阈值函数对信号进行处理,实现了其去噪的功能。结果表明,改进后的算法对电能质量信号进行消噪处理,信噪比增益和均方误差上均优于传统阈值算法及一些改进后的阈值算法,而且能够较好地保留电能质量信号的特征信息。     

生态空间与容量约束下城市空间增长研究 ——以贵阳市花溪区为例

综合考虑快速增长的刚性需求、提 质发展的客观要求以及山水生态环境保护 的现实条件,是确保西部山地城市健康、快 速发展需解决的关键问题。本文在分析生 态敏感性、生态承载力的研究方法及其作 用特征的基础上,设计了整合生态敏感性空 间约束、生态承载力容量约束的城市空间规 划技术方法。以贵阳市花溪区为实证,从规 模容量控制、空间格局规划以及管控指引等 方面示范了相应的技术方法,明确了其发展 规模和空间,并提出了控制要点。     

Determining suitable dimensions for dairy goat feeding places by evaluating body posture and feeding reach

Confined goats spend a substantial part of the day feeding. A poorly designed feeding place increases the risk of feeding in nonphysiological body postures, and even injury. Scientifically validated information on suitable dimensions of feeding places for loose-housed goats is almost absent from the literature. The aim of the present study was, therefore, to determine feeding place dimensions that would allow goats to feed in a species-appropriate, relaxed body posture. A total of 27 goats with a height at the withers of 62 to 80 cm were included in the study. Goats were tested individually in an experimental feeding stall that allowed the height difference between the feed table, the standing area of the forelegs, and a feeding area step (difference in height between forelegs and hind legs) to be varied. The goats accessed the feed table via a palisade feeding barrier. The feed table was equipped with recesses at varying distances to the feeding barrier (5–55 cm in 5-cm steps) at angles of 30°, 60°, 90°, 120°, or 150° (feeding angle), which were filled with the goats' preferred food. In 18 trials, balanced for order across animals, each animal underwent all possible combinations of feeding area step (3 levels: 0, 10, and 20 cm) and of difference in height between feed table and standing area of forelegs (6 levels: 0, 5, 10, 15, 20, and 25 cm). The minimum and maximum reach at which the animals could reach feed on the table with a relaxed body posture was determined for each combination. Statistical analysis was performed using mixed-effects models. The animals were able to feed with a relaxed posture when the feed table was at least 10 cm higher than the standing height of the goats' forelegs. Larger goats achieved smaller minimum reaches and minimum reach increased if the goats' head and neck were angled. Maximum reach increased with increasing height at withers and height of the feed table. The presence of a feeding area step had no influence on minimum and maximum reach. Based on these results, the goats' feeding place can be designed to ensure that the animals are able to reach all of the feed in the manger or on the feed table with a relaxed posture, thus avoiding injuries and nonphysiological stress on joints and hooves. A feeding area step up to a maximum of 20 cm need not be taken into account in terms of feeding reach. However, the feed table must be raised at least 10 cm above the standing area to allow the goats to feed in a species-appropriate, relaxed posture.     

The Ability of the Nitric Oxide Synthases Inhibitor T1023 to Selectively Protect the Non-Malignant Tissues

Previously, we showed that a nitric oxide synthase (NOS) inhibitor, compound T1023, induces transient hypoxia and prevents acute radiation syndrome (ARS) in mice. Significant efficacy (according to various tests, dose modifying factor (DMF)—1.6–1.9 against H-ARS/G-ARS) and safety in radioprotective doses (1/5–1/4 LD10) became the reason for testing its ability to prevent complications of tumor radiation therapy (RT). Research methods included studying T1023 effects on skin acute radiation reactions (RSR) in rats and mice without tumors and in tumor-bearing animals. The effects were evaluated using clinical, morphological and histological techniques as well as RTOG classification. T1023 administration prior to irradiation significantly limited the severity of acute RSR. This was due to a decrease in radiation alteration of the skin and underlying tissues, and the preservation of the functional activity of cell populations that are critical in the pathogenesis of radiation burn. The DMF values for T1023 for skin protection were 1.4–1.7. Moreover, its radioprotective effect was fully selective to normal tissues in RT models of solid tumors—T1023 reduced the severity of acute RSR and did not modify the antitumor effects of γ-radiation. The results indicate that T1023 can selectively protect the non-malignant tissues against γ-radiation due to hypoxic mechanism of action and potentiate opportunities of NOS inhibitors in RT complications prevention.     

Cystine-capped CdSe@ZnS nanocomposites: mechanochemical synthesis, properties, and the role of capping agent

Cystine-capped CdSe@ZnS nanocomposites were synthesized mechanochemically with the aim to prepare a material which could be used in medicine for biosensing applications. Although synthesized CdSe@ZnS nanocomposites were capped with l-cysteine, cystine was formed from l-cysteine during the milling process. It was proven that water plays the key role in this oxidative transformation. The novel material was characterized by the complex of physico-chemical methods (FTIR, XPS, SEM, EDX, surface area measurements) and CHNS analysis. The leakage of Cd²⁺ and Zn²⁺ ions into physiological solution was also studied.