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Ruthenium is widely used as catalyst, magnetic recording and electrode materials. In this study, high-purity (≥99.995 wt%) ruthenium sponge was synthesized from crude ruthenium (≤99.9 wt%) by chemical refining technique. Initially, crude Ru was transformed into H2RuCl6 by distilling treatment. The H2RuCl6 was, then, added with NH4Cl powder to precipitate (NH4)2RuCl6 powder. Afterward, the (NH4)2RuCl6 powder was ignited in air and transformed into RuO2. Finally, RuO2 was changed to Ru by hydrogen reduction method. Impurities included in the starting Ru powder were eliminated after distillation and precipitation treatments. As-obtained ruthenium particles were spherical-like agglomeration, the average size was about 6 μm and the powder density was 11.83 g/cm3. The details of chemical transforming mechanisms in the refining process were described.

CoCrPt-SiO2granular film is well known as a perpendicular magnetic recording (PMR) media. To control the segregated structure of the recording layer, the role of the Ru underlayer is important. CoCrPt-SiO2perpendicular recording films were prepared by magnetron sputtering, with a series of Ru films as seed layer. The microstructure of Ru seed layers and their influences on the grain size, roughness and surface morphology of CoCrPt-SiO2granular films were investigated. It was found that the microstructure of seed layer obviously effected the structure and grain isolation of recording layers. The grain size and roughness of CoCrPt-SiO2recording layer were both increased with increasing the thickness of Ru seed layer. It is concluded that the thin and rough Ru seed layer is suitable for high-density magnetic recording media, and Ru seed layer with suitable thickness is very helpful for the achievement of perfect isolation and excellent magnetic properties. The result revealed that it was relatively easy for the CoCrPt grains to get perfect isolation with Ru thickness of 70 nm.

The effects of oxidized copper ores which came from Yunnan province were carried out by using ammonialeaching methods in the laboratory.In order to seek the optimum leaching conditions under normal temperature and pressure,we conducted a series of validation experiments. Theoptimum conditions were obtained as follows: ammonia concentration 2.5mol/L, ammonium sulfateconcentration 2.5mol/L,grinding fineness about 80% -0.074mm, liquid-solid ratio 2.5:1and leaching time was 2.5h. Under these experimental conditions, the copper leaching rate could reach 69.91%.

For the comprehensive recovery of copper, zinc, silver and iron from the zinc volatile kiln slag in Xining, exploratory experiments were conducted by adopting single flotation, magnetic separation and combined process of magnetic separation and flotation. The results showed that the above process cannot effectively recover copper, zinc and silver from the ore. The recovery of iron is better by single magnetic separation. The grade of iron concentrate reaches 69.05% and the recovery is 41.86%.

Accurate estimation of battery state of charge (SOC) is important to ensure operation of electric vehicle. Since a nonlinear feature exists in battery system and extended kalman filter algorithm performs well in solving nonlinear problems, the paper proposes an EKF-based method for estimating SOC. In order to obtain the accurate estimation of SOC, this paper is based on composite battery model that is a combination of three battery models. The parameters are identified using the least square method. Then a state equation and an output equation are identified. All experimental data are collected from operating EV in Beijing. The results of the experiment show that the relative error of estimation of state of charge is reasonable, which proves this method has good estimation performance.

In order to solve the problem of data collision in the electronic countermeasures simulation scenario edition, a scenario data collision detecting algorithm based on productive inferring, whats more, a scenario data collision detection system for electronic countermeasures simulation is designed and actualized. This system can be integrated into electronic countermeasures simulation system regarded as a component, to check the scenario data and ensure the datas rationality.

Ce3+activated terbium aluminum garnet ((Tb1-xCex)3Al5O12, 0≤x≤0.05) phosphors have been converted from their precursors synthesized via co-precipitation from mixed solutions of aluminum and rare earth nitrates with ammonium hydrogen carbonate (AHC) as the precipitant. Detailed characterizations of the precursors and the phosphor oxides were performed by the combined techniques of X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FE-SEM), differential scanning calorimetry/thermogravimetry (DSC/TG), and photoluminescence spectroscopy. The co-precipitated precursors possess a general composition of (NH4)x(Tb,Ce)3Al5(CO3)y(OH)z·nH2O, and the particles, having diameters of about 50nm, are well dispersed. Calcining the precursors at 1000°C for 4 h in the air and then reducing in a hydrogen atmosphere at 1000°C for 2 h yielded a phase pure garnet solid-solution of (Tb1-xCex)3Al5O12. The cubic lattice of garnet allows the Ce3+activators to reside at the dodecahedral interstitial sites. The resultant garnet phosphors with various Ce3+contents exhibit nearly identical positions of the PLE/PE bands, but significantly different intensities. Upon blue-light excitation at 470nm, the garnet phosphors exhibit broad band emissions peaking at 560nm. The garnet phosphors show a luminescence quenching concentration of 1.5at% for Ce3+.

Based on the requirement of small errors in measuring roundness (cylindricity) error, a leveling methodology which using a dual-point vertical layout has been put forward and analyzed. According to the direction cosine of the axis of workpiece, the amount of leveling has been defined and calculated, which overcomes the problem brought by manual adjustment technology and forms theoretical bases of fast, accurate leveling and high precise measurement. The assessment of roundness (cylindricity) error is to search for a center (cylinder axis) which satisfies the minimum condition. Due to the reliance of initial solutions and relative slowness in terms of convergence precision and convergence rate when using Nelder-Mead simplex method, a combinative method of Quasi-Newton and N-M simplex method has been proposed which achieves a fast, accurate search for global optimums. With the proof of the simulation of classical testing functions using Matlab and the measured data, the convergence rate and precision will be enhanced effectively has been certified with the combination of both methods mentioned above which ensuring and improving the measuring precision of workpiece.

The hardware structure of a liquid level detection system for lead-acid battery was briefly introduced. The system adopts AT89C51 MCU as host module, combined with display storage, extended storage and the watch dog technology. The slave module adopts AT89C2051 MCU, which driver the linear CCD to realize non-contact measurement in acidic and corrosive conditions. The infrared transmission module uses RS-232 serial-to-infrared technology to realize wireless data delivery. The damage due to sensor corrosion could be avoided in this system. Compared with other similar equipments, this system has the advantages of simple structure, small volume, low cost, high measure precision and convenient maintenance.

A robust adaptive fuzzy control scheme combined with an adaptive fuzzy control algorithm and H∞ control model is proposed for the trajectory tracking control of robot manipulator with structured and unstructured uncertainties. The adaptive fuzzy control algorithm is employed to approximate structured uncertainties, and the nonlinear robust H control model is designed to eliminate the effect of the unstructured uncertainties and approximation errors. The validity of the robust adaptive fuzzy control scheme is demonstrated by numerical simulations of a two-link rotary robot manipulator.

Agile manufacture execution system is the centre of whole system. The structure and function of the execution system are analyzed, the characteristics of Agent is also given. The Agent modeling method is used in the system, the function or unit can be transformed into Agent, so the setup structure for execution system of the agile manufacture system is build, and the resources, requirements are all brought into the networks. The systems operation relies on the interaction among the functional Agents.

The design of a LED illumination control system based on ARM, infrared technology and ZigBee is described. With the core of S3C44B0X and the infrared sensor collecting the temperature information, the system uses ZigBee technology to do real time monitoring. Through the experiment, the system can make the safe, real time and effective control. It is meaning for the development of the future LED illumination.)

The principle of restraining the harmonic using the series reactors was introduced and the relationships between circuit condition and the harmonic current were analyzed in this paper.The considered problems in selecting the reactance rate were discussed. On the base of power quality test results at a certain region in China, a selection method of reactance rate of series reactors, rated voltage and capacity of a capacitor were put forward to realize the compensation for reactive power.

The leading phase operation of generator is an effective method to reduce voltage of the key point which is much high in valley load period. This paper reviews the history on leading phase of generator and introduces the current situation on stable monitoring of the generators leading phase capacity. Meanwhile, this paper proposes main restricted conditions of generator leading phase and analyzed in details. At last some experiments are performed for part generating sets with a capacity of 100MW above in one province and obtained the experiment results on voltage regulation through leading phase of synchronous generating sets.

According to Wiener-Khintchine theorem, autocorrelation function of an image was proved that can be used as sharpness evaluation function. An image sharpness index k is proposed and the relationship between content of high frequency components of an image and the width d of its autocorrelation function main lobe was constructed through Fourier transformation. The direct ration relationship between the sharpness index k of an image and the width d of its autocorrelation function main lobe was also validated by experiments. Theoretical analysis and experiment results indicate that d increases when an image is blurry and d decreases when the image is clear.

A kind of portable digital storage oscilloscope (DSO) is developed in this paper. It builds trigger, storage, measurement module for embedded system with programmable logic resource of FPGA chip. The external digital circuits of a digital oscilloscope is achieved. And it saves a lot of cost by implanting NIOS II soft-core processor as the control unit of the system in the FPGA. This system has the function of automatic frequency control (AFC) and automatic gain control (AGC), and it can measure the signal conveniently.

Ignition energy of aviation ignition equipment is an important parameter for reliable launch of air jet. The factors are quite more that influence ignition energy and increasing the charge voltage of capacitance with high efficiency is an approach which increasing ignition energy efficiently. The charge voltage is the output voltage of switching power of ignition device. A mathematic model was constructed for switching power, and a mathematic expression were deduced about output voltage uo with input voltage ui and other elements parameters of switching power supply. An important conclusion were obtained which uo mainly depended on input voltage ui, load RL, dynatron collector peak current ICM on certain condition through a smart transform. When increasing ui, RL, ICM , uo increasing observably. The PSpice circuit simulation software is used for simulation, and the results show that the above conclusion is valid and feasible.

In this paper, for the purpose of ultrasonic signal compression and the coherent noise depressing in nondestructive test of aluminum alloy forging, the mathematical model of defect echoes is discussed and confirmed. And then the wavelet kernel is also confirmed according the waveform of the defect echoes. As the algorithms of standard hard thresholding and soft thresholding of wavelet transform can not bring out effective compression and depression to the coherent noise, an adaptive wavelet thresholding algorithm is introduced. Experimental results indicate that the adaptive wavelet thresholding algorithm can offer effective signal compression and depression to the coherent noise.

Windows network packets capture technology is closely related with Windows network protocol architecture. Paper first introduces the Windows network protocol implementation, then analyze the network packets capture technology in the user mode and kernel mode, moreover discuss the data capture technology at the application layer, including API interception technology, dynamic library replacement technology and database trigger technology, finally, the various network data acquisition technology are analyzed, and what kind of data acquisition technology is used depends on the purpose of data capture and the characteristics of the target information system.

Geo-accumulation Index and Enrichment Factor were applied in source apportionment of Changchun atmospheric particulate matter. By mutual comparison with the results respectively, explored the similarities and differences. The result shows that the Geo-accumulation index and Enrichment Factors likes Zn, Cd are more serious, meanwhile the urban dust, soil wind dust, coal dust are the mainly pollution sources of Changchun air pollution, both methods can make a scientific evaluation to the human impact of Changchun particulate pollution in the atmosphere, provide an important reference for atmospheric particulate matter source apportionment.

We analyze the road environment of the present urban main road and the motor vehicle traffic conditions firstly, from which we see that crosswalks should be added and some intersections should be signal control optimized. Then using the timing linear control system theory which is suitable for China, the paper optimizes the crosswalk and intersection signal timing. Simulation is conducted with simulation software of VISSIM in the end, obtaining that after arterial road coordination, although a crosswalk is added in optimized arterial road, the total stop delay and the travel time of the mainstream vehicles are effectively reduced. The program satisfies the need for pedestrian crossing, and obtains better green wave band of arterial road.

The anticorrosive work for pipeline is a basic work. It is significant for us to lengthen pipeline working life and enhance the operation reliability. In this article, the corrosive status and reasons for pipeline in China were narrated. The new anticorrosive coating that epoxy heavy anticorrosive over-rust primer/interpenetrating polymer network (IPN) topcoat was opened up. In the lab, the anticorrosive coating by analyzed with scanning electron microscopy (SEM), and X-ray photoelectron spectrum (XPS). The corrosion behavior of the new anticorrosive coating was studied. The conclusion is that the epoxy heavy anticorrosive over-rust primer/IPN topcoat is superior in anticorrosive properties.

In order to get the optimistic structure property and design parameters of a car body, the system of vehicle body concept design (VCD-ICAE) was developed by us to make the body design in the conceptual phase in the paper. It can build parametric geometry modeling and FEM model of body-in-white (BIW) automatically, and the structural stiffness was calculated. Based on the former model, a multi-objective optimization of the total body was designed to afford the reasonable parameters for detailed model of BIW, which realized lightweight of the whole body and high stiffness. In the paper, the total theory and flowchart of vehicle body concept design were afforded. An example with real body’s data was shown to prove the validity of the multi-objective optimization module in VCD-ICAE system. Finally, the optimal design scheme of the body was provided.

This paper introduces the design of telemedicine ECG monitoring system based on GPRS.This system combined holter monitoring technology and advanced wireless public communication network, which realizes user outside the hospital can be achieved by heart disease remote real-time monitoring function.This paper firstly introduced the structure design of this system, and then the electrocardio monitoring terminal, the communication circuit as well as the software and hardware of monitoring centers respectively. Clinical experiments showed that this system can realize remote real-time monitoring, and has important clinical significance.

With the rapid development and integration of the Internet, wireless communication network and the Internet of Things, the Internet faces many challenges as a bearer network: a large volume of information exchange, multi-level QoS and smoothly switching multiple access protocols. The Internet should be able to provide a variety of network capacity in a more dynamic and on-demand way, not just only limited network resources provision through virtualization. The elastic network is expected to adapt to network changes by enabling network protocols selection and combination dynamically. Cloud computing illustrates a new Internet-based model of IT resources (hardware, software, data) provision, delivery and consumption as a service. Therefore, network protocols as a service can provide guaranteed quality of service and good quality of experience to users who do not care about any network configuration and network management. In this paper, we proposes a novel idea of network capacity on demand by combining the service provision model of cloud computing with the openness of the network protocol. The related conception and stakeholders of network protocol as service are depicted. Cloud-based network architecture is design to present the provision, delivery and consumption of network capacity on demand and discuss the key features of cloud-based network. Finally, a prototype of cloud-based network is implemented by extending OpenFlow architecture.

As for the more and more severe corrosion fatigue of pipelines in service and the results of the former analyzing means and tests, a new method was brought forward to study the low-cycle corrosion fatigue by using a large pure-bended sample (480 mm×38 mm×12 mm). The experimental samples were obtained from the gas-transmission spiral welded pipe (X65) used in the west-east gas transport project of China. The experiential formula about crack growth speed, , is established via the experimental results under two different environments of air and 3% NaCl solution, and the two constants of a and b were identified.

Tow plug flow reactors were operated with municipal wastewater according to reversed A2/O process. The only difference was in sludge return ratio. Despite that more VFAs were consumed by denitrification, phosphate removal was enhanced rather than impaired by a higher sludge return ratio of 300%. It seems that higher phosphate removal can be achieved even more nitrate was reduced which means more carbon source consumption. This is contradictory with the well accepted enhanced biological phosphate removal (EBPR) theory, which regards sufficient volatile fatty acids in the wastewater as the indispensable premise. With less phosphate was released in the anaerobic zones, the final phosphate concentration in the effluent was lower when higher sludge return ratio was applied. The results indicated that neither carbon source nor phosphate release can directly determine phosphate uptake ability.

The shortest path between the start node and end node plays an important role in city’s road traffic network analysis system. The basic ant colony system algorithm which is a novel simulated evolutionary algorithm is studied to solve the shortest path problem. But the basic ant colony system algorithm is easy to run into the local optimum solution for shortest path. In order to solve the problem, the improved ant colony system algorithm is proposed. The improvement methods for selection strategy, local search, and information quantity modification of basic ant colony system are discussed in detail. The experiments are done in Beijing road network in China. The results of experiments show that comparing with the basic ant colony algorithm, the improved algorithm can easily converge at the global optimum for the shortest path.

This paper test to processing lakes sediment by three kinds of in-situ control technology which including aeration, zeolite capping and calcium nitrate in situ treatments, and it study the influence of phosphorus release from sediment. The test results showed: (1) under anaerobic conditions, the phosphorus release content is as 4.26 times as it under aerobic conditions. Under aerobic condition (dissolved oxygen saturation ≥ 20%), the Dissolved oxygen is not important for phosphorus release in sediments.（2）zeolite capping can effectively control the phosphorus release from sediment, but Dissolved oxygen is important for that. Under dynamic condition, the phosphorus release content is stability.（3）Under aerobic conditions or anaerobic conditions, calcium nitrate in situ treatments can effectively control the phosphorus release from sediment. Under aerobic conditions, the phosphorus release content reduce by 53.6%.Under anaerobic conditions, it reduce by 83.4%.(4) The control effects of the phosphorus release content by three kinds of in-situ control technology was followed: under anaerobic condition, calcium nitrate in-situ treatment > zeolite capping> untreated; and under aerobic condition, calcium nitrate in-situ treatment > zeolite capping > aeration ≥ untreated; and under hydrodynamic condition, calcium nitrate in-situ treatment >zeolite coverage>zeolite capping> aeration >untreated.

Cross-species amplification of twenty-five SSR loci from the DNA of five rhesus macaques of diverse regional origins was conducted using human primers for the polymerase chain reaction (PCR). Seven of these primer pairs, which consistently and unambiguously amplified polymorphic fragments from these five samples, were also used to amplify SSR loci for 111 Sichuan wild rhesus macaques of five different populations. The analysed microsatellite markers produced 109 alleles, varied from 4 to 16 alleles each locus. The number of alleles per population ranged from 6.79 to 11.38. Polymorphic information content showed that all seven loci were highly informative (mean = 0.9017±0.0166, >0.5). The average observed heterozygosity was less than the expected (mean = 0.6795 and mean = 0.8559, respectively). Genetic differentiation among the populations was considerably low with the overall and pairwise FST values (mean = 0.0375), and showed fairly low level of inbreeding (indicated by a mean FIS value of 0. 0.1991). Maintaining genetic diversity is a major issue in conservation biology. In comparison to other captive Macaca mulatta studies, these wild rhesus macaque populations showed a relatively high level of genetic diversity, and there was low gene flow among these populations. Careful genetic management is important for maintaining genetic variability levels. None of the seven informative loci are linked which screened in this study can be applied in future studies on population and conservation genetics of natural primate populations.

The rhesus macaque (Macaca mulatta) is perhaps the most widely distributed nonhuman primate, is used more extensively than any other primate species as animal models for the study of biomedicine. In this study, we sequenced and analysed a fragment of 491 bp of mitochondrial DNA (mtDNA) partial control region in 230 individuals belonging to 8 populations of Sichuan province of China. Among the 230 individuals, we observed 56 different haplotypes defined by 110 polymorphic sites. The average number of nucleotide differences (k) was 18.844, indicating that very high genetic differentiation and the extant Sichuan wild rhesus macaques population consists of diverse genetic groups in their maternal lineage. The mtDNA haplotypes of these Sichuan wild rhesus macaques clustered into two main clades (CladeⅠand Clade Ⅱ), may correspond toM. m. vestitusandM.m.lasiotis.

The dimension synthesis of crank rocker mechanism used in torque exciter was carried out with known angular displacement of rocker swing. Optimization method based on minimum kinetic energy of whole mechanism was adopted under constraint condition of minimum transmission angle and mechanism bar existence condition. Optimization design function was applied in solution and a design method of crank rocker mechanism was developed. The torque exciter has been in operation, achieving scheduled function for dynamic performance test, and all testing data are exact and valid.

Due to increasing water scarcity, reclamation and reuse of the secondary effluent of wastewater treatment plant are widely concerned in many countries. Before reuse, the residual contaminant in the secondary effluent should be further removed to guarantee safe reuse. Coagulation/sedimentation and subsequent chlorine dioxide(ClO2) disinfection was adopted for tertiary treatment of secondary effluent. Selection of coagulant and optimization of tertiary treatment parameters were performed in this study. The results showed that coagulation could remove turbidity and total phosphours(TP) effectively. Polyaluminium chloride(PAC) was the most suitable coagulant. The optimal coagulation condition was as follows: PAC dosage of 10mg/L(measured as Al3+), reaction time of 20 min, settling time of 40 min, in this case, the average removal rate of turbidity, color, UV254, TP and TOC could reach to 58.2%, 22.8%, 18.2%, 60.6% and 22.2%, respectively. ClO2could inactive bacteria andE. colieffectively. ClO2could further remove UV254, color and TOC. In case of ClO2dosage of 5mg/L, the sterilization efficiency could reach 100%, and the removal rate of UV254, color and TOC was higher than 25%, 70% and 25%, respectively. In the optimal condition, the removal efficiency of residual contaminant by the combination process was as follows: UV254of 45.9%, color of 76.5%, TOC of 66.7%, turbidity of 61.9% and TP of 96.3%.

The compressional strength of sea ice is a key parameter to determine the interaction between ice cover and offshore structure. In this study, the discrete element model (DEM) with particle bonding function is adopted to model the sea ice compressional strength. The bonding strength is set as a function of the ice temperature and ice salinity, and their influences on sea ice compressional strength are observed. The simulated results are compared well with the physical experimental data. With the improvement of this DEM, the ice load and ice-induced vibration of offshore structure can be simulated.

Cloth media filter was applied in the treatment of the effluent of a municipal wastewater plant through pilot scale test for water reuse. Ferric chloride (FeCl3), PAFC and polyaluminum chloride (PAC) were employed as coagulants respectively to carry out the test. The average removal efficiency of TP and CODCr was 28.76% and 8% after cloth media filter without coagulation, and TP removal was influenced by the influent water quality. However, precoagulation with coagulants of ferric chloride, PAFC, PAC, the average removal efficiency of TP was 63.58%, 60.13%, 66.94% respectively, and no influence of TP removal can be found by the influent water quality. The average removal efficiency of CODCr was increased to 17.7%、26.3% and 27.7%，SS was 70.7%、64.3% and 49.1%. TN and NH3-N were removed unstably after cloth media filter.

Due to increasing water scarcity, appropriate technologies were need for advanced treatment of wastewater to enable reuse. Effect of iron-carbon internal electrolysis in tertiary treatment of wastewater was investigated in this study. Static experiment was adopted to evaluate influence of Fe/C ratio, pH, reaction time and aeration on pollutant removal by iron-carbon internal electrolysis. Then dynamic experiment was conducted to determine removal rate of CODcr, TP, chroma and NO3--N. The results showed that internal electrolysis could remove CODcr, TP and chroma efficiently. The optimal ratio of Fe/C was 1:1. Initial pH could affect removal efficiency. In acid circumstance, the removal rate was higher. Degradation reaction by internal electrolysis was fast. when the reaction time was 10min, the removal rate could be ideal. In the process of internal electrolysis, aeration could increase pollutant removal rate. In aerated system, when the reaction time was only 15min, removal rate of CODcr, TP and chroma could reach 49.2%, 89% and 75%. But in non-aerated system, only when the reaction time was 100min could removal rate of these indexes reach 46.5%, 81% and 85.1%. In dynamic experiment, removal rate of CODcr, TP, chroma and NO3- could reach above 40%, 90%, 75% and 20%, respectively.

Sludge reduction by electrolysis and its subsequent influence on removal rate of COD, NH3-N, PO43- and on the sludge activity in the aeration tank were investigated. In this research, two parallel sequencing batch reactors were used with one set was operated in convention modality and the sludge of the other set was electrolyzed and then fed back to the reactor. The results showed that: sludge electrolyze could reduce the sludge production around 21% and had slight effect on substrate removal efficiency. After the sludge being electrolyzed, removal rate of COD and NH3-N decreased by 1.1% and 6.9%, respectively. PO43- removal rate increased by 6.1%. The number of protozoa, metazoan and protonema decreased and the structure of sludge floc became more compact. Moreover, the activity of microorganism and carbon source metabolism of sludge changed slightly, but the microbial community structure and metabolic function of microorganism had little change.

The metabolic activity of sludge samples taken from two pilot scale activated sludge reactor was studied. The two reactors were of the same size and structure. One was operated according to the reversed A2/O process (R-reactor) and another was operated according to conventional A2/O process (C-reactor). The activities of dehydrogenase (DHA) and electron transport system (ETS) and the specific oxygen uptake rate (SOUR) of sludge taken from R-reactor were 34.98%, 22.44% and 12.70% higher than those of the sludge taken from C-reactor. As for the R-reactor, the sludge undergoes aerobic condition right after anaerobic experience. Compared to entering aerobic stage from anoxic stage (C-reactor), entering aerobic stage from anaerobic stage can significantly enhance the activity of microbes, accelerate the decomposition of organics and improve the SOUR of the sludge.

The phosphorous removal behaviors under higher and moderate organic loading and after different durations of anaerobic stages were studied in the reversed A2/O process. Under both loading, the length of anaerobic stages did not significantly affect the subsequent aerobic phosphorus uptake efficiencies. Under higher loading, the available carbon sources are adequate, prolonging anaerobic stages led to more released phosphorus from phosphate accumulating organisms (PAOs). However, the phosphorus uptake rate in aerobic stage was almost the same as that of lower loading. At an anaerobic reaction time of 2.0 h, the corresponding specific aerobic phosphorus uptake rate achieved the highest value (6.13 mg/(L.h)). These results can help to determine the anaerobic hydraulic retention time in the reversed A2/O process.

This study aims to investigate laser welding process for the bonding of micro-fluidic devices. PMMA was selected for the investigation. The devices consist of an opaque substrate with micro-channels and a transparent cover. The welding process was optimized according to laser power, welding speed and clamping pressure. The cross-sectional analysis, flow and pressure tests, as well as the lap-shear test were conducted on the samples welded with the optimized process parameters. The results show that the laser welding can meet the requirements for bonding the plastic micro-fluidic devices.