基于MICP的固化粉尘微生物抑尘剂试验研究

为降低露天煤矿排土场粉尘浓度,减轻和防止粉尘危害。基于微生物诱导碳酸钙沉淀(MICP)固化粉尘技术,探究了环境因素(温度、pH)对巴氏芽孢杆菌生长的影响,通过测定CaCO₃的产量来评估细菌浓度、胶结液浓度和营养液浓度对固化效果的影响;通过设计正交试验,采用矩阵分析法对巴氏芽孢杆菌微生物抑尘剂配比进行优化,提出1种新型高效、环保矿用微生物抑尘剂。结果表明：巴氏芽孢杆菌的最佳培养条件为30～35℃、pH7.5左右,微生物抑尘剂适用于偏高温、中碱性环境下的露天煤矿;微生物诱导碳酸钙沉淀过程CaCO₃的生成量与营养物质浓度和菌液浓度呈正相关关系,CaCO₃的生成量随胶结液浓度(尿素、氯化钙)增大呈现先增大后减小的趋势;巴氏芽孢杆菌微生物抑尘剂具有良好的渗透性、抗强风、保水、抗雨淋等综合性能,巴氏芽孢杆菌微生物抑尘剂成分配比优化方案为：巴氏芽孢杆菌菌液OD600值为1,胶结液(尿素、氯化钙混合溶液)取0.5 mol/L,营养物质溶液取2 g/L。     

微生物诱导碳酸钙沉淀对土壤中Pb污染稳定化的效果研究

为研究微生物修复在土壤中的适用情况，以实验室模拟巴氏芽孢杆菌（Bacillus pasteuris）诱导碳酸钙共沉淀（Microbilly induced calcite precipitation，MICP）稳定化土壤中的Pb。结果表明，采用MICP技术对土壤pH值、电导率及有机物含量等基础理化性质有很大的影响。土壤中 Pb的浸出率最高下降76.34%，重金属Pb有效态的比例下降了41.64%，Pb的碳酸盐结合态的含量最高升高13.24%。同时通过SEM和XRD分析，可以观察到土壤中Pb与碳酸钙共沉淀附着在土壤颗粒表面而被固定下来。因此，MICP技术是一种具有应用前景的土壤中Pb污染的修复技术方法。     

湘南1号深钻复杂地层护壁技术

孔壁稳定性是钻孔顺利钻进的重要条件，合理的护壁工艺可有效地保持孔壁稳定，尤其是复杂地层钻进过程中更是需要采用适合的护壁工艺来保持孔壁稳定以达到顺利钻进的目的。湘南1号深钻施工过程中多个孔段地层极为破碎，出现了严重孔壁失稳问题。通过分析地层及现场施工工艺后，针对不同孔段，形成了一套系统的护壁方案。通过现场实际护壁效果对比发现，冲洗液在轻微漏失工况下的护壁效果较好；跟管钻进工艺适合于快速穿越局部极破碎地层；水泥球混合水泥浆对极度破碎地层护壁有良好的效果。不同的护壁工艺各有优缺点，在实际钻探过程中针对性的选用高效护壁工艺对提高钻进效率有着重要意义。     

NBPT优化微生物固化尾砂效果的试验研究

为解决微生物诱导碳酸钙沉积(MICP)过程中碳酸钙分布不均匀的问题,使用脲酶抑制剂NBPT优化MICP,即在微生物注浆加固过程中短期抑制目标区域生成CaCO3的速率,使试样内CaCO3的分布更均匀。与未加NBPT的试样对比,当添加1%的NBPT时,巴氏芽孢杆菌生长迟滞期延长了8h;当抑制剂含量为1.5%、3%时,生长迟滞期分别延长了20h、48h。微生物注浆加固过程中添加NBPT后,黏聚力和内摩擦角分别提升了8.22%和4.10%。     

干热岩用耐高温钻井液关键技术及进展

干热岩(HDR)是一种可再生绿色清洁能源,其勘探开发具有埋藏深,地层破碎,压力异常,井温梯度高,孔底温度高(通常大于200℃)等特点,在钻井过程中易出现钻井液漏失量大,孔壁失稳掉块卡钻等问题。本文通过分析干热岩耐高温钻井液关键技术难点:处理剂及体系抗温问题、起泡问题、漏失、井壁失稳等问题。同时通过对国内外目前干热岩用耐高温钻井液体系进展及应用情况介绍,开展干热岩钻探耐高温钻井液技术发展方向研究,以期对推动我国干热岩资源勘探开发提供有效的技术支撑。     

金川矿区复杂地层钻探孔壁失稳机理与对策研究

金川矿区目前资源开采逐渐向深部转移，采用的主要探矿方式为在采矿巷道中布设中深钻孔，由于矿区地质条件复杂，常出现钻孔垮孔、造浆、地层涌水、破碎等情况，影响了勘察效率。为了解矿区复杂地层影响钻孔孔壁稳定性的原因，对从矿区采取的岩样进行理化分析、微观分析和力学性质分析，结果表明金川矿区钻孔孔壁失稳主要是因为钻探过程中遇强水敏性、强破碎、强涌水和高地应力地层。通过对矿区钻孔孔壁进行稳定性评价，从冲洗液技术和工程技术等方面制定了钻探技术对策，为矿区钻探施工提供了技术支撑。     

石阡县CK6地热井钻井液技术

石阡县CK6地热井钻孔地质条件复杂,630m以浅地层水敏性强,易发生缩径卡钻和地层造浆;998m和1514m处先后钻遇2个断层破碎带,地层极度破碎,钻进时坍塌、掉块、缩径事故频发,施工难度极大。为有效解决上述问题,在分析钻孔地质情况和钻井液技术难点的基础上,总结了钻井液技术要求,选择了钻井液添加剂,进行了配方实验,选出了最适配方,合理设计了钻井液方案并进行了现场应用。该钻井液方案的使用,稳定了孔壁,减少了事故率,提高了钻进效率,达到了预期效果。     

云南东川播卡矿区复杂地层泥浆技术的应用

从复杂地层岩芯钻探施工的孔壁失稳、钻孔漏失等影响因素出发,提出了复杂地层岩芯钻探中孔壁稳定及漏失的防治措施,并应用于云南东川播卡矿区的复杂地层钻探施工,为该区域或类似地层条件下的岩芯钻探的泥浆技术提供借鉴作用。     

安龙县ZK2地热井钻井液应用实践

针对安龙县ZK2地热井钻探施工中钻遇复杂地层、钻进困难的问题,综合分析了地层的特征和复杂程度。探索了适合该地层的钻井液技术,并进行了成功应用。表明所采用的钻井液性能良好,适应性强,粘度适中,滤失量合理,对防止孔壁的掉块、缩径垮塌起到了良好的抑制作用,减少了孔内事故发生率,从而提高了钻进效率。     

汶川地震断裂带科学钻探项目WFSD-2孔钻井液工艺研究

汶川地震断裂带科学钻探项目二号孔（WFSD-2）,地质条件极为复杂,孔壁稳定性差。施工期间由于地层中水敏性矿物吸水膨胀、地层破碎及地应力释放等原因,多次发生孔壁缩径、坍塌掉块及漏失现象。针对以上问题,施工中采用了以低粘增效粉和改性沥青为主要原料的LBM-GLA钻井液体系,通过对钻井液配方、性能参数的合理调整与维护以及固相等方面的控制与处理,较好地解决了上述问题。重点介绍了WFSD-2孔各孔段钻井液的使用及维护情况。     

Microbial Growth and Action: Implications for Passive Bioremediation of Acid Mine Drainage

Abstract.  Due to the variable environmental nature of mine water, several species of bacteria are important in the generation of acid mine drainage (AMD) and in bioremediation treatment technology. Enzymatic metal transport and transformation allow bacteria to survive in high-metal environments and to oxidize, reduce, and exude metals. For example, the enzymes Cr (VI) reductase and cytochrome-c3 hydrogenase allow Pseudomonas sp. to reduce Cr (VI) to less toxic Cr (III). Much more toxic organomercuric compounds are transformed by Pseudomonas fluorescens and Escherichia coli, using the enzymes organomercurial lyase and mercuric reductase. The role of bacteria in the AMD environment is not yet fully understood and consequently researchers should pay attention in this field.     

Ba/Fe双掺LaCoO3热敏陶瓷材料低温离子传输机制研究

为了开发电学性能优异的深低温材料,采用传统高温固态法制备了Ba/Fe双掺杂的LaCoO₃负温度系数热敏陶瓷材料,结合XRD、SEM、XPS等测试手段,研究了材料的物相结构、微观形貌、离子价态分布等,并在22—80 K和80—290 K范围内进行了低温电学性能测试。结果表明：双掺杂改性降低了LaCoO₃材料的应用温区,ρ（22 K）在1.85×10⁵—6.94×10⁶ Ω·cm范围内变化,材料常数B（22—100 K）在146.09—162.75 K范围内变化;在深低温环境下,材料的导电机理由80 K以上时的小极化子跳跃导电转变为80 K以下时的双交换导电,导致了材料常数B发生突变。由此证明,该双掺杂热敏陶瓷材料在极低温测试中具有可开发的应用潜力。     

Cell Pathology and Developmental Effects of Mine Waste Contamination on Invertebrates and Fish in the Methow River, Okanogan County, Washington (USA)

Abstract.  A study of the effects of mine waste on Methow River habitat in the north Cascade Mountains in the state of Washington, U.S.A. revealed impacts of sediment metal contamination on invertebrates and fish. The objectives were to determine: (1) effects of metal contamination on the growth and development of caddisfly larvae (Ecclesomyia spp.) and trout (Oncorhynchus mykiss), (2) whether in vivo exposure of caddisfly larvae in microcosms to metal contaminants induces nuclear apoptosis and the formation of electron-dense granules in gut epithelial cell mitochondria, (3) whether in situ exposure of trout and caddisfly larvae to sediment metal contamination induces nuclear apoptosis and the formation of electron-dense granules in mitochondria of gut epithelial cells and hepatocytes, and (4) whether the composition of the mitochondrial granules reflects sediment metal contamination. Electron microscopy was used to detect the cytotoxic effects of metal contamination. An above-and-below-mine approach was used to compare exposed and reference populations. Copper contamination in sediments was associated with effects on trout and caddisfly larvae at the cellular level and with secondary effects related to reduced body weights and delayed development occurring at higher levels of biological organization. Electron dense granules in the mitochondria of exposed caddisfly and trout mitochondria were detected. Elemental analysis of mitochondrial granules by X-ray analysis suggested Cu was being sequestered by mechanisms that normally regulate transient cell Ca concentrations. Chromatin compaction, margination, and the observation that large vesicles with bi-layer membranes were being expelled from the nuclei of affected cells suggest that apoptosis was also occurring.     

Adaptation of Acidithiobacillus ferrooxidans to high grade sphalerite concentrate

In this study different strategies were employed for adapting Acidithiobacillus ferrooxidans cells to both Zn²⁺ ions and high grade sphalerite concentrate. The serial subculturing was found to be a very efficient strategy for adapting A. ferrooxidans cells to higher Zn²⁺ concentrations, as well as high grade sphalerite concentrate, provided that a suitable protocol was employed. Adaptation of A. ferrooxidans cells to 30 g/L Zn²⁺ significantly enhanced the rate of bioleaching of Zn²⁺ from high grade sphalerite concentrate. Preadaptation to Zn²⁺ ion also shortened the time required to adapt the cells to the concentrate. A. ferrooxidans PTCC 1642, exhibited a higher rate of Zn²⁺ bioleaching from high grade sphalerite concentrate compared to A. ferrooxidans DSMZ 583; however, due to the adaptation protocol employed the difference in performance of the two strains was not very great. Based on the results obtained in this study suggestions were given for the mechanisms during the adaptation of A. ferrooxidans cells to high grade sphalerite concentrate.     

低反射MXene基电磁屏蔽材料的研究进展

随着通信技术和移动电子设备的不断发展，电磁干扰问题变得日益严重，因此开发高性能的电磁屏蔽材料成为了重要的研究方向。二维过渡金属碳（氮）化物（MXenes）因具有导电性高、介电常数大等优点而被广泛应用于电磁屏蔽的研究。然而，高导电性表面会导致电磁波的反射，从而造成严重的电磁波二次污染，因此研究开发低反射的MXene基电磁屏蔽材料变得非常重要。对MXene的结构特点和制备方法进行了总结，详细阐述了低反射的Ti₃C₂T_x薄膜和气凝胶电磁屏蔽材料的研究进展，展望了MXene基电磁屏蔽材料的未来研究方向和发展趋势。     

Evaluation of equilibrium, kinetic and thermodynamic parameters for biosorption of nickel(II) ions onto bacteria strain, Rhodococcus opacus

The present study explores the ability of Rhodococcus opacus bacteria strain for the removal of nickel(II) under different experimental conditions. The effects of relevant parameters such as solution pH, biomass loading, ionic strength, and temperature on nickel(II) biosorption capacity were evaluated. Although the tests were carried out using synthetic solutions, the results are representative of typical waste effluents from chemical, dyestuffs, battery manufacture, porcelain enameling, metallurgical industries and electroplating circuits. The sorption data followed the Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, and Sips isotherms. The maximum sorption capacity was found to be 7.63 mg g⁻¹ at pH 5. Thermodynamic parameters have also been evaluated and the results show that the sorption process was spontaneous and endothermic in nature. The dynamics of the sorption process were studied and the values of rate constants for different kinetic models were calculated. The activation energy of biosorption (E_a) was determined as 12.56 kJ mol⁻¹ using the Arrhenius equation.     

有机/无机杂化钙钛矿太阳能电池S形电流扭结的集总参数等效电路模型

提出一种改进的太阳能电池集总参数等效电路模型,可以实现对S形电流电压曲线的准确拟合。该改进模型使用四个二极管,采用分区和Lambert W函数方法建立结点电压显式算法,获得电流-电压显式方程。与具有多个子电路的电路模型比较,改进模型中加入分流电阻,结构上更加完整。此外,该模型可以描述S形曲线,对较大正向电压下I-V特性第一象限的指数型曲线可实现良好拟合。基于该模型解析求解算法,可避免长时间数值迭代计算,获得满足误差要求的计算结果,利于仿真电路和模型参数提取。     

Assessment of Metal Attenuation in a Natural Wetland System Impacted by Alkaline Mine Tailings,Cobalt, Ontario,Canada

A natural wetland in the Farr Creek drainage basin near Cobalt, Ontario was studied because its floor is covered with alkaline mine tailings that contain elevated levels of metals, including As, Co, Cu, and Zn, due to mining that occurred intermittently from 1904 to the 1980s. Our objectives were to characterize the biogeochemical interactions occurring throughout the wetland and to assess its ability to effectively attenuate the metal contamination. We were not able to conclusively determine if this wetland is a net source or net sink for As, Co, Cu, and Zn; it is not clear whether this wetland has reached its capacity for attenuating these trace elements. Both oxidizing and reducing bacteria were quantified and found to be prevalent throughout the wetland, with similar population densities. It is likely that the presence of localized oxic zones in the root zones of Typha latifolia supported the oxidizing bacteria populations observed. The results indicate the importance of understanding the conditions in systems being used to treat mine drainage, as well as the importance of having a detailed understanding of the metals of concern in the mine waste.     

分支溜井在多分段放矿过程中的应用

多分段放矿对人员及运输设备构成较大的安全威胁。为解决此问题,以保证放矿过程的安全和满足企业生产需要,提出了施工溜井联道、叉井、刻槽等措施,对溜井进行局部改造,确保分段溜井联道与主溜矿井不直接贯通即可正常放矿,实现了同一溜井多点放矿、多分段同时使用。同时,分支溜井的应用减少了系统溜井数量,提高每条溜井的使用率,保证了放矿人员及铲运设备安全,安全效益、经济效益显著。这种放矿方法可为矿区今后的生产和同类型的矿体开采提供一定参考与指导。     

四川某氧化铜矿石选矿试验方案对比试验研究

对四川某氧化铜矿石进行了选矿试验方案对比研究,分别进行了单一浮选和硫酸浸出—置换—浮选联合流程对比研究。结果表明,硫酸浸出—置换—浮选联合流程,可获得产率4.50%、铜精矿品位44.56%、回收率94.59%铜精矿,尾矿含铜0.12%,损失率仅为5.41%较好指标。