“处境”的“处”读chù吗?

电视剧《向阳理发店》中刘志美这个人物有句台词:“难道你们就真的理解不了我的处境?”刘志美的扮演者把这句话中的“处境”的“处”读成了“”。笔者认为不妥。另外,像电视剧《大哥》中演员把“处理”读成“理”,把“相处”读成“相”一样,在影视作品和日常生活中,读错“处”音的例子真不少。因此。

Pretreatment of coking wastewater using anaerobic sequencing batch reactor (ASBR)

A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical methane potential (BMP)of the coking wastewater in the acclimated granular biomass was measured. At the same time, some fundamental technological factors, such as the filling time and the reacting time ratio (tf/tr), the mixing intensity and the intermittent mixing mode, that affect anaerobic pretreatment of coking wastewater with ASBR, were evaluated through orthogonal tests. The COD removal efficiency reached 38％～50％ in the stable operation period with the organic loading rate of 0.37～0.54 kg COD/(m3.d) at the optimum conditions of tf/tr, the mixing intensity and the intermittent mixing mode. In addition, the biodegradability of coking wastewater distinctly increased after the pretreatment using ASBR. At the end of the experiment, the microorganism forms on the granulated sludge in the ASBR were observed using SEM (scanning electron microscope) and fluoroscope. The results showed that the dominant microorganism on the granular sludge was Methanosaeta instead of Methanosarcina dominated on the inoculated sludge.

Factors affecting ice crystal purity during freeze concentration process for urine treatment

Freeze concentration has great potential in treating wastewaters containing soluble pollutions. It is important for freeze concentration process to produce ice crystals with large size and high purity. In this work raw urines of 4660 -7914 mg/L in COD, 512. 71 -872. 41 mg/L in NH3 -N and 22600 -28800 μs/cm in electric conductivity were studied. Urines were frozen by a digital refrigerated circulator bath. Ice crystals were purified by ice-water steep and vacuum filtration. The COD, NH3 - N, and electric conductivity levels of the melted ices were measured to reflect ice crystal purity. Effects of coolant temperature, ice crystal shape, initial solution temperature, solution concentration, ice seeding, re-crystallization process and crystallization time on ice crystal purity were analyzed. The results show that an appropriate coolant temperature, suspended ice crystals, an initial solution temperature of about 6 ℃, introduction of seed ice, addition of re-crystallization process, and crystallization time of less than 30 min axe in favor of producing ice crystals with high purity. Under such conditions, more than 99 percent of inorganic salts, COD and NH3 - N sources in raw urine could he removed.

A New Method for Effluent Treatment System Design

this paper mainly discusses the design of distributed effluenttreatment systems with single contami- nant. A new method is putforward and four basic rules are provided. The key point of themethod is that global optimality is obtained by guaranteeing theoptimality of each step taken in the design. Costs per unit mass ofremoved contaminant are used as a scale to choose the nextcombination of an effluent stream and a treatment process. Theremaining problem is updated after each choice. As for multiplecontaminants, a two-stage method is adopted.

Stress corrosion cracking behaviour of 7xxx aluminum alloys: A literature review

Stress corrosion cracking （SCC） is degradation of mechanical properties under the combined action of stress and corrosive environment of the susceptible material. Out of eight series of aluminium alloys, 2xxx, 5xxx and 7xxx aluminium alloys are susceptible to SCC. Among them, 7xxx series aluminium alloys have specific application in aerospace, military and structural industries due to superior mechanical properties. In these high strength 7xxx aluminium alloys, SCC plays a vital factor of consideration, as these failures are catastrophic during the service. The understanding of SCC behaviour possesses critical challenge for this alloy. The main aim of this review paper is to understand the effect of constituent alloying elements on the response of microstructural variation in various heat-treated conditions on SCC behavior. Further, review was made for improving the SCC resistance using thermomechanical treatments and by surface modifications of 7xxx alloys. Apart from a brief review on SCC of 7xxx alloys, this paper presents the effect of stress and pre-strain, effect of constituent alloying elements in the alloy, and the effect of environments on SCC behaviour. In addition, the SCC behaviours of weldments, 7xxx metal matrix composites and also laser surface modifications were also reviewed.

Kinetics of aerobically activated sludge on terylene artificial silk printing and dyeing wastewater treatment

Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kinetics pa-rameters determined from experiment were applied to evaluate the biological treatability of wastewater. Experiments showed that COD removal could be divided into two stages, in which the ratio BOD/COD (B/C) was the key factor for stage division. At the rapid-removal stage with B/C>0.1, COD removal could be described by a zero order reaction. At the mod-erate-removal stage with B/C<0.1, COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (KS) were 0.0208-0.0642 L/(gMLSS)h and 0.44-0.59 (gCOD)/L respectively at 20 C-35 C. Activation energy (Ea) was 6.05104 J/mol. By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater. But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater, such as papermaking, beer, phenol wastewater, etc. The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up and efficient operation of TPD wastewater treatment.

Variable refractive index in environment matte

Environment matting and compositing is a technique to extract a foreground object, including color, opacity, reflec- tive and refractive properties, from a real-world scene, and synthesize new images by placing it into new environments. The description of the captured object is named environment matte. Recent matting and compositing techniques can produce quite realistic images for objects with complex optical properties. This paper presents an approximate method to transform the matte by simulating variation of the foreground object’s refractive index. Our algorithms can deal with achromatous-and-transparent ob- jects and the experimental results are visually acceptable. Our idea and method can be applied to produce some special video effects, which could be very useful in film making, compared with the extreme difficulty of physically changing an object’s refractive index.

Security evaluation of compounded microbial flocculant

A new kind of compounded microbial flocculant (CMBF) for water and wastewater treatment has been developed through biological technology. In order to discuss its biological security, four groups of experiments, rat acute toxicity test via mouth, salmonella assay in vitro, mouse micronucleus in vivo test and teratogenesis test were conducted to evaluate its general toxicity, genotoxicity and generative toxicity. The experimental results showed that this type of compounded microbial flocculant was a substantial non-toxic substance based on the fact that LD50 value was over 10 mg/kg. The results from salmonella in vivo test and mouse micronucleus in vivo test revealed that the compounded microbial flocculant is a genetically non-toxic substance. Furthermore, compounded microbial flocculant has little effect on the growth of all the rats, and any morphologic abnormal phenomenon hasn’t appeared.

Application of CASS in Treating Domestic Sewage at Low Temperatures

The feasibility of using CASS technique for treating domestic sewage at low temperatures was investigated. The results indicate that for domestic sewage (averagely, ρ(BOD5)=295.7 mg/L; ρ(CODCr )= 811.7 mg/L; ρ(SS)= 119.6 mg/L), the removal rates are 95.3%, 85.7%, 91%, respectively. The CASS technique is operable in a wide range of temperature (about -5～20 ℃), but φ(S) and ρ(S) values are higher at low temperature than those at normal temperature. A low temperature is good for oxygen transmission and the cyclic fluctuation of DO (dissolved oxygen) is benefit for the removal of P and N, preventing the sludge from bulking.

Interactions of Aquaculture and Waste Disposal in the Coastal Zone

Throughout the world, the coastal zones of many countries are used increasingly for aquaculture in addition to other activities such as waste disposal. These activities can cause environmental problems and health problems where they overlap. The interaction between aquaculture and waste disposal, and their relationship with eutrophication are the subjects of this paper. Sewage discharge without adequate dispersion can lead to nutrient elevation and hence eutrophication which has clearly negative effects on aquaculture with the potential for toxic blooms. Blooms may be either toxic or anoxia-causing through the decay process or simply clog the gills of filter-feeding animals in some cases. With the development of aquaculture, especially intensive aquaculture, many environmental problems appeared, and have resulted in eutrophication in some areas. Eutrophication may destroy the health of whole ecosystem which is important for sustainable aquaculture. Sewage discharge may also cause serious public health problems. Filter-feeding shellfish growing in sewage-polluted waters accumulate micro-organisms, including human pathogenic bacteria and viruses, and heavy metal ion, presenting a significant health risk. Some farmed animals may also accumulate heavy metals from sewage. Bivalves growing in areas affected by toxic algae blooms may accumulate toxins (such as PSP, DSP) which can be harmful to human beings.

Degradation of chlorophenol by in－situ electrochemically generated oxidant

A novel in-situ electrochemical oxidation method was applied to the degradation of wastewater containing chlorophenol. Under oxygen sparging, the strong oxidant, hydrogen dioxide, could be in-situ generated through the reduction of oxygen on the surface of the cathode. The removal rate ofchlorophenol could be increased 149% when oxygen was induced in the electrochemical cell. The promotion factor was estimated to be about 82.63% according to the pseudo-first-order reaction rate constant (min^-1). Important operating parameters such as current density, sparged oxygen rate were investigated. Higher sparged oxygen rate could improve the degradation of chlorophenol. To make full use of oxygen, however, sparged oxygen rate of 0.05 m3/h was adopted in this work. Oxidation-reduction potential could remarkably affect the generation of hydrogen peroxide. It was found that the removal rate of chlorophenol was not in direct proportion to the applied current density. The optimum current density was 3.5 mA/cm^2 when initial chlorophenol concentration was 100 mg/L and sparged oxygen rate was 0.05 m^3/h.

An Enhanced Hadoop Heartbeat Mechanism for MapReduce Task Scheduler Using Dynamic Calibration

MapReduce is a popular program- ming model for processing large-scale datasets in a distributed environment and is a funda- mental component of current cloud comput- ing and big data applications. In this paper, a heartbeat mechanism for MapReduce Task Scheduler using Dynamic Calibration （HMTS- DC） is proposed to address the unbalanced node computation capacity problem in a het- erogeneous MapReduce environment. HMTS- DC uses two mechanisms to dynamically adapt and balance tasks assigned to each com- pute node： 1） using heartbeat to dynamically estimate the capacity of the compute nodes, and 2） using data locality of replicated data blocks to reduce data transfer between nodes. With the first mechanism, based on the heart- beats received during the early state of the job, the task scheduler can dynamically estimate the computational capacity of each node. Us- ing the second mechanism, unprocessed Tasks local to each compute node are reassigned and reserved to allow nodes with greater capacities to reserve more local tasks than their weaker counterparts. Experimental results show that HMTS-DC performs better than Hadoop and Dynamic Data Placement Strategy （DDP） in a dynamic environment. Furthermore, an en- hanced HMTS-DC （EHMTS-DC） is proposed bv incorporatin historical data. In contrastto the ＂slow start＂ property of HMTS-DC, EHMTS-DC relies on the historical computation capacity of the slave machines. The experimental results show that EHMTS-DC outperforms HMTS-DC in a dynamic environment.

Polychlorinated dibenzo-p-dioxins and dibenzofurans in flue gas emissions from municipal solid waste incinerators in China

Polychlorinated dibenzo-p-dioxins and furans （PCDD/Fs） emissions in flue gas from two types of municipal solid waste incinerators （MSWIs） most commonly used in China were investigated in this study. The selected incinerators include two grate-type MSWIs： MSWI-A （350 t/d） and MSWI-B 050 t/d）, and two fluidized bed MSWIs： MSWI-C （400 t/d） and MSWI-D （400 t/d）, which are all equipped with semi-dry lime scrubber and bag filter except MSWI-D equipped with cyclone and wet scrubber （WS） as air pollutant control device （APCD）. Results indicated that the emission concentration and the international toxic equivalents （I-TEQs） of the PCDD/Fs from the stacks were in the range of 1.210-10.273 ng/Nm^3 and 0.019-0.201 ng I-TEQ/Nm^3, respectively. They were greatly lower than the emission regulation standard of PCDD/Fs in China （1.0 ng I-TEQ/Nm^3）. However, only the PCDD/Fs emission level from MSWI-C was below 0.1 ng I-TEQ/Nm^3. Although the homologue profiles were distinct, the contributions of the 2,3,7,8-subsituted congeners to the total I-TEQ were similar among all the investigated MSWIs. Two major 2,3,7,8-substituted congeners, 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDD, account for 47% and 9% （average values） of the total I-TEQ values, respectively. The correlation between PCDD/Fs levels and composition of flue gas was also discussed.

Technological Choice and Challenge in North AmericanGinseng Production

in recent years, there have been draniatic increases in the production of NorthAmerican ginseng around the tvorld. These increases and the expectation of their continuation havegiven rise to a need to critically evaluate all aspects of North American ginseng (Panar quinquefoliumL.) production. Employing a system approach, the production of North American ginseng can be di-vided into its principal components that include seed preparation and planting, growing environmentcreation and maintenance, plant health maintenance, harvest and post-harvest activities, and productprocessing. As competitive industry forces are beginning to result in increased global competition, itis prudent to carefully assess both the strengths and weaknesses of the North American ginseng pro-duction system. It is clear that the utilization of appropriate technology will be a key to future industrysuccesses and the continuity of successful economic development that is associated with the industry.It is recognized that careful technological choices and changes will be required to successfully facethe challenges of an ever increasingly competitive global ginseng marketplace.

Investigation and analysis of hazardous waste in the Three Gorges Area of Chongqing region

This article describes the investigation of hazardous waste (HW) in the Three Gorges Area of Chongqing region, which indicates that by May 2002, the dumped HW therein amounted to 14 600 t and was mainly distributed in five districts and counties with 11 000 t in Fuling, 1 650 t in Fengdu, 950 t in Wanzhou; 630 t in Wushan and 430 t in Yunyang. The total amount was composed of 9 670 t chromic residue, 2 310 t waste oil and residue, 410 t waste (false) fertilizer, 28 t waste chemical medicine, 26 t waste materials and 2 200 t other things including acid residue, waste asbestos, fluorine silicate, pigment, additive, waste acid, alkali, nitric acid, vitriol, lead mud, storage battery, calcium carbide, potassium cyanide, polluted soil, discard dynamite, waste packing barrel of cyanides, etc. In all of the HW, 578 t can be treated by chemical neutralization and stabilization technology such as redox, chemical precipitation, acid and alkali neutralization, etc., and the rest is temporarily untreatble and should be removed and piled at a temporary storage site above the 177 m water level of the dam with an aim to be transported to a future disposal site for innocuous treatment.

DESIGN AND APPLICATION OF DYNAMIC MONITORING AND VISUALIZATION MANAGEMENT INFORMATION SYSTEM OF KARST LAND ROCKY DESERTIFICATION

In order to study the spatial-temporal change and environmental management of regional karst LUCC (land use and land cover change) and its causative environmental effect-rocky desertification by integrating qualitative analysis and quantitative analysis, and relying on RS, GIS and GPS (3S) techniques, karst land rocky derification dynamic monitoring and visualization management information system (KLRD.DMVM.IS) is framed, which includes design aim and structure model, function design, database design and model system design. The model system design gives priority to dynamic monitoring, drive force diagnosis, comprehensive evaluation and decision support of karst rocky desertification. From the viewpoint of model type, mathematic expression and its meaning, the dynamic monitoring models are concretely devised to reflect the spatial and temporal changing features and the trend of karst LUCC and rocky desertification. Taking Du'an Yao Autonomic County of Guangxi as an example, the KLRD.DMVM.IS is systematically analyzed in the application of the process and trend of karst LUCC and rocky desertification in Du'an County, and it provides the technical support for the study on karst land rocky desertification.

Performance of BAC process for treatment of micro-polluted water

Biological activated carbon (BAC) has been developed on the granular activated carbon by immobilization of selected and acclimated species of bacteria to treat the micro-polluted water. The BAC removal efficiencies for nitrobenzene, permanganate index, turbidity and ammonia were investigated. Effects of shock loading and SEM (Scanning Electron Microscope) observation on BAC were studied. Backwashing and its intensity of BAC were also discussed. The results showed that BAC took short time to start up and recover to the normal condition after shock loading. The shock loading studies showed that the removal efficiency of BAC was not completely inhibited even at high concentration of nitrobenzene. Backwashing performed once every 10-20 d, or an average of 15 d. Backwashing intensity was 12-14 L/(s·m2) with air and 3-4 L/(s·m2) with water.

Experimental Investigation of Environmental Hydraulic Parameters for Dual Mixed Media Biofilter for Greywater Treatment

Laboratory scale model of DMMBF （dual mixed media biofilter） were designed and installed in AI-Mustansiriya University Environmental Hydraulic Lab. Experiments were conducted using two mixed layers through PVR column--2.2 m height and 300 mm diameter. The first mixed media filter of depth 640mm mixed of sand, rice husk and granular activated carbon. The percentage volume mix is 1：1：1. While the other mixed media of depth 740 mm, consisting of coal, crash porcelinaite, rock and granite with equally percentage volume. Fifty samples were collected during the experiments, which was spread over a period of forty two weeks. The obtained results indicate that when the flow loading raised from 0.15 L/min to 2.7 L/rain, the removal efficiency of BOD decreased 8%-11%, and the removal efficiency of COD deceased 3%-4%, while the removal efficiency of turbidity increased with the decreasing of hydraulic loading. The results showed that the removal efficiency of turbidity is more than 95% at the lower discharge （0.15 L/min）. Therefore, infiltration should be conservatively designed using low loading rates.

Problems of drinking water treatment along Ismailia Canal Province, Egypt

The present drinking water purification system in Egypt uses surface water as a raw water supply without a preliminary filtration process.On the other hand,chlorine gas is added as a disinfectant agent in two steps,pre-and post-chlorination.Due to these reasons most of water treatment plants suffer low filtering effectiveness and produce the trihalomethane(THM) species as a chlorination by-product.The Ismailia Canal represents the most distal downstream of the main Nile River.Thus its water contains all the proceeded pollutants discharged into the Nile.In addition,the downstream reaches of the canal act as an agricultural drain during the closing period of the High Dam gates in January and February every year.Moreover,the wide industrial zone along the upstream course of the canal enriches the canal water with high concentrations of heavy metals.The obtained results indicate that the canal gains up to 24.06×106 m3 of water from the surrounding shallow aquifer during the closing period of the High Dam gates,while during the rest of the year,the canal acts as an influent stream losing about 99.6×106 m3 of its water budget.The reduction of total organic carbon(TOC) and suspended particulate matters(SPMs) should be one of the central goals of any treatment plan to avoid the disinfectants by-products.The combination of sedimentation basins,gravel pre-filtration and slow sand filtration,and underground passage with microbiological oxidation-reduction and adsorption criteria showed good removal of parasites and bacteria and complete elimination of TOC,SPM and heavy metals.Moreover,it reduces the use of disinfectants chemicals and lowers the treatment costs.However,this purification system under the arid climate prevailing in Egypt should be tested and modified prior to application.