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MUDS——实现农村广播电视有效覆盖的新途径
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作者 张帆 《中国有线电视》 2005年第13期1270-1271,共2页
关键词 广 mudS 线 线 UHF DVB mudS DMB 线
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Disposal and Treatment Methods for Pesticide Containing Wastewaters: Critical Review and Comparative Analysis 被引量:2
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作者 Mariam T. Al Hattab Abdel E. Ghaly 《Journal of Environmental Protection》 2012年第5期431-453,共23页
Pesticides provide the primary means for controlling organisms that compete with man for food and fibre or cause injury to man, livestock and crops. They played a vital role in the economic production of wide ranges o... Pesticides provide the primary means for controlling organisms that compete with man for food and fibre or cause injury to man, livestock and crops. They played a vital role in the economic production of wide ranges of vegetable, fruit, cereal, forage, fibre and oil crops which now constitute a large part of successful agricultural industry in many countries. After application to the target areas, pesticide residues are removed from applicators by rinsing with water which results in the formation of a toxic wastewater that represents a disposal problem for many farmers. Pesticides can adversely affect people, pets, livestock and wildlife in addition to the pests they are intended to destroy. The phenomenon of biomagnification of some pesticides has resulted in reproductive failure of some fish species and egg shell thinning of birds such as peregrine falcons, sparrow hawk and eagle owls. Pesticide toxicity to humans include skin and eye irritation and skin cancer. Therefore, care must be exercised in the application, disposal and treatment of pesticides. Currently, disposal of pesticide wastewater is carried out by: 1) land cultivation, 2) dumping in soil pits, plastic pits and concrete pits or on land and in extreme cases in streams near the rinsing operation, 3) use of evaporation beds and 4) land filling. These methods of disposal are unsafe as the surface run off will reach streams, rivers and lakes and the infiltration of the wastewater into the local soil will eventually reach ground water. The treatment methods currently used for pesticide wastewater include: 1) incineration (incinerators and open burning), 2) chemical treatments (O3/UV, hydrolysis, Fenton oxidation and KPEG), 3) physical treatments (inorganic, organic absorbents and activated carbon) and 4) biological treatments (composting, bioaugmentation and phytoremediation). Therefore, the choice of safe, on farm disposal techniques for agricultural pesticides is very important. A comparative analysis was performed on 18 methods of pesticide disposal/treatment using six criteria: containment, detoxification ability, cost, time, suitability for on farm use, size and evaporation efficiency. The results indicated that of the 18 methods evaluated, 9 scored above 80/100 and can be used on farm. They were organic absorbents (97), composting (94), bioaugmentation (92), inorganic absorbents (90), Fenton oxidation (86), O3/UV (83), activated carbon (82), hydrolysis (82), and land cultivation (80). The other methods are not suitable for on farm use as they suffered from containment problems, high cost and variability of effectiveness. 展开更多
关键词 Pesticides Health Soil Water disposal Treatment Land Cultivation disposal PITS Evaporation PONDS LANDFILLS Incineration O3/UV Fenton Oxidation Hydrolysis Bioremediation Bioaugmentaion
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Patients’Knowledge, Attitude and Practices on Disposal Methods of Expired and Unused Medicines: Implication for Creation of Drug Take-Back Program
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作者 Martin Kampamba Zebedy Kalambwa +7 位作者 Billy Chabalenge Janipher Zulu Steward Mudenda Tadious Chimombe Webrod Mufwambi Audrey Hamachila Mashebe Innocent Ngula Christabel Nang’andu Hikaambo 《Pharmacology & Pharmacy》 2024年第4期113-128,共16页
Background: Handling of medicines is a day-to-day activity by patients and many health care providers. However, multiple studies have brought to light inappropriate disposal methods for expired and unused medication (... Background: Handling of medicines is a day-to-day activity by patients and many health care providers. However, multiple studies have brought to light inappropriate disposal methods for expired and unused medication (EUM). Improper disposal of expired and unused medicines is hazardous both to humans and the environment. Objective: This sought to measure patients’ knowledge, attitude, and practices on disposal methods of EUM. Methods: A cross-sectional study was carried out among 384 patients at three outpatient pharmacies at the University Teaching Hospitals (UTHs). The structured questionnaire was used to collect data and STAT version 15.1 was used to analyse the data. Results: 384 respondents participated in this study and, at some point, had EUM. In this study, 356 (92.7%) of the participants reported that they had never heard of a drug take-back system. Most of the participants 285 (74.2%) and 239 (62.2%) kept and donated their unused medicine, respectively. Additionally, 244 (63.5%), 212 (55.2%), and 176 (44.8%) of the participants disposed of expired medicines in the bin or garbage, flushed them in toilets or sinks, or burned them, respectively. Occupation was significantly associated with unsafe disposal of unused medicine [P-value = 0.019]. Conclusion and Relevance: Knowledge of safe disposal methods for EUM was good amongst most participants. However, used unsafe disposal methods. The majority of the participants exhibited positive attitude concerning safe disposal methods. This study highlights the need for drug-take-back program creation in Zambia. 展开更多
关键词 ATTITUDE disposal Methods Expired Medicines KNOWLEDGE PRACTICES Unused Medicines
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Utilization of Basalt Saw Mud as a Spherical Porous Functional Aggregate for the Preparation of Ordinary Structure Concrete
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作者 周永祥 关青锋 +2 位作者 LENG Faguang WANG Jing LI Tianjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期364-375,共12页
To promote the production and application of artificial aggregates,save natural sand resources and protect the ecological environment,we evaluated the feasibility of using spherical porous functional aggregates(SPFAs)... To promote the production and application of artificial aggregates,save natural sand resources and protect the ecological environment,we evaluated the feasibility of using spherical porous functional aggregates(SPFAs) formed by basalt saw mud under autoclave curing in ordinary structural concrete.In our work,two types of prewetted functional aggregates were taken as replacements for natural aggregates with different volume substitution rates(0%,5%,10%,15%,20%,25%,and 30%) in the preparation of ordinary structural concrete with water-to-binder ratios(W/B) of 0.48 and 0.33.The effects of the functional aggregate properties and content,W/B,and curing age on the fluidity,density,mechanical properties and autogenous shrinkage of ordinary concrete were analyzed.The experimental results showed that the density of concrete declined at a rate of not more than 5%,and the 28 d compressive strength could reach 31.0-68.2 MPa.Low W/B,long curing age and high-quality functional aggregates were conducive to enhancing the mechanical properties of SPFAs concrete.Through the rolling effects,SPFAs can optimize the particle gradation of aggregate systems and improve the fluidity of concrete,and the water stored inside SPFAs provides an internal curing effect,which prolongs the cement hydration process and considerably reduces the autogenous shrinkage of concrete.SPFAs exhibits high strength and high density,as well as being more cost-effective and ecological,and is expected to be widely employed in ordinary structural concrete. 展开更多
关键词 lightweight concrete civil concrete building basalt saw mud fly ash internal curing environmentally friendly
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Managing the surge:A comprehensive review of the entire disposal framework for retired lithium-ion batteries from electric vehicles
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作者 Ruohan Guo Feng Wang +2 位作者 M.Akbar Rhamdhani Yiming Xu Weixiang Shen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期648-680,共33页
Anticipating the imminent surge of retired lithium-ion batteries(R-LIBs)from electric vehicles,the need for safe,cost-effective and environmentally friendly disposal technologies has escalated.This paper seeks to offe... Anticipating the imminent surge of retired lithium-ion batteries(R-LIBs)from electric vehicles,the need for safe,cost-effective and environmentally friendly disposal technologies has escalated.This paper seeks to offer a comprehensive overview of the entire disposal framework for R-LIBs,encompassing a broad spectrum of activities,including screening,repurposing and recycling.Firstly,we delve deeply into a thorough examination of current screening technologies,shifting the focus from a mere enumeration of screening methods to the exploration of the strategies for enhancing screening efficiency.Secondly,we outline battery repurposing with associated key factors,summarizing stationary applications and sizing methods for R-LIBs in their second life.A particular light is shed on available reconditioning solutions,demonstrating their great potential in facilitating battery safety and lifetime in repurposing scenarios and identifying their techno-economic issues.In the realm of battery recycling,we present an extensive survey of pre-treatment options and subsequent material recovery technologies.Particularly,we introduce several global leading recyclers to illustrate their industrial processes and technical intricacies.Furthermore,relevant challenges and evolving trends are investigated in pursuit of a sustainable end-of-life management and disposal framework.We hope that this study can serve as a valuable resource for researchers,industry professionals and policymakers in this field,ultimately facilitating the adoption of proper disposal practices. 展开更多
关键词 Lithium-ion battery Battery reproposing and recycling Miaieiials recovery technologies Techno-economic issues End-of-life management disposal framework
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Analysis of Calcined Red Mud Properties and Related Mortar Performances
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作者 Zhengfan Lyu Yulin Li +2 位作者 Mengmeng Fan Yan Huang Chenguang Li 《Fluid Dynamics & Materials Processing》 EI 2024年第5期901-913,共13页
Red mud(RM)is a low-activity industrial solid waste,and its utilization as a resource is currently a hot topic.In this study,the micro characteristics of red mud at different calcination temperatures were analyzed usi... Red mud(RM)is a low-activity industrial solid waste,and its utilization as a resource is currently a hot topic.In this study,the micro characteristics of red mud at different calcination temperatures were analyzed using X-ray diffraction and scanning electron microscopy.The performance of calcined red mud was determined through mortar strength tests.Results indicate that high-temperature calcination can change the mineral composition and microstructure of red mud,and increase the surface roughness and specific surface area.At the optimal temperature of 700°C,the addition of calcined red mud still leads to a decrease in mortar strength,but its activity index and flexural coefficient increase by 16.2%and 11.9%with respect to uncalcined red mud,reaching values of 0.826 and 0.974,respectively.Compared with the control group,the synergistic activation of calcined red mud with slag can increase the compressive and flexural strength of the mortar by 12.9%and 1.5%,reaching 8.7 and 62.4 MPa,respectively.Correspondingly,the activity index and flexural coefficient of the calcined RM and GGBS(Ground Granulated Blast furnace Slag)mixtures also increase to 1.015 and 1.130,respectively. 展开更多
关键词 Red mud SLAG thermal activation synergistic activation mortar test microscopic properties
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Solidification/Stabilization of Chromium in Red Mud-based Geopolymer
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作者 田崇霏 LUO Zhongtao +4 位作者 LIU Lei LIU Xiaohai 张美香 陈萌 HAI Ran 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期819-830,共12页
Up to 1.5wt%of Cr(Ⅲ)salts(CrCl_(3),and Cr_(2)O_(3))and Cr(Ⅵ)salts(Na_(2)CrO_(4),and CaCr_(2)O_(7))were incorporated into red mud-based geopolymers,respectively.The solidification/stabilization,compressive strength,a... Up to 1.5wt%of Cr(Ⅲ)salts(CrCl_(3),and Cr_(2)O_(3))and Cr(Ⅵ)salts(Na_(2)CrO_(4),and CaCr_(2)O_(7))were incorporated into red mud-based geopolymers,respectively.The solidification/stabilization,compressive strength,and durability of the Cr-containing geopolymers were investigated.The experimental results indicate that the red mud-based geopolymer could effectively solidify/stabilize different types of Cr salts with solidification/stabilization rates of above 99.61%.Geopolymers are environmentally safe when the dosage of CaCr_(2)O_(7)is≤1.0wt%,or the dosage of CrCl_(3),Cr_(2)O_(3),and Na_(2)CrO_(4)is≤1.5wt%,respectively.The effects of Cr salts on the compressive strength varies with the type and content of Cr salts.The freeze-thaw cycle is more destructive to geopolymer properties than sulfate attack or acid rain erosion.The solidification/stabilization of Cr is mainly attributed to the following reasons:a)The chemical binding of Cr is related to the formation of Cr-containing hydrates(eg,magnesiochromite((Mg,Fe)(Cr,Al)_(2)O_(4)))and doping into N-A-S-H gel and C-A-S-H gel framework;b)The physical effect is related to the encapsulation by the hydration products(e g,N-A-S-H gel and C-A-S-H gel).This study provides a reference for the treatment of hazardous Cr-containing wastes by solid waste-based geopolymers. 展开更多
关键词 CHROMIUM SOLIDIFICATION/STABILIZATION GEOPOLYMER red mud DURABILITY
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Study of the Management and Disposal Practices of Unused or Out-of-Date Medicines by Households in the Municipality of Ouagadougou, Burkina Faso
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作者 Daniel Dori Adama Guembré +2 位作者 Kampadilemba Ouoba Nicolas Méda Rasmané Semdé 《Journal of Biosciences and Medicines》 2024年第3期291-302,共12页
Introduction: Not all medicines that pass-through consumers’ hands are used, and some often expire in households. These health products can be sources of accidental risks and pollution when they are not properly disp... Introduction: Not all medicines that pass-through consumers’ hands are used, and some often expire in households. These health products can be sources of accidental risks and pollution when they are not properly disposed of. In Burkina Faso, there are as yet no guidelines for the disposal of unused medicines in households. The aim of this study was to estimate the extent of household possession of unused or expired medicines, and to describe attitudes and disposal practices. Methods: This was a descriptive cross-sectional study covering households in the Ouagadougou commune conducted from June to August 2021. Two-stage stratified sampling was used: selection of Enumeration Zones (EZs) and selection of households, with each EZ comprising several households. Data collection was based on direct interviews using a structured questionnaire. Data were processed using Epi Info software version 7.2.4.0. Results: In total, 417 household residents were surveyed out of the planned 423 households, corresponding to a completion rate of 98.58% compared with the initial sample. Among the respondents, 79.62% had unused and/or expired medicines in their household. A total of 2562 drug packaging units were counted, for a total weight of 121.90 kg. Nearly 75% were aware that improper disposal was a danger to the environment. Some respondents kept their unused medicines at home until they expired (43.41%), and disposed of them mainly by throwing them in the household garbage (75.58%). The majority (79%) were in favor of the government setting up a take-back program for these medicines. Conclusion: The introduction of a take-back program for unused or out-of-date medicines will ensure safer disposal of medicines, and better protection for households and the environment. 展开更多
关键词 Unused Medicines Expired Medicines disposal Household Risk
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Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records
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作者 Hui-Wen Pang Han-Qing Wang +4 位作者 Yi-Tian Xiao Yan Jin Yun-Hu Lu Yong-Dong Fan Zhen Nie 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1241-1256,共16页
Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production exp... Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network model.Then, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model. 展开更多
关键词 Lost circulation Risk prediction Machine learning Seismic attributes mud loss records
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泥石流暴雨个例中尺度分析 被引量:16
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作者 徐双柱 金琪 +1 位作者 肖艳娇 李俊 《气象科技》 2005年第3期240-244,共5页
对2003年7月8~9日发生在湖北中部并且造成泥石流灾害的大暴雨过程进行了中尺度分析,结果表明:①在有利的大尺度系统下产生的中小尺度系统是暴雨产生的最直接的系统;②湖北省泥石流灾害发生在特殊的地理位置,秭归、宜昌、宜都等鄂西山... 对2003年7月8~9日发生在湖北中部并且造成泥石流灾害的大暴雨过程进行了中尺度分析,结果表明:①在有利的大尺度系统下产生的中小尺度系统是暴雨产生的最直接的系统;②湖北省泥石流灾害发生在特殊的地理位置,秭归、宜昌、宜都等鄂西山地到江汉平原的过渡带是泥石流灾害的多发地;③暴雨尤其是泥石流发生地周围的历时短、局地性强的大暴雨是泥石流灾害直接的诱发原因;④中尺度系统的源地与地形有关,在西南气流的背风坡容易形成中尺度系统;⑤多普勒雷达是监测中尺度系统的强有力工具,一个中α尺度云团中可以是一个也可以有两个以上的混合回波团或带;⑥中尺度涡旋形成于低空急流左侧强正涡度中心附近。 展开更多
关键词 20037 西
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Response and assembly of abundant and rare taxa in Zaopei under different combination patterns of Daqu and pit mud:from microbial ecology to Baijiu brewing microecosystem
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作者 Yu Mu Jun Huang +5 位作者 Rongqing Zhou Suyi Zhang Hui Qin Hanlan Tang Qianglin Pan Huifang Tang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1439-1452,共14页
The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Z... The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Zaopei,especially the metabolic function of rare taxa.Here,an experiment on industrial size was designed to assess the effects of 6 combinations(3 kinds of Daqu×2 kinds of PM)on the composition and assembly of different taxa,as well as the flavor profile.The results showed that Zaopei's microbiota was composed of a few abundant taxa and enormous rare taxa,and rare bacterial and abundant fungal subcommunities were significantly affected by combination patterns.The assembly processes of abundant/rare taxa and bacterial/fungal communities were distinct,and environmental changes mediated the balance between stochastic and deterministic processes in rare bacteria assembly.Furthermore,specific combination patterns improved the flavor quality of Zaopei by enhancing the interspecies interaction,which was closely related to rare taxa,especially rare bacteria.These findings highlighted that rare bacteria might be the keystone in involving community interaction and maintaining metabolic function,which provided a scientific foundation for better understanding and regulating the brewing microbiota from the viewpoint of microbial ecology. 展开更多
关键词 Bioaugmented Daqu Artificial pit mud Abundant and rare taxa Community assembly Metabolic function
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International law obligations for the disposal of Fukushima nuclear-contaminated water under the principles of nuclear safety
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作者 Wei Gong 《Chinese Journal of Population,Resources and Environment》 2024年第1期10-19,共10页
The disposal of contaminated water from Japan’s Fukushima nuclear power plant is a significant international nuclear safety issue with considerable cross-border implications.This matter requires compliance not only w... The disposal of contaminated water from Japan’s Fukushima nuclear power plant is a significant international nuclear safety issue with considerable cross-border implications.This matter requires compliance not only with the law of the sea but also with the principles of nuclear safety under international law.These principles serve as the overarching tenet of international and China’s domestic nuclear laws,applicable to nuclear facilities and activities.The principle of safety in nuclear activities is fully recognized in international and domestic laws,carrying broad legal binding force.Japan’s discharge of nuclear-contaminated water into the sea violates its obligations under the principle of safety in nuclear activities,including commitments to optimum protection,as low as reasonably practicable,and prevention.The Japanese government and the International Atomic Energy Agency(IAEA)have breached the obligation of optimum protection by restricting the scope of assessments,substituting core concepts,and shielding dissenting views.In the absence of clear radiation standards,they have acted unilaterally without fulfilling the obligation as low as reasonably practicable principle.The discharge of Fukushima nuclear-contaminated water poses an imminent and unpredictable risk to all countries worldwide,including Japanese residents.Japan and the IAEA should fulfill their obligations under international law regarding disposal,adhering to the principles of nuclear safety,including optimum protection,the obligation as low as reasonably practicable,and prevention through multilateral cooperation.Specifically,the obligation to provide optimum protection should be implemented by re-evaluating the most reliable disposal technologies and methods currently available and comprehensively assessing various options.The standard of the obligation as low as reasonably practicable requires that the minimization of negative impacts on human health,livelihoods,and the environment should not be subordinated to considerations of cutting costs and expenses.Multilateral cooperation should be promoted through the establishment of sound multilateral long-term monitoring mechanisms for the discharge of nuclear-contaminated water,notification and consultation obligations,and periodic assessments.These obligations under international law were fulfilled after the accidents at the Three Mile Island and Chernobyl nuclear power plants.The implications of the principles of nuclear safety align with the concept of building a community of shared future for nuclear safety advocated by China.In cases of violations of international law regarding the disposal of nuclear-contaminated water that jeopardize the concept of a community of a shared future for nuclear safety,China can also rely on its own strength to promote the implementation of due obligations through self-help. 展开更多
关键词 Principles of nuclear safety disposal of nuclear-contaminated water Optimum protection Prevention As low as reasonably achievable
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Effects of key species mud snail Bullacta exarata (Gastropoda) on oxygen and nutrient fluxes at the sediment-water interface in the Huanghe River Delta, China 被引量:1
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作者 Baoquan Li Tjeerd J. Bouma +6 位作者 Quanchao Wang Laura M. Soissons Francesco Cozzoli Guanghai Feng Xiaojing Li Zhengquan Zhou Linlin Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第8期48-55,共8页
Since the mud snail Bullacta exarata was introduced for economic aquaculture in the Huanghe River(Yellow River) Delta in 2001, its quick population growth and expanded distribution make it a key-species in the interti... Since the mud snail Bullacta exarata was introduced for economic aquaculture in the Huanghe River(Yellow River) Delta in 2001, its quick population growth and expanded distribution make it a key-species in the intertidal zone of this area. This significantly contributed to the economic income of the local people, but its potential ecological impact on the benthic ecosystem remains unknown. A mesocosm study was conducted to test whether its bioturbation activities affect the microphytobenthos(MPBs;i.e., sedimentary microbes and unicellular algae)productivity and the nutrient exchange between the sediment-water interface. Our results show that the mud snail significantly impacted the dissolved oxygen(DO) flux across the sediment-water interface on the condition of normal sediment and light treatment, and significantly increased the ammonium efflux during recovery period in the defaunated sediment and dark treatment. The presence of micro-and meiofauna significantly increased the NH4-N flux in dark treatment. Whereas, in light treatment, these small animals had less effects on the DO and NH4-N flux between sediment-water interface. Our results provide better insight into the effect of the mud snail B.exarata on the ecosystem functioning via benthic fluxes. 展开更多
关键词 BIOTURBATION mud SNAIL Bullacta exarata OXYGEN FLUX nutrient FLUX benthic metabolism Huanghe River(Yellow River) Delta
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高炉水淬矿渣固井液配方与性能研究 被引量:1
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作者 顾军 尹会存 +2 位作者 高德利 王学良 周芝琴 《油田化学》 CAS CSCD 北大核心 2004年第4期304-306,共3页
用乌鲁木齐钢厂的高炉水淬矿渣(BFS),MTC激活剂BAS 1和分散剂MT 1,吐哈油田5口井使用的聚合物钻井液配制了一系列高(1 81~1 84g/cm3)、低(1 56~1 66g/cm3)密度高炉水淬矿渣固井液(BFSCF)并在不同温度下(65℃,85℃,93℃)对其性能进行... 用乌鲁木齐钢厂的高炉水淬矿渣(BFS),MTC激活剂BAS 1和分散剂MT 1,吐哈油田5口井使用的聚合物钻井液配制了一系列高(1 81~1 84g/cm3)、低(1 56~1 66g/cm3)密度高炉水淬矿渣固井液(BFSCF)并在不同温度下(65℃,85℃,93℃)对其性能进行了评定。列表给出了BFS的组成,钻井液的性能,各BFSCF的配方与性能(包括稠化时间,24小时强度,流动度及API滤失量)。实验结果表明,温度较高时BAS 1的加量应减小;在高密度BFSCF中BAS 1加量为3%~4%,低密度BFSCF中BAS 1加量大于4%;增大MT 1加量使高温(93℃)下BFSCF稠化时间延长;加入少量水泥可改善低温(65℃)下BFSCF的早期强度;高温(93℃)BFSCF的强度可达到30MPa以上。加入水泥的一种BFSCF的强度随65℃下养护龄期的延长而提高。BFSCF具有良好的沉降稳定性。表6参2。 展开更多
关键词 MT-1 MTC BFS API
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Wellbore stability analysis to determine the safe mud weight window for sandstone layers 被引量:2
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作者 DARVISHPOUR Ayoub CHERAGHI SEIFABAD Masoud +1 位作者 WOOD David Anthony GHORBANI Hamzeh 《Petroleum Exploration and Development》 2019年第5期1031-1038,共8页
The wellbore stability of a vertical well through the sandstone reservoir layers of the Asmari oil-bearing formation in south-west Iran is investigated.The safe drilling-fluid density range for maintaining wellbore st... The wellbore stability of a vertical well through the sandstone reservoir layers of the Asmari oil-bearing formation in south-west Iran is investigated.The safe drilling-fluid density range for maintaining wellbore stability is determined and simulated using FLAC3 D software and a finite volume model established with drilled strata geomechanical features.The initiation of plastic condition is used to determine the safe mud weight window(SMWW)in specific sandstone layers.The effects of rock strength parameters,major stresses around the wellbore and pore pressure on the SMWW are investigated for this wellbore.Sensitivity analysis reveals that a reduction in cohesion and internal friction angle values leads to a significant narrowing of the SMWW.On the other hand,the reduction of pore pressure and the ratio between maximum and minimum horizontal stresses causes the SMWW to widen significantly.The ability to readily quantify changes in SMWW indicates that the developed model is suitable as a well planning and monitoring tool. 展开更多
关键词 wellbore stability wellbore geomechanical property SAFE mud WEIGHT WINDOW wellbore instability risk factors DRILLING stress simulation
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Development of key additives for organoclay-free oil-based drilling mud and system performance evaluation 被引量:1
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作者 SUN Jinsheng HUANG Xianbin +3 位作者 JIANG Guancheng LYU Kaihe LIU Jingping DAI Zhiwen 《Petroleum Exploration and Development》 2018年第4期764-769,共6页
Traditional oil-based drilling muds(OBMs) have a relatively high solid content, which is detrimental to penetration rate increase and reservoir protection. Aimed at solving this problem, an organoclay-free OBM system ... Traditional oil-based drilling muds(OBMs) have a relatively high solid content, which is detrimental to penetration rate increase and reservoir protection. Aimed at solving this problem, an organoclay-free OBM system was studied, the synthesis methods and functioning mechanism of key additives were introduced, and performance evaluation of the system was performed. The rheology modifier was prepared by reacting a dimer fatty acid with diethanolamine, the primary emulsifier was made by oxidation and addition reaction of fatty acids, the secondary emulsifier was made by amidation of a fatty acid, and finally the fluid loss additive of water-soluble acrylic resin was synthesized by introducing acrylic acid into styrene/butyl acrylate polymerization. The rheology modifier could enhance the attraction between droplets, particles in the emulsion via intermolecular hydrogen bonding and improve the shear stress by forming a three-dimensional network structure in the emulsion. Lab experimental results show that the organoclay-free OBM could tolerate temperatures up to 220 ?C and HTHP filtration is less than 5 m L. Compared with the traditional OBMs, the organoclay-free OBM has low plastic viscosity, high shear stress, high ratio of dynamic shear force to plastic viscosity and high permeability recovery, which are beneficial to penetration rate increase, hole cleaning and reservoir protection. 展开更多
关键词 organoclay-free OIL-BASED drilling mud rheology MODIFIER EMULSIFIER fluid loss REDUCER weak gel reservoir protection
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Study on Safety and Stability Evaluation of Waste Disposal Field of a Hydropower Station Based on <i>In Situ</i>Monitoring
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作者 Kun Sun Houcai Sun +1 位作者 Yang Lu Qianzhu Zhang 《Journal of Geoscience and Environment Protection》 2020年第5期221-230,共10页
Reasonable site selection, blocking to meet design standards, interception and drainage and other protective measures are the basic conditions for not causing disaster in slag disposal site. A hydropower station is lo... Reasonable site selection, blocking to meet design standards, interception and drainage and other protective measures are the basic conditions for not causing disaster in slag disposal site. A hydropower station is located in mountainous area, the amount of slag abandoned is large, the grade of slag disposal field is high, and the site selection is difficult. On the basis of in Situ deformation monitoring, the slope stability of slag disposal site is calculated by Swedish arc method through the analysis of the scale, grade, site selection, surrounding environment, cut and discharge, blocking and protection design standards of slag disposal site. Under normal and abnormal operating conditions, the slope stability of slag disposal site meets the requirements of the code, and the results of in Situ deformation monitoring verify the calculation results of slope stability of slag disposal site by Swedish circular arc method. 展开更多
关键词 Soil and Water Conservation HYDROPOWER Station Waste disposal FIELD In Situ MONITORING Safety and Stability
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Rock Mass Characteristics in Beishan,A Preselected Area for China's High-Level Radioactive Waste Disposal 被引量:2
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作者 WEI Xiang GUO Ying +4 位作者 CHENG Hanlie MENG Xiangdong CHENG Mingqian YANG Ting XU Chunmei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第2期362-372,共11页
Geological and hydrological characteristics, joint geometric features, rock physical and mechanical properties and rock mass quality are studied in the Beishan area, preselected for China5 s high-level radioactive was... Geological and hydrological characteristics, joint geometric features, rock physical and mechanical properties and rock mass quality are studied in the Beishan area, preselected for China5 s high-level radioactive waste(HLW) disposal engineering. A comprehensive survey method is developed to study joint geometric features in the outcrop and samples from borehole BS06 into the Xinchang rock mass were tested. The optimal joint sets are determined by rose diagrams and equal-area lower hemisphere plots of joint poles. Results show that: 1) the distribution of joint occurrence obeys a normal distribution, while the distribution of joint spacing obeys a negative exponential distribution; 2) concentric circular and tangent circular sampling windows are applied to study the trace length and the trace midpoint density. Results indicate that tangent circular sampling window is more stable and reasonable; 3) Beishan granite shows high density, low porosity and high strength based on many laboratory tests and the physical properties and mechanical properties are closely related; and4) a synthesis index, Joint Structure Rating(JSR), is applied to evaluate the quality of rock mass. Through the research results of rock mass characteristics, the Xinchang rock mass in the Beishan preselected area has the favorable conditions for China's HLW disposal repository site. 展开更多
关键词 GEOLOGY HYDROLOGY RADIOACTIVE waste disposal(HLW) rock mass quality joint GEOMETRIC features physical/mechanical properties
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核磁共振录井技术快速测定岩样物性的方法 被引量:18
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作者 王志战 周立发 +1 位作者 王守军 慈兴华 《录井工程》 2005年第2期30-32,共3页
该文从核磁共振录井的测量机理入手,阐述了岩样T2谱的形态主要受岩性、孔喉大小及孔隙流体性质的影响及关系。以国外核磁共振(NMR)仪器为例,介绍了有效孔隙度的求取、渗透率评价模型、可动、束缚流体饱和度、有效含油饱和度等的计算公... 该文从核磁共振录井的测量机理入手,阐述了岩样T2谱的形态主要受岩性、孔喉大小及孔隙流体性质的影响及关系。以国外核磁共振(NMR)仪器为例,介绍了有效孔隙度的求取、渗透率评价模型、可动、束缚流体饱和度、有效含油饱和度等的计算公式。介绍了岩样原始含油饱和度的测量方法,对样品的处理、检测流程作了分析。文章认为该技术不仅适用于碎屑岩,在碳酸盐岩地层也有效,测量的孔隙度与常规分析相对误差≤10%,是应该大力推广的新技术。 展开更多
关键词 T2
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Structural mechanism and construction method of mud and water inrush in Xiangyun tunnel of Guangtong-Dali railway
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作者 WANG Yawei 《Global Geology》 2019年第3期167-178,共12页
Mud and water inrush in tunnel is a common problem in the construction process. Nowadays, the research and classification on this are mostly focused on karst situations. According to the characteristics of the surroun... Mud and water inrush in tunnel is a common problem in the construction process. Nowadays, the research and classification on this are mostly focused on karst situations. According to the characteristics of the surrounding rock and damage forms of the tunnel in the studied area, the author analyzed the geological and structural characteristics of mud and water inrush in tunnel and obtained their construction type. Meanwhile, the advanced water detection under the complex geological conditions was studied by using induced polarization method, transient electromagnetic method and three-dimensional seismic method, it can be concluded that the water-rich fracture zone exists within the detection range with a risk of large mud and water inrush disaster. The concrete construction treatment measures are put forward:①cement-water glass binary slurry is selected as the material for ground and hole grouting, its advantage is that the gel time can be controlled, and it has certain grout ability in the strata with large permeability coeffcient, which is conducive to excavate construction immediately after grouting.②applying the mature retrograde grouting construction can reduce grouting time and improve the excavation efficiency. 展开更多
关键词 mud and water inrush geological model Xiangyun TUNNEL Guangtong-Dali RAILWAY STRUCTURAL mechanism construction method
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