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This review discusses the application scenarios of the machine learning-supported performance prediction and the optimization efficiency of tunnel boring machines (TBMs). The rock mass quality ratings, which are based on the Chinese code for geological survey, were used to provide “labels” suitable for supervised learning. As a result, the generation of machine prediction for rock mass grades reasonably agreed with the ground truth documented in geological maps. In contrast, the main operational parameters, i.e., thrust and torque, can be reasonably predicted based on historical data. Consequently, 18 collapse sections of the Yinsong project have been successfully predicted by several researchers. Preliminary studies on the selection of the optimal penetration rate and cost were conducted. This review also presents a summary of the main achievements in response to the initiatives of the Lotus Pool Contest in China. For the first time, large and well-documented TBM performance data has been shared for joint scientific research. Moreover, the review discusses the technical problems that require further study and the perspectives in the future development of intelligent TBM construction based on big data and machine learning.

Under the joint action of dynamic and static loads, the connecting bolts of the top cover of the pump turbine are prone to cumulative damage in local areas such as threads, resulting in cracks or development, and fatigue fracture may occur in severe cases, which will cause serious safety accidents. Therefore, it is necessary to carry out accurate fatigue life estimation analysis for connecting bolts, which has always been a hot spot and difficulty in the industry. This paper introduces several commonly used fatigue life analysis methods of parts, combined with the force characteristics and structural characteristics of the connecting bolts of the top cover, and analyzes and discusses the fatigue life analysis methods suitable for the top cover bolts. Finally, it is believed that the application of stress-strain field strength method can better describe the actual state of the bolt danger area, and the current damage state has an influence on the amount of damage generated by further loading, and the fatigue life analysis of connecting bolts can be combined with the stress-strain field strength method and variable damage linear cumulative damage theory, and the fatigue life and residual fatigue life can be estimated in the design stage or after the phased service of the bolt.

The performance of a recycling process for CO2capture and utilization of exhaust gas in the steelmaking plant was reported. A facility capable of capturing CO2at 3200 m3/h was established in the steelmaking plant, resulting in the CO2production of 50,000 t/a. The CO2concentration of the exhaust gas from the lime kiln increased from 25.0 to 99.8 vol.% using the comprehensive method of the pressure swing adsorption and cryogenic separation. The captured and purified CO2was successfully applied in the converter process by the top blowing and bottom blowing. The utilization of CO2was 3.5 m3/t through these two modes. After optimizing parameters of CO2–O2mixed top blowing, the value of [C] × [O] and the content of TFe in slag were reduced by 1.33 × 10−4and 1.27%, respectively, and the dephosphorization rate of the molten steel increased by 2.31%. For the CO2bottom blowing, the [N] content in the molten steel was significantly reduced by 5.7 × 10−6.

Objective:Diabetic foot ulcers (DFUs) are one of the most serious diabetic consequences, leading to amputations. Various therapies have been used to treat DFUs; however, a combination of negative pressure suction, artificial skin and autogenous skin implantation have never been investigated. This study aimed to evaluate the effectiveness of a novel three-step therapy protocol using negative pressure wound therapy (NPWT), artificial skin and autogenous skin implantation in patients with DFUs.Method:At a single tertiary university hospital between 2015 and 2018, the three-step therapy protocol was applied to patients with DFUs and its safety and efficacy was investigated.Results:A total of 21 patients took part in the study. The majority of the patients were female (62%), with a mean age of 65 years and a mean body mass index of 21kg/m2. A third (n=7) of operative sites experienced minor complications, with two requiring re-operation. At a median follow up of 24 months, the average time of complete wound healing was 46 days, and the wound healing rate was 71%. The first-stage wound healing rate was 90%. All patients had achieved remission without any further recurrence of disease.Conclusion:This comprehensive surgical technique for managing DFUs achieved a high local cure rate, minimal functional morbidity, and acceptable wound complication rates. The three-step therapy protocol has the potential to promote the healing process of DFUs, which is expected to serve as a new method for the treatment and cure of DFUs.

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivoefficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)) two-target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivoefficacy compared to triantennary GalNAc-conjugated siRNAs.

AbstractWhile excavated discharge channels are often used for the emergency treatment of landslide-dammed lakes, the erosion of the discharge channel of a landslide dam is complex and rarely monitored on site. This work presents a quantitative monitoring method based on three-dimensional terrestrial laser scanning technology (TLS) for analyzing the erosion of a landslide dam discharge channel and then applies this method to evaluate the emergency engineering treatment of the 2018 Baige landslide-dammed lake in 2019. The proposed method uses TLS technology to accurately track the dynamic evolution of the discharge channel and to quantify the lateral erosion. Moreover, qualitatively analysis for vertical erosion is conducted based on the difference between actual and hypothetic river elevation. The results indicate that erosion processes of landslide deposition fluctuate as the results of flow discharge variations. Damage to the covering layer consisting of large particles is considered to be the main cause of this phenomenon. According to the relationship between erosion intensity (EI) and flow velocity, an empirical formula is deduced for erosion analysis. The key parameter in this formula is determined by the variation rate of discharge, the flow velocity, the composition of riverbank and the flow field distribution.

To study the antipyretic and anti-inflammatory constituents from the active fraction of Reduning (RDN) Injection.

Direct conversion of the readily available alkyl bromides and alcohols to value-added epoxides using dimethyl sulfoxide (DMSO) under mild reaction conditions has been developed. Benzyl and allyl bromides, and activated and unactivated alcohols all proceeded smoothly to give epoxides in high to excellent yield. Dimethyl sulfide, generated by DMSO oxidations, was in situ elaborated to form the substituted dimethyl sulfonium ylide species that participates in the Corey–Chaykovsky epoxidation in a domino and one-pot fashion, respectively.

ABSTRACTThe reoxidation of molten steel by oxidising slag directly affects the molten steel cleanliness. There is a good relationship between molten steel cleanliness and the defect sources of cold rolled sheets. The results show that there is a direct relationship of the slag composition to steel cleanliness and the rate of surface defects on the final products. The thermodynamic calculations show that the activity of iron oxide decreases with the increase of w(CaO)/w(Al2O3) specifically when the content of T.Fe in slag remains at lower levels. In order to enhance the absorption ability of the slag to Al2O3inclusions, w(CaO)/w(Al2O3) should be controlled in the range of 1.0–1.4 in the liquid region of slag when T.Fe content in RH final slag is less than 6 mass%. By reasonable control of T.Fe content and w(CaO)/w(Al2O3) in the slag, the defect content of sheets significantly declines.

In this paper, the effect of rare earth elements on the behavior of inclusions for low-alloy structural steel production was studied. The results showed that adding rare earth elements after different refining processes had a great impact on the results: (1) When adding rare earth elements after the LF furnace process, the alloy yield was low, and the rare earth inclusions was rare, the pure and coexisted inclusions of rare earth (La & Ce) were found; (2) While added after the RH furnace process, the alloy yield and the amount of rare earth inclusions increased greatly, but only coexisted inclusions of rare earth (La & Ce) were found. Furthermore, the precipitates of Nb and the contents of Al and Mg in the inclusions were also sharply reduced, which indicated that the rare earth element had obvious effect on the denaturation of the inclusions.

Helicobacter pylori(H. pylori) colonizes the stomach epithelium of half the world's population and is responsible for various digestive diseases and even stomach cancer. Vaccine‐mediated protection against H. pyloriinfection depends primarily on the specific mucosal and T‐cell responses. In this study, the synthetic lipopeptide vaccines, Hp4 (Pam2Cys modified UreB T‐cell epitope) and Hp10 (Pam2Cys modified CagA T/B cell combined epitope), not only induce the bone marrow derived dendritic cells (BMDCs) maturation by activating a variety of pattern‐recognition receptors (PRRs) such as Toll‐like receptor (TLR), Nod‐like receptor (NLR), and retinoic acid‐inducing gene (RIG) I‐like receptor (RLR), and but also stimulate BMDCs to secret cytokines that have the potential to modulate T‐cell activation and differentiation. Although intranasal immunization with Hp4 or Hp10 elicits robust epitope‐specific T‐cell responses in mice, only Hp10 confers protection against H. pyloriinfection, possibly due to the fact that Hp10 also induces substantial specific sIgA response at mucosal sites. Interestingly, Hp4 elevates the protective response against H. pyloriinfection of Hp10 when administrated in combination, characterized by better protective effect and enhanced specific T‐cell and mucosal antibody responses. The results suggest that synthetic lipopeptide vaccines based on the epitopes derived from the protective antigens are promising candidates for protection against H. pyloriinfection. The self‐adjuvanted lipopeptide vaccines Hp4 and Hp10, obtained by chemical conjugation of Pam2Cys to H. pyloriepitopes, can activate dendritic cells (DCs) and induce specific cellular immune responses. Hp10 but not Hp4 simultaneously induces mucosal immune responses and further confers protection against H. pyloriinfection. Lipopeptide‐based vaccine could be considered as a profitable toolkit for future treatment of H. pyloriinfection.

Three unusual sesquiterpenoid dimers, nardochinoids A–C (1–3), were isolated from Nardostachys chinensisBatal. Compound 1features a rare fused 3,8-dioxatricyclo[7.2.1.01,6]dodecane-11-one ring system, compound 2is the first nitrogen-containing nornardosinane–aristolane sesquiterpene conjugate, and compound 3represents the first example of the dimer of a nornardosinane and a nardosinane sesquiterpene. Their structures were characterized by NMR spectroscopic methods and X-ray single-crystal diffraction analysis. Compound 3showed significant anti-inflammatory activities.

The multilayer drift chamber (MDC) is one of the key detectors at the BESIII, which is mainly responsible for the precise measurement of charged particles. High reconstruction efficiency of charged particles with a wide range of momentums is a basic requirement for the MDC reconstruction software. The purpose is to improve the tracking efficiency at the low transverse momentum region. The Hough transform is a mathematical method that can map hits in a detector to parameter space to find tracks globally. In this paper, we have used it as the basis for developing a new tracking algorithm to find tracks in MDC. In addition, the drift distances of hits are considered when implementing Hough transform. This tracking algorithm is implemented in the BESIII offline software system, and its performance is checked using both Monte Carlo and data. The results show that this tracking method improves reconstruction efficiency at the low transverse momentum region. The tracking algorithm based on Hough transform is proved to be beneficial for the MDC low transverse momentum tracking, and has been used in BESIII offline data reconstruction

The concentration of total nitrogen (TN) is reported to vary between 20 and 35 mg/L in domestic wastewater. In raw wastewater, ammonia nitrogen (NH4+-N)is the main nitrogen form, accounting for 70%–82% of the TN concentration. Organic nitrogen, nitrite nitrogen (NO2−-N), and nitrate nitrogen (NO3−-N)are present as well. For years, due to the lack of regulatory limits on nitrogen concentration in surface waters, nitrogen from secondary effluent has posed a significant threat to the health of aquatic ecosystems. Researchers have made substantial efforts to reduce the nitrogen concentration in secondary effluent. As a kind of advanced wastewater treatment technology, the subsurface infiltration (SI) system has been widely used, owing to its advantages, which include low operation cost, easy maintenance, and low energy consumption. This review discusses the fate of various forms of nitrogen in SI treatment, including organic nitrogen, NH4+-N, NO2−-N, and NO3−-N. Major biological processes involved in nitrogen removal and the main factors influencing its transformation are suggested. Finally, it is shown that ammonification followed by nitrification-denitrification plays a major role in nitrogen removal. Further research needs to focus on the emission characteristics of gaseous nitrogen (generated from the nitrification, denitrification, and completely autotrophic nitrogen-removal over nitrite (CANON) processes) with respect to their greenhouse effects.

In order to improve the accuracy of the selection on rock mechanical parameters, the relation between uniaxial compressive strength (UCS) and physical mechanical parameters should be investigated. A great number of physical and mechanical tests on rock in the first-stage of Guangxi Fangchenggang Nuclear Power Plant (GFNPP) are conducted. Mineral identification tests of rocks are conducted, and rocks are divided into two groups (A and B) according to the result of the test. The correlation coefficient between rock UCS and rock physical parameters (porosity, density and P-wave velocity) are calculated by using Pearson’s analytical method. The result shows that the relationship between physical parameters and mechanical parameters of rock is influenced significantly by content of quartz. Regression analysis method is used to explore the relation between UCS and porosity, density, P-wave velocity of rock; combined with the dimensional analysis, the relation between UCS and rock physical parameters was established. Based on normality test and randomness test, the best fitting equation is determined as the empirical equation of UCS. The empirical equation was used to forecast the UCS of rock in the second-stage of GFNPP, comparative results show that the forecasting value and the experimental value are in good agreement.

In order to improve the accuracy of the rock mechanical parameters, the correlations among physical and mechanical parameters were investigated. A large number of laboratory testing results curried out on 408 rock specimens including metamorphic rocks, sedimentary rocks and igneous rocks. Through the statistical analysis of the laboratory test data, several regression equations among rock material parameters were established. The research suggests that, in addition to Poisson's ratio, the mechanical parameters (unconfined compressive strength (UCS), elastic Young’s modulus, shear modulus) relate well to physical parameters (porosity, P-wave velocity), and the relationships are mainly described by power and exponential correlations which have good squared regression coefficients. The correlation between elastic Young’s modulus and dynamic elastic modulus was established, as well as the relationship between shear modulus and dynamic shear modulus.

The novel solid NaXe nanoclusters were prepared. Measurements and calculations indicated that solid NaXe nanocluster has easily vibration- dissociated ground state and stable excited state to emit UV radiation. In the meanwhile the solid nanocluster NaXe retains fcc position within the host NaCl matrix. Therefore，the integrated ultraviolet(UV)-micro-excimer-laser-matrix can be prepared by using solid NaXe nanoclusters.

This review summarizes the research outcomes and findings documented in 45 journal papers using a shared tunnel boring machine (TBM) dataset for performance prediction and boring efficiency optimization using machine learning methods. The big dataset was collected during the Yinsong water diversion project construction in China, covering the tunnel excavation of a 20 km-section with 199 items of monitoring metrics taken with an interval of one second. The research papers were the result of a call for contributions during a TBM machine learning contest in 2019 and covered a variety of topics related to the intelligent construction of TBM. This review comprises two parts. Part I is concerned with the data processing, feature extraction, and machine learning methods applied by the contributors. The review finds that the data-driven and knowledge-driven approaches in extracting important features applied by various authors are diversified, requiring further studies to achieve commonly accepted criteria. The techniques for cleaning and amending the raw data adopted by the contributors were summarized, indicating some highlights such as the importance of sufficiently high frequency of data acquisition (higher than 1 second), classification and standardization for the data preprocessing process, and the appropriate selections of features in a boring cycle. The review finds that both supervised and unsupervised machine learning methods have been utilized by various researchers. The ensemble and deep learning methods have found wide applications. Part I highlights the important features of the individual methods applied by the contributors, including the structures of the algorithm, selection of hyperparameters, and model validation approaches.

Mono-like silicon is one of the promising alternative wafer materials compared with mono-crystalline silicon and multi-crystalline silicon due to its relatively higher conversion efficiency and lower production cost. But there is still a large room to improve the crystal quality and to reduce the manufacturing cost, which could push the wafers into photovoltaic industry practically. In this paper, the CGSim software has been employed to analyze the influence of heater diameter on the temperature distribution and melt convection in a mono-like silicon lab-scale growth system. The results showed that the power consumption of the furnace was decreased from 65.2KW to 52.8KW as decreasing the heater diameter. It is mainly caused by the improved heating efficiency of resistance heater. At the same time the average melt temperature and temperature difference along axial direction as well as along melt free surface were increased with decreasing the heater diameter, resulting in a change of melt convection behavior. Consequently, the shape and fluctuation of solid-liquid interface changed due to various convection intensity and temperature difference. Thus, aiming at decreasing product cost and improving wafer quality, the optimized distance between heater and graphite crucible for mono-like silicon growth system could be determined as 20mm.

Negative temperature coefficient (NTC) ceramics with general composition Ni0.6Mn2Si0.4-xAlxO4 (0≤x≤0.04) were prepared by conventional solid-state reaction method and were investigated for cationic distribution and electrical properties. X-ray diffraction (XRD) confirmed that the Si cations occupied the tetrahedral site. The valence states of Mn ions were characterized by X-ray photoelectron spectral (XPS). The results showed that Mn4+ content decreased from 0.19 mol to 0.185 mol when the Si molar content declined from 0.4 to 0.1, i.e. the content of Mn4+ was 0.197mol when x was equal to 0.4. Besides, the resistivity (ρ25) reached the minimum value when the Si molar content was 0 (ρ25=4.07×104Ω·cm).

Capacitive deionization (CDI) is a water desalination technique in which salt ions are removed from brackish water by flowing through a spacer channel with porous electrodes on each side. Upon applying a small voltage difference between the two electrodes, cations move to and are accumulated in electrostatic double layers inside the negatively charged cathode and the anions are removed by the positively charged anode. Therefore, one of the advanced merits of CDI is the low driven energy by compared to other desalination technologies. Inspired this, we have performed the calculation on energy consumption of activated carbon based CDI in different operation conditions. The results show that the energy consumptions are significantly related to cell voltage as well as solution concentration. Furthermore, the round trip efficiency as a vital indication in terms of energy consumption have been introduced and discussed as well.

AbstractThe removal abilities in subsurface wastewater infiltration system (SWIS) rely heavily on the metabolism of microorganisms. Although the role of microorganism is appreciated, a lack of effective indicators of microbial function in SWIS is apparent. This study explored the correlations between oxidation-reduction potential (ORP) and microorganism and enzyme activities involved in nitrogen removal processes. The results showed that SWIS exhibited a gradual change in ORP level, microbial activity, and abundance along the soil profile. The quantities of nitrifier and denitrifier were in positive correlations with potential nitrification activity and denitrification activity (p < 0.05). The correlation equations for ORP and nitrate reductase (NAR) activity were N = 1250 ORP—65.125 (R2 = 0.6165, p < 0.05), N = 333.3 ORP—21.27(R2 = 0.7508, p < 0.05) from the horizontal and longitudinal directions, respectively. The results suggested that ORP level could be used as an indicator of key functional microorganism and NAR activity involved in nitrogen cycling of SWIS. Furthermore, the distribution of ORP and aqueous rate behaved in the opposite way, confirming the running mechanism of SWIS theoretically.

Bottom blowing has a significant influence on the stirring of molten steel in a combined blown converter. The effects of flow rate and configuration of bottom blowing tuyeres on the flow of molten steel inside the converter were studied with Eulerian multiphase model by using commercial software Fluent6.3, then the bottom blowing system was optimized based on the numerical simulation. The results show that the shape of the flow field of gas-steel phase zone is like an inverted cone, forming a strong center circulation and a weak circulation near the wall on both sides of the gas column because of bottom blowing. The average velocity of molten steel increases with the increase of bottom blowing flow rate. The flow pattern of molten steel changes little when the pitch circle diameter of bottom blowing tuyeres configuration changes. The molten steel has a good dynamic condition when the bottom blowing tuyeres are distributed at 0.55D(Dis the diameter of the converter bottom) of the converter bottom. The simulation results were verified by industrial experiments.

J55 steels are mainly used in the field of petroleum casing due to their excellent mechanical properties. Microstructure of J55 can improve its impact properties without losing strength. The characteristics of MnS inclusions including composition, morphology, size, mumber and area with different S content and Ca/S ratio in plates were studied utilizing SEM-EDS (scanning electron microscopy-energy dispersive spectrometry) and ASPEX. The effects of inclusions characteristics and molten steel compositions on impact properties were also investigated. The results demonstrate that inclusions affecting impact properties are mainly massive string typed MnS, especially those with size larger than 90 μm. Moreover, the number density and area density of MnS inclusions also have effect on the impact properties. The impact properties of steel are obviously improved by controlling S content to less than 0.004 0 mass% or Ca/S ratio more than 0.5 in plates, which ensures that the generation of larger size MnS inclusions is effectively inhibited and the number of MnS inclusions is reduced.

This paper presents a seismic method and a newly developed device to predict the hazardous geological zones ahead of a tunnel face. The equipment used to predict hazardous geological zones consists of three components: the seismic source, the acquisition unit, and the data processing unit. The following features enable this device to be a valuable tool in predicting hazardous geological zones: the precise trigger time detection; the application of semi‐liquid couplant, which improves geophone coupling with the surrounding rock; the filtering of the prominent tunnel acoustic wave interference; and a software package of information on hazardous geological zones. Through extensive detection exercises of hazardous geological zones in the excavations of nearly 100 tunnel projects in China, it has been demonstrated that this device can satisfactorily predict hazardous geological zones, such as faults, water‐bearing zones, karst caverns, etc., within 150 m in front of the tunnel faces.

In high mountain and deep river valley areas, geological materials of river valley evolution are often missing or incomplete. To address this problem, tectonic movements at project site are analyzed using mathematical statistics based on the analysis of formation and evolution history of river terraces, and then a new method to determine the thickness of river incision layers is proposed. Taking Jiata dam area at the Western Route of South-to-North Water Transfer Project in China for an example, the reliability and reasonability of the proposed method are validated through a case study.

During the resistance spot welding quality control process, the traditional quality control methods can’t compensate all the affecting factors effectively. By welding 316LVM stainless steel wire to the surface of sheet of the same material, three kinds of process parameters, including electrode voltage, dynamic resistance and electrode displacement which affected by many affecting factors during the spot welding process were measured and analyzed. The results show that, by comparing with the process parameters during the normal situation, the dynamic change of the these process parameters during different stage appears distinguishable characteristics, these characteristics would supply a research basis for recognizing whether the affecting factors exist.

Design and construction of pile foundation in seaside zone face the specific geotechnical conditions. The in-situ geotechnical tests need to be conducted. The quality feature of the piles is assessed according to the results of in-situ small strain test, coring test and pile stress test. For different depth of rock and soil stratum and pile bearing layer, the trial pile stress distribution results and follow-up stress and settlement monitoring provide engineering parameters for design and pile-driving.

A reliable and sensitive liquid chromatography-ion trap-time of flight tandem mass spectrometric assay (LCMS-IT-TOF) coupled with accelerated solvent extraction (ASE) was developed to identify and quantify six typical heterocyclic aromatic amines (HCAs), including 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-9H-pyrido[2,3-b]indole (AαC) and 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC) in cooked meat products. The effects of various experimental factors on separation and detection were investigated, and the fragmentation patterns of six HCAs were discussed. The method has shown high reproducibility with intra-day and inter-day precision (RSD, %) less than 6.16% across three quality control levels for the six analytes. The assay was linear over the concentration range of 10 to 1000 μg L−1for IQ, MeIQ and 5 to 500 μg L−1for MeIQx, PhIP, AαC and MeAαC (r2≥ 0.996). The experimental results showed that the proposed method can be used successfully to identify and determine six typical HCAs at ultra-trace levels (μg kg−1) in cooked meat products.

In order to enhance the hydraulic loading rate (HLR) of a subsurface wastewater infiltration system (SWIS) used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results show that the intermittent operation mode contributes to the improvement of the HLR and the pollutant removal rate. When the wetting-drying ratio (RWD) was 1.0, the pollutant removal rate increased by (13.6 ± 0.3)% for NH3-N, (20.7 ± 1.1)% for TN, (18.6 ± 0.4)% for TP, (12.2 ± 0.5)% for BOD, (10.1 ± 0.3)% for COD, and (36.2 ± 1.2)% for SS, compared with pollutant removal rates under the continuous operation mode. The pollutant removal rate declined with the increase of the HLR. The effluent quality met The Reuse of Urban Recycling Water – Water Quality Standard for Scenic Environment Use(GB/T 18921-2002) even when the HLR was as high as 10 cm/d. Hydraulic conductivity, oxidation reduction potential (ORP), the quantity of nitrifying bacteria, and the pollutant removal rate of NH3-N increased with the decrease of the RWD. For the pollutant removal rates of TP, BOD, and COD, there were no significant difference (p < 0.05) under different RWDs. The suggested RWDwas 1.0. Relative contribution of the pretreatment and SWIS to the pollutant removal was examined, and more than 80% removal of NH3-N, TN, TP, COD, and BOD occurred in the SWIS.

Test by establishing different embankment flowing systems studied the combination of different substrates and different plants purification efficiency and the effect on the stability of the efficiency of the flowing system. Results show that, the mixed matrix(loess, sand and brown loam) is more efficiency than the single matrix, especially for suspended solid (SS), ammonia (NH3-N), total phosphorus (TP) removal, the removal rate is over 60%. Tall fescue (Festuca elata Keng ex E. Alexeev) is more suitable for the flowing system than perennial ryegrass (Lolium perenne L.). And, long running of the system is possible.

Under the laboratory condition, use the mixture of coal cinder and soil, the mixture of fine sand and soil , and simple soil as the matrixes; use the Acorus calamus, the Typha angustata Bory et Chaub, and the Scirpus validus Vahl as the plants. Three groups of ditch systems are built to study the effect of different group of ditches in removing nitrogen and phosphorus pollution of paddy fields drainage ditch. The results show that the plants significantly improve the purification performance of ditches, the removal rate to TN of the ditch system based on the mixture of fine sand and soil and the Acorus calamus is 50.9% which is higher than other groups; the removal rate to TP of the ditch system based on the mixture of coal cinder and soil and the Acorus calamus is 48.1% which is higher than other groups.

Theory of the safety ergonomics and reliability analysis was applied in this paper. Influences of port handling machinery and workers on the handling reliability were studied. For the general cargo handling process, mathematical model was put forward. According to the model, calculations were carried out to increase the working efficiency of the port handling machinery. At same time, combined with port investigation and factors affecting the operation of workers, measures were proposed to improve the safe and efficient production of the port.

Degradation of polycyclic aromatic hydrocarbons (PAHs) and microbial quantity were investigated in aged PAHs-contaminated soil in a pot experiment with regrass and alfalfa. After 60 days germination the concentration of total PAHs in soil decreased by 37.57% and 38.41% with the treatment of ryegrass-microbe agent and alfalfa-microbe agent. The processes of ryegrass and alfalfa were 18.72% and 19.34%. The root system promoted the quantity of microbe and the microbial agent was benefit for the PAHs degrading microbe. And there was significant positive correlation between the number of PAHs degrading microorganisms and the removal rate of PAHs in the soil.

Pb, Cd contamination is a serious enviroment problem in the process of exploitation and utilization of zinc mine. In this study, the contents and different fractions of Pb, Cd were investigated in a regions of zinc smelting with indigenous method. The results revealed that Pb, Cd pollution were seriously in smelting slags and farmland. The contents of Pb, Cd were 34 times and 9 times as that of the background values of soil. The sequential extraction test showed that 80% of Pb were associated with residual Pb, Fe-Mn oxides bound Pb and Organic bound Pb, while exchangeable fractions Pb was quitely lower.The sequence of Cd fracttions in slags was residual fraction>Fe-Mn oxide-bound>Exchangeable> Carbonate-bound > Organic-bound. The exchangeable fraction Cd in farmland soils was the most and reached 24%~43%. Bioavailability of Cd is very high in the studied area and had huge threat to the crop security and human healthy.

Oxidation Reduction Potential (ORP) is one of the most important factors that not only influences the operation of subsurface wastewater infiltration system (SWIS), but also has a crucially effect on treatment efficiency and the environment of microbial. Therefore, this paper briefly analyzes the effects of ORP measures which are commonly used to improve ORP, such as flooding and drying alternate, constituting matrix, diffluent ratio, oxygen recovery by inflow pipes and roots of plants and soil animal activity , are summarized. Example analysis shows that all measures mentioned are practicable. With the deepening study of the technology, more attention will be paid on combining a series of different methods and applying new matrix materials for developing SWIS theory and research. The operation mode will be more flexible.

In order to quantitatively analyze the contents and distribution of the moveable oil in tight oil reservoir, this research has done experiment on 12 representative cores. The total moveable oil saturation is between 5.17% and 43.30%. And the big throat controls less contents of moveable oil than the small one, throat radius between 0.02μm~0.1μm plays the leading role, and nanometer throat controls most of the pore space of moveable oil. Comparing with permeability higher than 0.1mD, permeability between 0.03mD~0.1mD, permeability between 0.01mD~0.03mD, permeability lower than 0.01mD, the first one has the biggest content of the total moveable oil, and its moveable oil is mainly controlled by throat radius between 0.02μm~1.0μm, while the moveable oil of permeability between 0.01mD~0. 1mD reservoir is mainly controlled by throat radius less than 0.1μm, and the other reservoir is mainly controlled by throat radius between 0.02μm~0.05μm.

Considering the energy variation, cylindrical P-wave propagation across a linear elastic rock joint is analyzed. Then parametric studies are carried out to investigate the effects of the wave source distance,the joint stiffness and the incident waveforms on wave propagation across a jointed rock mass.

According to the displacement discontinuity method and the conservation of momentum at the wave fronts, analysis for cylindrical P-wave propagation across a linear elastic rock joint is carried out. Considering the energy variation for wave propagation in one medium, the wave propagation equation was derived and expressed in an iterative form. The transmission and reflection coefficients are then obtained from the equation. By verification, the results agree very well with those from the existing results.

Heavy metal contamination of soils is a widespread and serious enviroment problem in the process of exploitation and utilization of lead-zinc mine. In this study, the distribution, pollution index of lead, cadmium, zinc and copper of the soils near an abandoned zinc mine dump heaps were investigated. The results showed concentrations of Pb, Cd, Zn and Cu in smelting slags averaged at 11950mg/kg, 92mg/kg, 8878mg/kg, and 2129mg/kg respectively, whereas concentrations of heavy metal in adjacent soils exceed the maximum of soil environment. Pb and Cd are main pollutant. All the samples were heavy pollution by the assessment of single-factor pollution index and integrative pollution index. Hheavy metals next to the smelting slags mainly existed in the surface soil (0-20cm). Heavy metasl had lower ability of transforing downwards. The distribution characteristics of heavy metals in farmland was probably relateded to plowing processing, mixing fresh soil and the change of soil pH.

In order to evaluate the soil environmental quality of the north of the Guangdong Province, after a comprehensive research of the soil quality in the north of the Guangdong Province ,some analysis was been down for the characteristic of soil inorganic pollutants according to the soil test results. Refering to the standard of soil quality GB-15618-1995,making an evaluation for eight heavy metals (Cu,Pb,Zn,Cr,Cd,Hg,As,Ni). Single-factor index method and Nemerow comprehensive pollution index method were used in comprehensive assessment and classification of soil environmental quality in research area. The result shows that,the maximum of the single-factor index was Cd,the number is 1.71;the min number of the single-factor index was Hg,the number is 0.27;in regard to comprehensive pollution index,the average number is 1.94,according to the comprehensive pollution index,the soil environmental quality of study area was slightly polluted.

Substrate clogging in subsurface wastewater infiltration system (SWIS) is a significant problem that affects hydraulic capacity and operational performance. The mechanisms for substrate clogging were reviewed. The factors affecting substrate clogging were discussed as well. The strategy to ease and prevent substrate clogging phenomena was put forward.

In order to study the dynamic characteristics of centrifuge facility-vibration shaker system, In the establishment of centrifuge facility-vibration shaker system multi-body dynamic model based on virtual mocking technology, the virtual dynamic model of the entire centrifuge facility-vibration shaker system more close to reality is built up by the transmission of finite element of flexible centrifuge arm. This paper describes how to build the 3-D virtual prototype of centrifuge facility-vibration shaker system by using Pro/e and ADAMS software, and how to create the modal neutral file of the centrifuge arm by using ANSYS software. Considering the system as a rigid-flexible coupling system, the dynamical simulation is carried out, and the results are benefit for the further research of its kinetic behavior, dynamic and variable characteristics basis and the design of such system.

The High Performance Compact Reactor (HCR) was applied in the pilot plant, and the influence of jet volume, residence time and pollution loads on the pollutant removal efficiency was investigated. The results show that HCR system start operating faster processing Shale Oil Wastewater, 3.1m3 / h of jet volume was the best and the optimal residence time of 40min. At the same time, HCR process has stronger anti-shock loading capability and anti-pollution loading capability.