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Support failure of a high-stress soft-rock roadway in deep coal mine and the equalized yielding support technology： a case study

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International Journal of Coal Science & Technology 2015年第4期2卷 279-286页

作者： Lihui Sun College of resource Hebei University of EngineeringHandan 056038 China Collaborative Innovation center of the ComprehensiveDevelopment and Utilization of Coal resource Handan 056038 China

Abstract There are many soft-rock roadway coal mines in China. The surrounding rocks of the high-stress soft-rock roadways in deep mine are especially difficult to be supported using the traditional supporting way. In this study, the south wing rail roadway on the second level of Yunjialing coal mine in China was used as an example to analyze the deformation and failure characteristics and influencing factors of roadway. On this basis, this study proposed the equalized yielding support idea which employs the yielding rings to realize the pressure equalization on the bolts and cables in the section. To achieve this purpose, the first bolt-mesh-cable equalizing pressure yielding support was integrated with the second grouting reinforcement. The results proved that the yield rings of the bolts and cables on the spandrel of the arched roadway firstly developed yielding deformation; then the deformation extended to the vault of the roadway; the bolts and cables achieved a yielding extreme value of 15 and 18 tonnes, respectively. The roadway surrounding rock tended to be stable at the 26th day after the maintenance. The equalizing pressure yielding supporting technology plays a moderate pressure-releasing and actively controlling role on the surrounding rocks in the soft-rock roadway with large deformation.

关键词： Deep-well high-stress Soft-rock roadway Equalized yielding support Grouting reinforcement

Formation cause,composition analysis and comprehensive utilization of rare earth solid wastes

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Journal of Rare Earths 2009年第6期27卷 1096-1102页

作者：许涛彭会清 resource & Environment College Wuhan University of Technology National Engineering Research center of Rare Earth Metallurgy & Functional Materials Baotou Research Institute of Rare Earths

Based on practical situation of rare earth industrial chain,production process and rare earth materials that could produce solid wastes on batch were *** cause,formation volume,composition analysis and comprehensive utilization of the solid wastes of rare earth hydrometallurgy slag,electrolysis slag,Fe-based rare earth permanent magnetic materials,Co-based rare earth permanent magnetic materials,rare earth hydrogen storage materials,rare earth polishing powders and rare earth catalysts were ...

关键词： rare earths solid wastes comprehensive utilization

Synergistic photocatalytic degradation of pyridine using precious metal supported TiO_2 with KBrO_3

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Journal of Environmental Sciences 2013年第11期25卷 2299-2305页

作者： Fei Tian Rongshu Zhu Feng Ouyang Environmental Science and Engineering Research center Harbin Institute of Technology Shenzhen Graduate School Shenzhen Key Laboratory of Water resource Utilization and Environmental Pollution Control

A series of precious metals catalysts （M/TiO/, M = Ru, Rh, Pd, Ag, Ir, Pt or Au） were prepared by a light deposition method and the synergistic photocatalytic degradations of pyridine （20 mg/L） under UV irradiation （365 nm） using M/TiO2 with electron capture agent KBrO3 have been investigated. The results show that KBrO3 has a greatly synergistic role on M/TiO2 and the photocatalytic activity of M/TiO2 is closely related to its work function. Ag could greatly enhance the activity of TiO2 due to the binding characteristics of pyridine on Ag. Under the conditions of 0.5 wt.% Ag loading, Ag/TiO2 concentration of 0.1 g/L, KlrO3 concentration of 10 mmol/L and reaction liquid pH value at 9, the pyridine can be degraded by 64% within 3 hr, doubled than TiO2 photocatalytic system. The degradation kinetics of pyridine follows first-order kinetics and k = 5.53 × 10-3 min^-1.

关键词： pyridine synergistic photocatalysis precious metal titanium dioxide potassium bromate

Optimization on selenium and arsenic conversion from copper anode slime by low-temperature alkali fusion process

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Journal of Central South University 2017年第7期24卷 1537-1543页

作者： GUO Xue-yi XU Zhi-peng TIAN Qing-hua LI Dong School of Metallurgy and Environment Central South UniversityChangsha 410083China Hunan Engineering Research center of Nonferrous Metals resource Recycling Changsha 410083China

A process was proposed to convert and separate selenium and arsenic in copper anode slime(CAS) by low-temperature alkali fusion *** composite design was employed to optimize the effective parameters,in which Na OH/CAS mass ratio,fusion temperature and fusion time were selected as variables,and the conversion ratio of selenium and arsenic as ***-order polynomial models of high significance and 3D response surface plots were constructed to show the relationship between the responses and the *** area of >90% selenium conversion ratio and >90% arsenic conversion ratio was obtained by the overlaid contours at Na OH/CAS mass ratio of 0.65-0.75,fusion temperature of 803-823 K and fusion time of 20-30 *** models are validated by experiments in the optimum area,and the results demonstrate that these models are reliable and accurate in predicting the fusion process.

关键词： optimization low-temperature alkali fusion copper anode slime selenium arsenic central composite design

Recyclable thiol-modified Zr-based MOFs/hydrogel composite beads for effective removal of Hg(Ⅱ)

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Progress in Natural Science:Materials International 2023年第5期33卷 644-651页

作者： Xuechun Wang Zeming Dai Xuan Zhou Hao Chen Yu Cao Jianhua Hou Xiaozhi Wang College of Environmental Science and Engineering Yangzhou University Jiangsu Collaborative Innovation center for Solid Organic Waste resource Utilization Institutes of Agricultural Science and Technology Development

In general, majority of MOFs are powder, which limit their applications. In this study, the highly stable Zr-based MOF-808 and its thiol-modified MOF-808-SH were selected as precursors, and then they were wrapped by sodium alginate hydrogel via a dripping strategy. Based on these, MOF/hydrogel composite beads(Alg-MOF-808, AlgMOF-808-SH) with 3D network structure were prepared successfully. Due to its excellent adsorption properties and easy recovery, they were employed as effective environmental functional materials for the adsorption of Hg(Ⅱ). The adsorption capacities of Hg(Ⅱ) were 170.52 mg·g-1and 221.73 mg·g-1respectively and they can achieve adsorption equilibrium in a short time. The adsorption stability of Alg-MOF-808-SH was studied at different p H as well. In addition, the removal efficiency of composite beads for Hg(Ⅱ) was almost unaffected by other coexisting ions, displaying good adsorption selectivity. Furthermore, the removal efficiency only decreased by 10.4% after 5 cycles, indicating that the as-prepared materials have high recycling efficiency. The results demonstrated that the MOF/hydrogel composite beads have a certain application potential for mercury removal in actual wastewater.

关键词： Environmental functional material Hg (II) adsorption MOF-808 thiol groups Beads

Characterization of electrode fouling during electrochemical oxidation of phenolic pollutant

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 99-108页

作者： Xuefeng Liu Shijie You Fang Ma Hao Zhou State Key Laboratory of Urban Water resource and Environment Harbin Institute of TechnologyHarbin150090China Conservation center Shanghai MuseumShanghai200231China

Electrode fouling is a problem that commonly occurs during electro-oxidation water *** study focused on identifying the fouling behavior of Pt electrode associated with the formation of polymeric layer during electro-oxidation of *** in situ electrochemical measurements and non-destructive observation of the electrode morphology were *** results demonstrated that the electrode fouling was highly dependent on thermodynamic process of electrode that was controlled by anode *** anode potential lower than 1.0 V vs SHE,the direct electro-oxidation caused the electrode fouling by the formation of polymeric *** fouling layer decreased the electrochemically active surface area from 8.38 cm^(2)to 1.57 cm^(2),indicated by the formation of polymeric film with thickness of 2.3µm,increase in mass growing at a rate of 3.26µg/cm^(2)/*** degree to which the anode was fouled was independent of anion in the *** comparison,at anode potential higher than 2.7 V vs SHE,the anions(e.g.,chloride)could exert a major influence to the behavior of electrode *** presence of chloride was shown to mitigate the fouling of electrode significantly through preventing the formation of polymeric film by active chlorine(e.g.,Cl•and Cl_(2))produced from anodic oxidation of *** chloride is the most abundant anionic species existing in both natural and engineered water system,this study not only offers a deep insight into the mechanism of electrode fouling,but also suggests strategies for anti-fouling in the presence of chloride in electro-oxidation process.

关键词： Electro-oxidation Electrode fouling Polymeric film Chloride ions

Carboniferous–Permian marine transgressions in the Jiyang Depression

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International Journal of Mining Science and Technology 2014年第1期24卷 87-92页

作者： Zhang Kuihua Chen Shiyue Zhang Guanlong Department of Earth resource and Information China University of Petroleum Qingdao Western New Prospect Research center Shengli Oilfield

In recent years, great attention has been paid to oil and gas exploration in the Carboniferous-Permian strata of the Bohaiwan basin, especially the Carboniferous-Permian marine transgression, using data from drilling, outcrops and carbonate acid-insoluble residue experiments together with the tectonic evo- lutionary history of the peripheral orogenic zones of the North China plate and the Tan-Lu fault zones. The .＇;tudy concludes that marine transgressions took place on six occasions during Carboniferous-Perm- ian time in the Jiyang Depression. The marine transgressions were concentrated in the Late Carbonifer- ous： two marine transgressions occurred in the early Late Carboniferous, and the scale of the first was smaller and the time was shorter than those of the second. The other four marine transgressions hap- pened in the late Late Carboniferous, the first and the fourth of which were larger in scale and longer in time than the second and the third. The seawater came from the Jiaobei area, the eastward part of the Qinling-Dabie residual sea basin, and invaded progressively as a planar flow from south to north and from east to west. These findings have great significance for thorough analysis of the sedimentary characteristics and evolution of the Carboniferous-Permian strata in the livang Denression.

关键词： Carboniferous-PermianMarine transgression North China plate Tan-Lu fault zone Jiyang Depression

Superior adsorption performance of graphitic carbon nitride nanosheets for both cationic and anionic heavy metals from wastewater

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Chinese Journal of Chemical Engineering 2019年第2期27卷 305-313页

作者： Gang Xiao Yaoqiang Wang Shengnan Xu Peifeng Li Chen Yang Yu Jin Qiufeng Sun Haijia Su State Key Laboratory of Chemical resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and Engineering (BAIC-SM) Beijing University of Chemical Technology

Water pollution caused by highly toxic Cd(II), Pb(II), and Cr(VI) is a serious problem. In the present work,a green and low-cost adsorbent of g-C_3N_4 nanosheets was developed with superior capacity for both cationic and anionic heavy metals. The adsorbent was easily fabricated through one-step calcination of guanidine hydrochloride with thickness less than 1.6 nm and specific surface area of 111.2 m^2·g^(-1). Kinetic and isotherm studies suggest that the adsorption is an endothermic chemisorption process, occurring on the energetically heterogeneous surface based on a hybrid mechanism of multilayer and monolayer adsorption. The tri-s-triazine units and surface N-containing groups of g-C_3N_4 nanosheets are proposed to be responsible for the adsorption *** study on pH demonstrates that electrostatic interaction plays an important role. The maximum adsorption capacity of Cd(II), Pb(II), and Cr(VI) on g-C_3N_4 nanosheets is 123.205 mg·g^(-1), 136.571 mg·g^(-1),and 684.451 mg·g^(-1), respectively. The better adsorption performance of the adsorbent than that of the recently reported nanomaterials and low-cost adsorbents proves its great application potential in the removal of heavy metal contaminants from wastewater. The present paper developed a promising adsorbent which will certainly find applications in wastewater treatment and also provides guiding significance in designing adsorption processes.

关键词： g-C3N4 nanosheets Nanomaterials Adsorption Heavy metals Wastewater

Geranylgeranyl pyrophosphate-mediated protein geranylgeranylation regulates endothelial cell proliferation and apoptosis during vasculogenesis in mouse embryo

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Journal of Genetics and Genomics 2021年第4期48卷 300-311页

作者： Danyang Chong Zhong Chen Shan Guan Tongyu Zhang Na Xu Yue Zhao Chaojun Li Ministry of Education Key Laboratory of Model Animals for Disease Study Model Animal Research Center and School of MedicineNanjing UniversityNational Resource Center for Mutant MiceNanjing 210093China

Vascular development is essential for the establishment of the circulatory system during embryonic development and requires the proliferation of endothelial ***,the underpinning regulatory mechanisms are not well ***,we report that geranylgeranyl pyrophosphate(GGPP),a metabolite involved in protein geranylgeranylation,plays an indispensable role in embryonic vascular *** is synthesized by geranylgeranyl pyrophosphate synthase(GGPPS)in the mevalonate *** selective knockout of Ggpps in endothelial cells led to aberrant vascular development and embryonic lethality,resulting from the decreased proliferation and enhanced apoptosis of endothelial cells during *** defect in protein geranylgeranylation induced by GGPP depletion inhibited the membrane localization of Rho A and enhanced yes-associated protein(YAP)phosphorylation,thereby prohibiting the entry of YAP into the nucleus and the expression of YAP target genes related to cell proliferation and the antiapoptosis ***,inhibition of the mevalonate pathway by simvastatin induced endothelial cell proliferation defects and apoptosis,which were ameliorated by ***(GGOH),a precursor of GGPP,ameliorated the harmful effects of simvastatin on vascular development of developing fetuses in pregnant *** results indicate that GGPP-mediated protein geranylgeranylation is essential for endothelial cell proliferation and the antiapoptosis process during embryonic vascular development.

关键词： GGPP Protein geranylgeranylation Endothelial cell Proliferation Apoptosis