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To solve the problem of poor stability of additive flame retardant waterborne polyurethane， a series of waterborne polyurethane with flame retardant properties was synthesized by prepolymer method using aliphatic polyisocyanate， polyether polyol， and flame retardant phosphorus-containing polyol as raw materials. The flame retardant waterborne polyurethane was applied to the dipping process of microfiber synthetic leather base （microfiber base）. Its effects on the mechanics， quality， flame retardant， and thermal decomposition properties of microfiber base were discussed. The results show that with the increase of phosphorus-containing flame retardant polyol content， the combustion rate decreases from 115.00 mm/min to 60.79 mm/min， and the limiting oxygen index increases from 21.00% to 24.20%. After different concentrations of phosphorus-nitrogen flame retardants were sprayed on the surface of microfiber base， microfiber base appears self-extinguishing phenomenon during combustion， and the limiting oxygen index increases to 27.00%. Compared with the microfiber base without flame retardant treatment，the peak heat release rate and total heat release rate of the microfiber base after flame retardant treatment are reduced by 42.29% and 20.01%， respectively. The test analyses of SEM and Raman spectroscopy reveal that the graphitization degree of the carbon layer is improved and the surface structure becomes more compact after flame retardant finishing， suggesting that the flame retardant plays a crucial role by using the condensed phase flame retardant mechanism.

To address the challenges in tracking complex maneuvering extended targets, an effective maneuvering extended target tracking method was proposed for irregularly shaped star-convex using a Transformer network. Initially, the alpha-shape algorithm was used to model the variations in the star-convex shape. In addition, a recursive approach was proposed to estimate the irregular shape of an extended target by detailed derivation in the Bayesian filtering framework. This approach accurately estimated the shape of a static star convex extended target. Moreover, through the structural redesign of the target state transition matrix and the real-time estimation of the maneuvering extended target’s state transition matrix using a transformer network, the accurate tracking of complex maneuvering targets was achieved. Furthermore, the real-time tracking of star convex maneuvering extended targets was achieved by fusing the estimated shape contours with motion states. This study focused on constructing certain complex maneuvering extended target tracking scenarios to assess the performance of the proposed method and the comprehensive estimation capabilities of the algorithm considering both shapes and motion states using multiple performance indicators.

Superhydrophobicity and superhydrophilicity are extreme properties of solid surface governed by surface morphology and surface chemistry. Switching between superhydrophobicity and superhydrophilicity can be achieved by applying external stimuli and exchanging counterions due to the change in surface morphology and/or surface chemistry. This review mainly gives a concise overview of switchable wettability of surface. Through applying external stimuli such as light, temperature, pH value, solvent, electric potential and exchanging of counterions, the wettability of surface can switch between superhydrophobicity and superhydrophilicity. The material with asymmetric wettability exhibits some novel abilities such as directional liquid transport. Finally, the advances of surface with switchable wettability are prospected. By controlling the micro-nano structure and chemical composition, the switch between superhydrophobicity and superhydrophilicity can be realized on various surfaces.

The effect of the use of Aspergillus oryzae, lactic acid bacteria (LAB) and Wickerhamomyces anomalus as starter cultures on volatile substances during the fermentation of Douchi. The results showed that the contents of total volatile compounds in the uninoculated control, A. oryzae, LAB, A. oryzae + LAB, and W. anomalus inoculation groups were 5 145.88, 13 972.15, 9 006.07, 4 359.72 and 5 169.42 μg/kg, respectively. The contents of alcohols, organic acids, ketones and esters were increased by A. oryzae; the contents of alcohols and organic acids were increased by LAB; the contents of alcohols and organic acids were increased by the mixture of A. oryzae and LAB, but its effect was less pronounced than that of pure culture fermentation; the contents of alcohols and organic acids were increased by W. anomalus. Compared with the control group, the contents of pyrazines and phenolics in each inoculated fermentation group were decreased. Taken together, A. oryzae was the most suitable for the fermentation of Douchi, and the other strains could assist in regulating the production of volatile compounds during the fermentation of Douchi. Our findings from this study could provide some theoretical references for the industrial production of Douchi with traditional Chinese flavor.

Guizhou Province is located in Southwest of China, with many mountains and hills, and is a typical karst topography and geomorphology area with frequent geological disasters such as collapses and landslides. The existing dangerous rock mass in the Xiaotunyan collapse zone in Sinan County has large range and volume, and fissures, concave cavities, and solution caves have developed. Objective In order to study the failure probability of passive protection nets for rockfalls in typical karst areas. Methods A three-dimensional model of the collapse zone through high-precision realistic modeling technology was constructed, by which the movement process of collapsed falling rocks was simulated. According to the results of the field investigation, aerial photography of the unmanned aerial vehicle and numerical simulation, an appropriate rockfall location layout for the passive protection net was selected. And based on the identification of the rockfall particle size, the different rockfall particle sizes were selected to simulate the interception effect of the passive protection net, then the failure probability of the passive protective net can be calculated. Results The results show that the rockfall breakthrough rates of 13 particle sizes vary: the interception effect of small to medium sized falling rocks with particle sizes ranging from 0.25 m to 2.25 m is effective, but the interception rate of passive protection net cannot reach 100%. When the particle size is larger than 2.25 m, the passive protection net fails, that is the upper limit of the design of the passive protection net under the Xiaotunyan collapse zone is the 2.25 m particle size of rockfall. According to the calculation, the failure probability of all rockfall particle sizes intercepted by the passive protection net is less than 5%, which is within the acceptable scope. Conclusion The research results provide a reference for rockfall protection measures in the Xiaotunyan collapse zone and are of great significance for the protection of life and property safety for people in karst mountainous areas.

To analyze the episodic alteration of Middle Permian carbonate reservoirs by complex hydrothermal fluid in southwestern Sichuan Basin, petrology, geochemistry, fluid inclusion and U-Pb dating researches are conducted. The fractures and vugs of Middle Permian Qixia–Maokou formations are filled with multi-stage medium−coarse saddle dolomites and associated hydrothermal minerals, which indicates that the early limestone/dolomite episodic alteration was caused by the large-scale, high-temperature, deep magnesium-rich brine along flowing channels such as basement faults or associated fractures under the tectonic compression and napping during the Indosinian. The time of magnesium-rich hydrothermal activity was from the Middle Triassic to the Late Triassic. The siliceous and calcite fillings were triggered by hydrothermal alteration in the Middle and Late Yanshanian Movement and Himalayan Movement. Hydrothermal dolomitization is controlled by fault, hydrothermal property, flowing channel and surrounding rock lithology, which occur as equilibrium effect of porosity and permeability. The thick massive grainstone/dolomites were mainly altered by modification such as hydrothermal dolomitization/recrystallization, brecciation and fracture-vugs filling. Early thin–medium packstones were mainly altered by dissolution and infilling of fracturing, bedding dolomitization, dissolution and associated mineral fillings. The dissolved vugs and fractures are the main reservoir space under hydrothermal conditions, and the connection of dissolved vugs and network fractures is favorable for forming high-quality dolomite reservoir. Hydrothermal dolomite reservoirs are developed within a range of 1 km near faults, with a thickness of 30–60 m. Hydrothermal dolomite reservoirs with local connected pore/vugs and fractures have exploration potential.

[Introduction] Speeding up the offshore wind power construction and development is of great significance to promoting the adjustment of China's energy structure. China is accelerating the process of its wind power development in the entire offshore area, and the geological survey is a vital foundation and key technology of offshore wind power development. [Method] By studying the marine geological survey technologies at home and abroad and combining years of experience in different sea areas, this paper proposed a new technology of engineering geological modeling for offshore wind power development based on the principle of consistency. Firstly, the survey equipment selection and survey line layout started from a three-dimensional initial model to evaluate the impact of geological changes and geohazards on the offshore wind power engineering construction and took into full account the ship selection, field in situ and laboratory tests, and correlation of geophysical prospecting and geotechnical data. Then, with abundant and continuous data obtained from the boreholes and the whole wind farm during the feasibility study and detailed survey, the methods of combination of indoor geotechnical tests with the in-situ tests, the combination of multiple geophysical prospecting devices and the combination of geotechnical and geophysical prospecting methods were used to conduct a consistency analysis of various data, manage the geological survey data platform, update the model and build the final model, and the engineering geological model was continuously optimized and iterated in the subsequent stages. The engineering geological model provided comprehensive engineering geological information for the entire life cycle of offshore wind farm design, installation, operation, maintenance and decommissioning. [Result] The research results and offshore wind power geological survey examples show that by conducting consistent comprehensive layout and data analysis, effectively connecting geotechnical investigation with engineering geophysical prospecting and constructing a three-dimensional crossing engineering geological model, it can effectively solve the problem of "ambiguities of geological survey data" and improve the reliability, accuracy and application of geological survey data. [Conclusion] The new method proposed is one of the effective methods to reduce cost and increase efficiency in offshore engineering as well as the embryonic form of digital twin of offshore wind power geological survey and the foundation for the construction of a geological survey big data base.

Based on the comprehensive analysis of core, thin section, logging and seismic data, this study carried out the identification and comparison of Permian Changxing Formation sequences, clarified the typical sedimentary architectures of intra-platform shoal, investigated the vertical and horizontal development and distribution of intra-platform shoal in each sequence, and thus established the sedimentary evolution model of shoal body. The study results are reflected in four aspects. First, there are two complete third-order sequences (SQ1 and SQ2) in Changxing Formation in central Sichuan Basin. SQ1 is generally thick in the north and thin in the south, and SQ2 shows a thickness differentiation trend of “two thicknesses and three thinnesses”. Second, the Changxing Formation in central Sichuan Basin mainly develops intra-platform shoal, inter-shoal sea and intra-platform depression subfacies. In the vertical direction, the intra-platform shoal mainly presents two typical sedimentary sequences: stable superposed and high-frequency interbedded. Third, the stable superimposed sedimentary sequence is developed in the shoal belt at the edge of intra-platform depression, which is composed of two shoal-forming periods and located in the highstand systems tracts (HSTs) of SQ1 and SQ2. The high-frequency interbedded sedimentary sequence is developed in the southern shoal belt of intra-platform depression, which is composed of four shoal-forming periods and mainly located in the HST of SQ2. Fourth, during the SQ1 deposition, the intra-platform shoal was mainly developed at the edge of the intra-platform depression on the north side of the study area, and the inter-shoal sea subfacies was mainly developed on the south side. During the SQ2 deposition, the intra-platform shoal was widely developed in the area, forming two nearly parallel intra-platform shoal belts. The study results provide direction and ideas for exploration of Changxing Formation intra-platform shoal reservoirs in central Sichuan Basin.

[Introduction] The current marine geological exploration, particularly the geotechnical investigation, often follows traditional experiences without a clear objective, and lacks the evaluations of soil sample disturbance and test results. Therefore, it is necessary to conduct in-depth research on marine geotechnical investigation technology. [Method] Based on the domestic and international research on marine geological exploration technology and multi-year working experience in different sea areas, we developed a new accurate marine geological exploration technology with emphasis on the principle of consistency. The geotechnical investigation part of the new method included two basic aspects: (1) comprehensive evaluation of soil sample disturbance; (2) comprehensive evaluation of consistency of soil strength test results. [Result] The three-dimensional cross-consistency analysis of geotechnical, geophysical, and geological models has established an accurate geological exploration system. Several examples of marine engineering projects showed that the new technology can screen good acquisition methods and data through comprehensive evaluation of clay soil sample disturbance, and conduct consistency analysis of various data by combining the laboratory geotechnical tests with in-situ tests and the routine geotechnical tests with advanced geotechnical tests to obtain richer and more continuous data at the borehole. Compared with the traditional single geotechnical test, our new technology demonstrated the improved reliability and accuracy of the data, and the missing data between the sampling points are compensated. [Conclusion] The proposed new method can reinforce the application of geological exploration data, reduce investigation costs, and provide more geotechnical parameters that are more reliable for marine engineering projects including offshore wind power.

Reliable evolution curve of tectonic-burial history is essential for the research of the source rock evolution, reservoir formation and hydrocarbon accumulation of target strata of basin. Previous publications reported the tectonic-burial evolution history curves established depending on regional geological setting, formation (denuded) thickness, and tectonic movements, which were uncertain due to the difference in such geological understandings. For the ancient marine carbonates in China, which have experienced multiple tectonic movement reformation, it is more difficult to reconstruct tectonic-burial evolution history. In this paper, based on the identification of carbonate cements and the establishment of diagenetic sequence, through coupling carbonate laser ablation U-Pb dating and clumped isotope (Δ47) thermometer, two understandings were proposed: (1) The tectonic-burial curves of the Sinian Dengying Formation in the Sichuan Basin were established under the constraints of absolute age and temperature, which avoided the problems of uncertainty of tectonic-burial history curves in previous studies; (2) The new tectonic-burial history curve provided critical reference for study on the source rock evolution, reservoir origin and hydrocarbon accumulation of the Sinian Dengying Formation of the Sichuan Basin, revealing three stages of hydrocarbon accumulation in the Dengying gas reservoir including Silurian, Permian and Yanshanian-Himalayan periods. The proposed method of reconstructing tectonic-burial evolution curve is not only suitable for the ancient marine carbonates which experienced multiple tectonic movement reformation, but is also promising for the study of source rock evolution, reservoir origin and hydrocarbon accumulation.

A new method for reconstructing the geological history of hydrocarbon accumulation is developed, which are constrained by U-Pb isotope age and clumped isotope (Δ47) temperature of host minerals of hydrocarbon-bearing inclusions. For constraining the time and depth of hydrocarbon accumulation by the laser in-situ U-Pb isotope age and clumped isotope temperature, there are two key steps: (1) Investigating feature, abundance and distribution patterns of liquid and gaseous hydrocarbon inclusions with optical microscopes. (2) Dating laser in-situ U-Pb isotope age and measuring clumped isotope temperature of the host minerals of hydrocarbon inclusions. These technologies have been applied for studying the stages of hydrocarbon accumulation in the Sinian Dengying gas reservoir in the paleo-uplift of the central Sichuan Basin. By dating the U-Pb isotope age and measuring the temperature of clumped isotope (Δ47) of the host minerals of hydrocarbon inclusions in dolomite, three stages of hydrocarbon accumulation were identified: (1) Late Silurian: the first stage of oil accumulation at (416±23) Ma. (2) Late Permian to Early Triassic: the second stage of oil accumulation between (248±27) Ma and (246.3±1.5) Ma. (3) Yanshan to Himalayan period: gas accumulation between (115±69) Ma and (41±10) Ma. The reconstructed hydrocarbon accumulation history of the Dengying gas reservoir in the paleo-uplift of the central Sichuan Basin is highly consistent with the tectonic-burial history, basin thermal history and hydrocarbon generation history, indicating that the new method is a reliable way for reconstructing the hydrocarbon accumulation history.

Ancient marine carbonates experienced complex modifications, making it difficult to identify reservoir genesis and effective porosity before hydrocarbon migration. To solve these issues, we used element mapping and carbonate mineral laser U-Pb radiometric dating techniques to study the diagenetic environments based on geochemistry and diagenesis-porosity evolution based on geochronology of the dolomite reservoir of the Sinian Qigebrak Formation, northwest Tarim Basin. Two major understandings were obtained as follows: (1) Supported by petrographic observations, the element mapping, stable isotopes, strontium isotope, and cathodoluminescence tests were performed on different phases of dolomite cements precipitated in vugs and dissolved fissures. The results show that the dolomite reservoirs of the Qigebrak Formation went through freshwater, marine, extremely shallow burial, burial and hydrothermal diagenetic environments after synsedimentary dolomitization; the reservoir spaces were mainly formed in the synsedimentary period (primary pores) and freshwater environment (supergene dissolution pores) before burial; whereas the marine, burial and hydrothermal environments caused the gradual filling of reservoir space by dolomite cements. (2) Based on the above understandings, each phase of dolomite cement precipitated in the reservoir space was dated by the U-Pb radiometric dating technique, and the diagenesis-porosity evolution curves constrained by geochronology were established. The loss of reservoir porosity mainly occurred in the early Caledonian, and during the peak period of hydrocarbon generation of Yuertusi Formation source rock, the reservoirs still maintained at a porosity of 6%–10%. The above understandings provide a certain basis for the evaluation of accumulation effectiveness of the Sinian Qigebrak Formation, northwestern Tarim Basin, and provide a case for the application of mapping and dating techniques in the study of ancient carbonate reservoirs.

Abstract: Weiyuan shale gas play is characterized by thin high-quality reservoir thickness, big horizontal stress difference, and big productivity differences between wells. Based on integrated evaluation of shale gas reservoir geology and well logging interpretation of more than 20 appraisal wells, a correlation was built between the single well test production rate and the high-quality reservoir length drilled in the horizontal wells, high-quality reservoir thickness and the stimulation treatment parameters in over 100 horizontal wells, the dominating factors on horizontal well productivity were found out, and optimized development strategies were proposed. The results show that the deployed reserves of high-quality reservoir are the dominating factors on horizontal well productivity. In other words, the shale gas well productivity is controlled by the thickness of the high-quality reservoir, the high-quality reservoir drilling length and the effectiveness of stimulation. Based on the above understanding, the development strategies in Weiyuan shale gas play are optimized as follows: (1) The target of horizontal wells is located in the middle and lower parts of Longyi 11 (Wei202 area) and Longyi 11 (Wei204 area). (2) Producing wells are drilled in priority in the surrounding areas of Weiyuan county with thick high-quality reservoir. (3) A medium to high intensity stimulation is adopted. After the implementation of these strategies, both the production rate and the estimated ultimate recovery (EUR) of individual shale gas wells have increased substantially.

The Upper Ordovician Wufeng-Lower Silurian Longmaxi shale is the only yield layer of commercial deve-lopment of shale gas in China at present. However, there are significant differences in the production of individual shale gas wells in different areas of the Sichuan Basin and its periphery. This paper investigates those differences from the perspective of reservoir space. The pore development of 36 shale samples from the Lower Rhuddanian in 5 typical wells with different reservoir pressure in different tectonic areas in the Sichuan Basin was compared by applying, petromi-neralogical, structural geological and reservoir geological methods. The reservoir space in these shales is dominated by organic pores. With the increase of TOC content, the volumes of micropores (< 10 nm), mesopores (10~50 nm), macropores (>50 nm) and total pores in different structural regions show different trends, reflecting different stages of pore evolution. A preliminary organic pore development model of shale has been established. The extent of pore development in shale samples located in the overpressure area in the basin is obviously better than that in the structural transformation area of the basin margin. It is confirmed by experiments that the shale pores may be compacted under high pressure conditions, and the degree of compaction is closely related to the organic matter pore size, the rock mineral composition, the organic matter content, the domain structure conditions and the pressure coefficient. The areas affected by the weak tectonic movement and having a high pressure coefficient are favorable areas for pore development.

Through the development and calibration of a reference material which is 209.8 Ma old using a newly-developed Laser Ablation (LA) Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS) technique, we successfully overcome the difficulty in sampling and dating ultra-low U-Pb ancient marine carbonates, which was previously untenable by isotope dilution (ID) methods. We developed the LA-MC-ICP-MS in situ U-Pb dating technique for ancient marine carbonates for the study of diagenesis-porosity evolution history in Sinian Dengying Formation, Sichuan Basin. By systematically dating of dolomitic cements from vugs, matrix pores and fractures, we found that the burial and diagenetic process of dolomite reservoirs in Sinian Dengying Formation was characterized by progressive filling-up of primary pores and epigenic dissolution vugs. The filling of vugs happened in three stages, early Caledonian, late Hercynian-Indosinian and Yanshanian-Himalayan, while the filling of matrix pores mainly took place in early Caledonian. The unfilled residual vugs, pores and fractures constitute the main reservoir sapce. Based on the above knowledge, we established the diagenesis-porosity evolution history of the dolomite reservoir in Sinian Dengying Formation, Sichuan Basin. These findings are highly consistent with the tectonic-burial and basin thermal histories of the study area. Our study confirmed the reliability of this in situ U-Pb dating technique, which provides an effective way for the investigation of diagenesis-porosity evolution history and evaluation of porosity in ancient marine carbonate reservoirs before hydrocarbon migration. Key words: laser ablation, in-situ U-Pb dating, Sichuan Basin, Sinian Dengying Formation, diagenesis-porosity evolution, carbonates

Objective To identify the novel radioresistance-associated genes in esophageal squamous cell carcinoma and build a foundation for the individualized radiotherapy. Methods Two groups of ESCC patients were selected: radiosensitive group (S) and radioresistant group (R). Copy number variation(CNV) profiles of the selected ESCC tissues were screened using genechip microarray to obtain significant symbolic genes. Furthermore, qPCR analysis was used to confirm the results of the microarray. Results Microarray assay results showed that the significant differences of CNVs occurred in chromosomes 3, 4, 8, 11 and 17, respectively. The symbolic genes were ROBO1 (CN Loss), NSD2 (CN Loss), CSMD3 (CN Gain), CADM1 (CN Loss) and NF1(LOH). Further, qPCR results demonstrated the radioresistant genes were NSD2 and CADM1 which were related to DNA damage repair and cell adhesion, respectively. Conclusion The application of genechip microarray technique in CNV profiles screening is a powerful strategy to identify novel radioresistance-associated biomarkers of ESCC. NSD2 and CADM1 may be the radioresistance-associated candidate genes in ESCC.

In order to understand the seasonal variations in the spatial distribution of the mass concentration and grain size of the suspended particulate matter (9PM) of the Poyang Lake, we acquired MODI9 satellite image data and made on-site surveys by using the laser in-situ scattering and transmissometry (LIS9T-100) and filtration device in three cruises in the Poyang lake in October (the dry season) 2008, 2009 and July (the wet season) 2011 respectively. The result showed that; 1) the mass concentration of the SPM was high in the north and middle parts, while low in the south part of the lake; 2) the concentration of the SPM in the vertical direction was increasing from surface to bottom in general, while due to the wind flow and sand mining activities, there were no obvious distribution pattern in some areas of the middle and south parts of the lake; 3) the average mass concentration of the SPM was higher in dry seasons than in wet seasons, and the spatial differences were smaller in dry seasons than in wet seasons; 4) the SPM was mainly composed of silt sand and fine silt sand, with the proportion of the fine silt sand being the highest; 5) the grain size of SPM ranged from 8 µm ~ 90 µm, and the distribution pattern of the grain size was uniform in the dry and wet seasons, while the mid-value in dry seasons was smaller; 6) the grain size of the SPM was smaller in the north and larger in the south; 7) the frequency spectrum of the grain size shaped double-peaked and three-peaked forms, and with the same form in the north part while different forms in the south part of the lake in different seasons; 8) all of the variations in the distribution of the mass concentration and grain size were affected and determined by the hydrodynamics, sediment erosion, wind flow, sand mining and biological activities of the lake. [ABSTRACT FROM AUTHOR]

We calculates the temperature vegetation dryness index (TVDI) by using Normalized Difference Vegetation Index (NDVI) derived from the HJ-1A/1B CCD and Land Surface Temperature (LST) derived from the HJ-1B IRS form March to June, 2011. The TVDI of the surface soil moisture products of AMSR-E was tested by using the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) collected simultaneously. The results show that there is a significant negative correlation (with a correlation coefficient of -0.697) between TVDI and AMSR-E, indicating that the TVDI calculated based on the HJ-1A/1B can effectively reflect the containing water of Poyang Lake Watershed. The analysis on the spatial distribution of drought in 2011 by using TVDI-measured results shows that the most severely affected areas were the region around the Poyang Lake and Xiushui River basin, the Poyang Lake basin is dominated by moderate drought in late March, the drought of the South becomes more serious in late April, in May, almost 80% of the areas in Poyang Lake basin areas are subject to the impact of drought of different degrees. [ABSTRACT FROM AUTHOR]

According to the principle of energy conversion, a novel model used for energy conversion from low frequency linear micro-vibration kinetic energy to power was designed. Using the finite element method, the no-load induced electromotive force amplitude of the conversion model was optimized by changing the structure and size of the energy converter component. The final optimal sizes of the converter are Φ16 x 90 mm. Meanwhile, the performance of the model with optimal size was tested by virtual instrument technology. From the available experimental and simulation results, the system natural frequency is 11 Hz, and the maximum no-load inducted electromotive force is 2.4 V. [ABSTRACT FROM AUTHOR]

BACKGROUND: Carlin-type gold deposits have attracted much attention because of the influence of As on the analysis and recovery of gold. It is necessary to develop the specific reference materials (RM) to support application research.OBJECTIVE: Study samples were collected from the super large Carlin-type gold deposit in the Yangshan gold mine, discovered in recent years. Four kinds of reference materials GBW07854-GBW07857 for Carlin-type gold ore were developed according to country-level standard technical specification.METHODS: A total of 20 laboratories simultaneously determined element values. The main gold analysis methods included Atomic Absorption Spectrometry and Fire Assay. Wet analysis uses gradient roasting-activated carbon adsorption of gold to separate arsenic and other interference components. Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) and Spectrophotometry were mainly used to analyze arsenic. Citation analysis relative deviation permissible limit to define within-group outliers makes up for the incompleteness of the Dixon and Grubbs methods to eliminate outliers.RESULTS: The homogeneity test index F < F0.05(29, 30)=1.84, indicated that there were no significant differences between the groups and within the group. No statistically significant changes were observed in 5 analyses during 22 months. The certified values of gold and arsenic in this series of certified reference materials (CRMs) were superior to those of the same level country-level gold ore RM and foreign arsenic-bearing polymetallic ore RM.CONCLUSIONS: This series of CRMs can be used as standards for the analysis and study of gold and arsenic in Carlin-type gold deposits.

Biomarkers are applied worldwide in marine environmental assessment due to their "early warning-function to chemical pollutants. Several integrative index approaches such as multi-marker pollution index (MPI), integrated biomarker response (IBR), bioeffect assessment index (BAI), biomarker response index (BRI), and health assessment index (HIS), have been developed based on biomarkers. By transforming the complex alterations of biomarkers into a single class or value, these approaches have been so far the useful tools for assessing the environmental quality. This review summarized the establishment of evaluation indicator system, the calculation of integrative index, the grading of pollution status, and the practical applications of each approach, and discussed the existing problems in marine environmental assessment based on biomarker index. Some improving suggestions were also proposed. [ABSTRACT FROM AUTHOR]

The shale gas enrichment pattern of Well Wuxi-2 in northeast Chongqing was studied, based on the data of the drilling, graptolite biostratigraphy, geochemistry, rock minerals, microscopic characteristics of reservoir beds and tectonic conditions, etc. The organic-rich shale of Upper Ordovician Wufeng Formation—Lower Silurian Lungmachi Formation is 89.8 m thick in Well WX-2. The graptolite biozonations are completely developed in this well, and the organic-rich shale intervals extend upward from the late Katian of the Ordovician to the early Telychian of the Lower Silurian. The deposition time of the organic-rich shale is far longer and the thickness is larger than those in other areas of the Sichuan Basin. The highest measured gas content exceeded 8 m3/t in Well WX-2, and the gas content is mainly controlled by TOC. The organic nano-pores are the main storage space, and the minerals contribute less to the storage space. The organic pores larger than 50 nm are well-developed and those less than 10 nm are the main reservoir space of adsorbed gas. The target intervals of Well WX-2 are located under the neutral surface of compressional Tianba anticline. Two vertical fracture (cleavage) development zones, which are beneficial for shale gas storage and complex fracture network formation during later fracturing, were formed in brittle layers of this organic-rich shale. Compressional faults existed in two limbs of the Tianba anticline, with non-permeable shale developing on both sides of fault planes and development of clay smear, which shows that the faults have good sealing properties, and are favorable for shale gas preservation. Thus the good match between the above various accumulation conditions forms the “tectonic sweet-spot” of shale gas in this study area. Key words: Well WX-2, shale gas, graptolite biostratigraphy, organic pore, tectonic sweet-spot, enrichment pattern

This paper mainly discusses the industrialization progress, “sweet spot” evaluation criterion, E&P technologies, success experiences, challenges and prospects of China's shale gas. Based on the geologic and engineering parameters of the Fuling, Changning and Weiyuan shale gas fields in the Sichuan Basin, this paper points out that China's shale gas has its particularity. The discoveries of super-giant marine shale gas fields with high evolution degree (Ro=2.0%−3.5%) and ultrahigh pressure (pressure coefficient=1.3−2.1) in southern China is of important scientific significance and practical value to ancient marine shale gas exploration and development to China and even the world. It's proposed that shale gas “sweet spots” must be characterized by high gas content, excellent frackability and good economy etc. The key indicators to determine the shale gas enrichment interval and trajectory of horizontal wells include “four highs”, that is high TOC (>3.0%), high porosity (>3.0%), high gas content (>3.0 m3/t) and high formation pressure (pressure coefficient>1.3), and “two well-developed” (well-developed beddings and well-developed micro-fractures). It's suggested that horizontal well laneway be designed in the middle of high pressure compartment between the Upper Ordovician Wufeng Formation and Lower Silurian Longmaxi Formation. The mode of forming “artificial shale gas reservoir” by “fracturing micro-reservoir group” is proposed and the mechanisms of “closing-in after fracturing, limiting production through pressure control” are revealed. Several key technologies (such as three-dimensional seismic survey and micro-seismic monitoring of fracturing, horizontal wells, “factory-like” or industrialized production mode, etc.) were formed. Some successful experiences (such as “sweet spot” selection, horizontal well laneway control, horizontal length optimization and “factory-like” production mode, etc.) were obtained. The four main challenges to realize large-scale production of shale gas in China include uncertainty of shale gas resources, breakthroughs in key technologies and equipment of shale gas exploration and development below 3 500 m, lower cost of production, as well as water resources and environment protection. It is predicted that the recoverable resources of the Lower Paleozoic marine shale gas in southern China are approximately 8.8×1012 m3, among which the recoverable resources in the Sichuan Basin are 4.5×1012 m3 in the favorable area of 4.0×104 km2. The productivity of (200−300)×108 m3/a is predicted to be realized by 2020 when the integrated revolution of “theory, technology, production and cost” is realized in Chinese shale gas exploration and development. It is expected in the future to be built “Southwest Daqing Oilfield (Gas Daqing)” in Sichuan Basin with conventional and unconventional natural gas production. Key words: shale gas field, economic sweet spot, micro gas reservoir, horizontal well, factory-like production, volume fracturing, development cost, resource potential, favorable target

The main factors controlling the enrichment and high yield of shale gas were analyzed based on the recent research progress of depositional model and reservoir characterization of organic-rich shale in China. The study determines the space-time comparison basis of graptolite sequence in the Upper Ordovician Wufeng Formation–Lower Silurian Longmaxi Formation and proposes the important depositional pattern of marine organic-rich shale: stable ocean basin with low subsidence rate, high sea level, semi-enclosed water body, and low sedimentation rate. Deposited in the stage of Late Ordovician-Early Silurian, the superior shale with thickness of 20−80 m and total organic carbon (TOC) content of 2.0%−8.4% was developed in large deep-water shelf environment which is favorable for black shale development. Based on the comparison among the Jiaoshiba, Changning and Weiyuan shale gas fields, it is believed that reservoirs of scale are mainly controlled by shale rich in biogenic silica and calcium, moderate thermal maturity, high matrix porosity, and abundant fracture. The shales in the Wufeng and Longmaxi formations are characterized by porosity of 3.0%−8.4%, permeability of 0.000 2×10−3−0.500 0×10−3 μm2, stable areal distribution of matrix pore volume and their constituents, great variation in fracture and pore characteristics among different tectonic regions as well as different well fields and different intervals in the same tectonic. The Cambrian Qiongzhusi shale features poor physical properties with the porosity of 1.5%−2.9% and the permeability of 0.001×10−3−0.010×10−3 μm2, resulted from the carbonization of organic matter, high crystallinity of clay minerals and later filling in bioclastic intragranular pores. Four factors controlling the accumulation and high production of shale gas were confirmed: depositional environment, thermal evolution, pore and fracture development, and tectonic preservation condition; two special features were found: high thermal maturity (Ro of 2.0%−3.5%) and overpressure of reservoir (pressure coefficient of 1.3−2.1); and two enrichment modes were summarized: “structural sweet spots” and “continuous sweet area”. Key words: shale gas, organic-rich shale, sedimentary model, reservoir characterization, sweet spot area, Jiaoshiba shale gas field, Changning shale gas field, Weiyuan shale gas field

The article presents a study which examines the trends of physical education classroom teaching based on the analysis of the 5th Session of Demonstration and Observation of Physical Education Teaching in Elementary and Middle Schools in China. It notes that the study found that physical education classroom teaching had changed and objectives were set more accurately and expressed in a clear way. Furthermore, the study determined that classroom teaching strategies were more diversified.

Background Klotho is closely related to the occurrence and development of kidney disease. Salt-sensitive hypertension (SSH) is often accompanied by kidney disease. At present, there are few reports on the role and molecules mechanism of klotho in renal injury in SSH. Objective To investigate the role and molecules mechanism of klotho in renal injury in SSH. Methods The rat glomerular mesangial cell line HBZY1 was selected as the experimental cells from June 2021 to January 2022, and the experimental cells were divided into the control group and the model group. The model of HBZY1 cell injury induced by NaCl 137 mmol/L and angiotensin Ⅱ (Ang Ⅱ) 10-6 mmol/L was used to simulate the renal injury in SSH, and the cells were collected. The differences in the expression of klotho mRNA and protein were detected by real-time fluorescent quantitative PCR (qRT-PCR) and Western Blot. The interference vector and overexpression vector of klotho and the overexpression vector of angiotensin Ⅱ type 1 receptor (AT1R) were constructed. The klotho interference experiments were divided into five groups, including the control group, empty group, klotho-siRNA1 group, klotho-siRNA2 group and klotho-siRNA3 group; the klotho overexpression experiments were divided into three groups, including the control group, empty group and klotho overexpression group; the AT1R overexpression experiments were divided into three groups, including the control group, empty group and AT1R overexpression group. The constructed vectors were transfected into cells with verified transfection efficiency. After successful transfection, the experiment was divided into two parts. The first part of the experiment was to verify the renal protective effect of klotho, the experiment subjects were divided into four groups, including the control group, model group, klotho overexpression group and klotho interference group. The second part of the experiment was to explore whether the renal protective effect of klotho was related to AT1R, the experiment subjects were divided into three groups, including the model group, klotho overexpression group and klotho+AT1R overexpression group. After successful transfection, the tests including cell viability detected by cell counting kit-8 (CCK-8) method, reactive oxygen species (ROS) content detected by flow cytometry, malondialdehyde (MDA) and superoxide dismutase (SOD) content in cell supernatant detected by enzyme-linked immunosorbent assay (ELISA) , interaction effect between kltho and AT1R detected by co-immunoprecipitation (Co-IP) . Results Compared with the control group, mRNA level and protein expression of klotho in the model group decreased in model group (t=7.102, 7.506; P=0.002, 0.002) , klotho-siRNA2 interference effect was more significant (P

Background Hypertension is closely related to serum uric acid (SUA) level, and often accompanied by thyroid function changes. However, there are few reports on the relationship between thyroid hormone level and hyperuricemia (HUA) in euthyroid hypertensive patients. Objective To explore the correlation between serum thyroid hormone level and HUA in euthyroid individuals with essential hypertension (EH) . Methods Two hundred and sixty-seven euthyroid patients with EH were retrospectively selected from Department of Cardiology, Xianyang Hospital of Yan'an University from January 2019 to December 2020, including 101 with HUA (combined HUA group) and 166 without HUA (non-HUA group) . The general demographic data and laboratory examination indices of the two groups were compared, including gender, age, body mass index (BMI) , systolic blood pressure (SBP) , diastolic blood pressure (DBP) , smoking history, drinking history, total cholesterol (TC) , triacylglycerol (TG) , high-density lipoprotein cholesterol (HDL-C) , low-density lipoprotein cholesterol (LDL-C) , serum creatinine (Scr) , SUA, thyroid-stimulating hormone (TSH) , free triiodothyronine (FT3) , and free thyroxine (FT4) . Multivariate Logistic regression analysis was used to explore factors associated with HUA. Pearson correlation was used to examine the correlation between thyroid hormone level and SUA level. Results There were significant intergroup differences in gender ratio, mean age, BMI, and DBP, as well as prevalence of smoking history and drinking history (P

Objective: This study aimed to compare the differences of volatile components in flower buds of Zingiber mioga after drying and freezing. Methods: Volatile components in flower buds of Z. mioga was determined by headspace solid phase microextraction Gas Chromatography-Mass Spectrometer（HS-SPME-GC-MS） after drying and freezing, and the relative content was calculated by peak area normalization method. Results: Drying and freezing treatment had a significant effect on the volatile components of Z. mioga flower bud. A total of 152 volatile components were identified in fresh, frozen and dried Z. mioga flower bud, containing a variety of volatile pharmacodynamic components, mainly olefins, including β-phellandrene, α-Hmulene and levorotatory-β-pinene, and their relative content was high. After drying and freezing, the amount of volatile components in Z. mioga flower bud decreased significantly. The relative content of olefins in fresh and frozen samples was higher, and the relative content of olefins and alcohols after drying was higher. After drying and freezing treatment, 25 volatile components were retained, and new volatile components appeared, giving the dried and frozen Z. mioga flower bud a unique flavor. Conclusion: Fresh, dried and frozen Z. mioga flower bud contains more physiologically active components. Compared with freezing treatment, drying treatment has a greater impact on the relative content and composition of volatile components in Z. mioga flower bud. In actual production, appropriate treatment conditions are selected according to the application purpose.

Aiming at the problems of detecting targets with Haar-like,such as excessive feature values,expensive computational cost,inability to describe the target texture features,and low recognition rate etc.,this paper proposes an adaptive threshold IHL (Improved Haar-like LBP) feature extraction algorithm based on the information of the origin of the sliding window.More speci-fically,the algorithm first constructs the IHL feature coding method fusing Haar-like features and LBP features.Then,for computing Haar-like local binary features,a Gaussian matrix is used to obtain an adaptive threshold that conforms to the pixel distribution law,and the pixel information of the central point is introduced to ensure the rationality of the extracted feature value.Finally,the cascade classifier trained by AdaBoost is built and experiments are conducted on the KITTI vehicle data set and the INRIA Person pedestrian data set.The proposed algorithm,with a recognition rate of more than 94%,is proven effective with recognizing 1 102 pedestrian targets in 65 s and 1 852 vehicle targets in 114.3 s,which can significantly speed up target recognition time and obviously improve the detection accuracy compared with state-of-the-art methods.

Soil microbial carbon (C), nitrogen (N), and phosphorus (P) nutrient requirements and metabolic limitations are closely related to the availability of environmental nutrients. However, it is unclear how manure and chemical fertilization shift nutrient limitations for microbes in terms of the soil enzymatic stoichiometry in an apple orchard. Therefore, based on the long-term experiment located in an apple orchard established in 2008, this study applied the theory and method of soil enzyme stoichiometry to systematically investigate the effects of the combined application of manure and chemical fertilizers on soil C, N, and P turnover-related enzyme activities ( β -1,4-glucosidase, BG; leucine aminopeptidase, NAG; β -1,4- N -acetylglucosaminidase, LAP; and acid or alkaline phosphatase, PHOS) and their stoichiometric characteristics and analyzed their relationships with environmental factors and microbial carbon use efficiency. The experiment was designed with four treatments, such as, no fertilization input as the control (CK), single application of chemical fertilizer (NPK), combined application of manure and chemical fertilizer (MNPK), and single application of manure (M). The results revealed that:① at different growth stages of fruit trees, the soil microbial biomass C (microC) content of manure fertilizer treatments (MNPK and M) was significantly higher than that of no manure fertilizer treatments (CK and NPK). The content of microbial biomass N (microN) in the NPK, MNPK, and M treatments increased by 89%, 269%, and 213%, respectively, compared with that in CK ( P <0.05). ② Compared with those in the fertilization treatments, CK had higher leaf N and P contents (29.8 g·kg -1 and 2.17 g·kg -1 ) at the germination stage, and the leaf P content at the germination stage alone was significantly negatively correlated with soil available phosphorus (AP) content. ③ Soil enzyme stoichiometry analysis demonstrated that all data points in this study were above the 1:1 line, indicating that microbial communities had a strong phosphorus limitation. The range of vector length and angle was 0.56-0.79 and 59.3°-67.7°, respectively, in the growth period of fruit trees, and the vector angle was >45° in this study, which also reflected the strong phosphorus limitation of microorganisms. ④ RDA and random forest model analysis showed that organic carbon and available nitrogen (AN) were the main physical and chemical factors affecting vector length; AP, AN, and soil water content were the main physical and chemical factors affecting vector angle. Combined with SEM analysis, AN and dissolved organic carbon (DOC) directly affected microC and microN, AP directly affected microP and microN, DOC and AP directly affected vector length, and AP and microN directly affected vector angle. In addition, microbial carbon utilization was positively correlated with vector length and negatively correlated with vector angle. In summary, the combined application of manure and chemical fertilizers regulated microbial carbon and phosphorus metabolism by affecting soil carbon and phosphorus content at different growth stages of fruit trees, thereby affecting microbial carbon utilization. This study provides a scientific basis for manure and chemical fertilizers to improve soil quality and maintain soil health.

This article is to explore the antidepressant mechanism of Shugan Lipi recipe in regulating tryptophan metabolism,and to find out their common pharmacodynamic substances. UPLC-Q-TOF-MS technology was used to establish fingerprints of Shugan Lipi recipe,and 124 components were identified. The depressed mouse model was replicated by triple-one multiple stress method. Chaihu Shugan Powder,Sini Powder and Xiaoyao Powder were administered in groups to observe the changes in body weight and behavior of the mice. The results showed that compared with the model group,the body weight,sucrose preference percentage and autonomous activity behavior of each administration group were improved. Among them,the effect of Chaihu Shugan Powder was better than that of Sini Powder and Xiaoyao Powder. LC-MS/MS method was used to determine the contents of 5-hydroxytryptamine( 5-HT),kynurenine( KYN) and tryptophan( TPP) in blood,liver,brain,colon and other tissues,as well as TDO enzyme activity in liver. Western blot and RT-PCR were used to detect the protein and gene expression of TDO enzyme,respectively. It was found that the three prescriptions increased the ratio of 5-HT/KYN in different degrees,decreased the ratio of KYN/TRP in liver,colon and brain,and decreased the expression level and activity of TDO enzyme in liver. The order of their ability to regulate tryptophan metabolism was Chaihu Shugan Powder&gt;Sini Powder&gt;Xiaoyao Powder. In addition,the correlation between the chromatographic peaks in the fingerprints of Shugan Lipi recipes and the pharmacodynamic indexes of tryptophan metabolism was analyzed by the grey relation analysis. The grey relation analysis found that the chemical components with the highest correlation with tryptophan metabolism were mainly from Paeoniae Radix Alba,Citri Reticulatae Pericarpium,Aurantii Fructus Immaturus and Aurantii Fructus. UPLC-Q-TOF-MS was used to analyze the migration components in the plasma of mice after administration of Shugan Lipi recipe,and to verify the common pharmacodynamic substances of Shugan Lipi recipe. The migration of these detected components in plasma was studied,and a total of 18 prototype components and 36 metabolites were identified. Therefore,it was believed that Chaihu Shugan Powder,Sini Powder and Xiaoyao Powder could play an antidepressant role by reducing the expression of TDO enzyme in the liver and regulating the metabolism of tryptophan.The components contained in Paeoniae Radix Alba,Citri Reticulatae Pericarpium,Aurantii Fructus Immaturus and Aurantii Fructus were the common pharmacodynamic substances of Shugan Lipi recipe,which played an important role in regulating tryptophan metabolism.

Objective: To investigate the correlation of the single nucleotide polymorphisms (SNP) rs1126772, rs117291487, rs11730582, rs142608941 and rs6813526 of the osteopontin (OPN) gene with the risk of asthenozoospermia (AZS)., Methods: We included 135 AZS patients in the AZS group and another 239 fertile men as normal controls. Using the SNaPshot technique, we genotyped the rs1126772, rs117291487, rs11730582, rs142608941 and rs6813526 polymorphisms of the OPN gene in all the subjects and analyzed the correlation of the five SNPs with AZS., Results: The GA genotype and A allele of the OPN gene rs1126772 were found to be correlated with the risk of AZS (GA vs AA: OR = 0.55, 95% CI: 0.35－0.86, P = 0.009; A vs G: OR = 0.64, 95% CI: 0.46－0.89, P = 0.007), and so was the CT genotype and T allele at the RS11730582 locus (CT vs TT: OR = 0.526, 95% CI: 0.34－0.82, P = 0.009; T vs C: OR = 0.60, 95% CI: 0.44－0.83, P = 0.002). Haplotype analysis showed that the AATCT haplotype decreased the risk of AZS (AATCT: OR = 0.61, 95% CI: 0.42－0.88, P = 0.008) ., Conclusions: The polymorphisms of the OPN gene RS1126772 and RS11730582 may reduce the risk of AZS.

The combined application of amendments, such as hydroxyhistidine and zeolite, can effectively reduce both the bioavailability of heavy metals in soil and the bioaccumulation of heavy metals by rice, thus improving the safety of agricultural products. In this work, the effect of calcium magnesium phosphorus fertilizer on the content of available Cd in paddy soil and Cd accumulation in various parts of rice by lime combined with sepiolite was studied using a plot experiment. The results show that calcium magnesium phosphorus fertilizer can significantly promote the remediation effect of lime combined with sepiolite. Compared with the treatment with lime combined with sepiolite, the application of calcium magnesium phosphorus fertilizer significantly decreases the available Cd content in the soil and the Cd accumulation in the brown rice. With calcium magnesium phosphorus fertilizer of 2250 kg·hm -2 , Cd 2+ in soil formed less soluble cadmium phosphate, the content of extractable, reducible and oxidizable Cd was reduced, and the percentage of available Cd content in the soil was significantly ( P <0.05) reduced by 46.97%. Meanwhile, the Cd content in brown rice was decreased to 0.04 mg·kg -1 , which is far lower than the level required by the National Standard for Food Safety (GB 2762-2017) (0.2 mg·kg -1 ). In addition, the production of brown rice was increased by 28.34%. Correlation analysis shows that the Cd content in rice roots, straw, and brown rice was positively correlated with the available Cd content in soil ( P <0.01), and between the Cd content in brown rice and in roots and straw ( P <0.01). In general, the results indicate that the available Cd content in soil was the key factor affecting the Cd content in brown rice. The application of calcium magnesium phosphorus fertilizer can improve the amendment of lime combined with sepiolite for available Cd in soil and reduce the Cd absorption of rice roots and straw so that the Cd content in brown rice is reduced. The results show that the application of calcium magnesium phosphorus fertilizer enhances the effect of reducing the Cd content in brown rice by lime combined with sepiolite. Finally, it can both meet the safety requirements of brown rice quality and increase the yield of brown rice in Cd-contaminated paddy soil.

Soil microorganisms would reproduce rapidly and migrate directionally under the applied electric field. In this study, tetradecane-degrading bacteria were added at different locations in soil, and 1 V·cm -1 unidirectional DC electric field was applied to investigate the migration, distribution, and degradation characteristics of target bacteria in soil. The results showed that microorga-nisms migrated to the cathode and anode by electrodialysis and electrophoresis, respectively. The number of microorganisms migrated by electrodialysis was 3.5 times of that by electrophoresis. The application of electric field could make the soil environment spatially heterogeneous to affect the growth of microorganisms. The average number of soil microorganisms under electric field was 1.16×10 8 CFU·g -1 (6 days), which was 2.3 times of that without electric field. S 2 to S 4 were the efficient growth areas of microorganisms, with the average number after 30-day electric treatment being 2.8-3.5 times of that on the anode and cathode, and 2.1 times of that in the control. There was a significant positive correlation between the tetradecane degradation rate and the number of microorganisms (r=0.895, P＜0.05). The optimal tetradecane degradation region was near the cathode (S 4 ), where its degradation rate reached 94.6%. Based on these results, a model modified by environmental factors was established to simulate the spatial distribution of microorganisms under the combined effect of electrokinetic stimulation and transportation. According to the model, the number distribution of microorganisms could be deduced when exogenous bacteria were added in a fixed section. The results provide a theoretical basis for the efficient import of exogenous functional bacteria in electrokinetic-bioremediation of organic contaminated soil.

A series of MgAl hydrotalcite-derived composite oxides were prepared by co-precipitation methods. The effects of calcination temperature, reaction temperature, water vapor volume fraction, and alkali metal addition on the hydrolysis activity of the samples were investigated. The crystal structure, specific surface area, pore structure, and basic position distribution of the composite oxides were characterized using XRD, BET, TPD, and XPS. The results shown that the catalytic activity firstly increased and then decreased with the rise of calcination temperature. Furthermore, the sample that calcined at 650℃ can achieve the best catalytic activity (complete removal of COS lasted for 180 min). Increasing the reaction temperature improved the catalytic activity, which can present excellent catalytic activity and stability at temperatures above 70℃. In addition, the doping of the alkali metal Cs improved the catalytic activity, the complete removal time for COS can be maintained for 480 min.

In order to promote the application of anaerobic ammonium oxidation (ANAMMOX) to treat municipal wastewater, nitrosation was coupled with ANAMMOX and an ABR decarbonization system at the front of it; then used to build a system in which ABR decarbonization-nitrosation coupled with ANAMMOX was used to treat municipal wastewater. The high throughput sequencing technology of MiSeq was employed to analyze the structure of the microbial community in the sludge. Results showed that the average effluent COD concentration of the carbon removal system was 120 mg·L -1 and that the subsequent nitrosation system and ANAMMOX system would not be adversely affected by the effluent COD. Controlled by matching the nitrosation effluent with that from the ABR carbon removal system 2:1, the ANAMMOX influent, kept the ratio of the NO 2 - -N and NH 4 + -N matrix to ANAMMOX at about 1:1. The total nitrogen removal rate of the integrated reactor was 86%-92% and the COD of the effluent was 20-40 mg·L -1 . After the experiment, the number of bacteria in class γ -Proteobacteria in the nitrosation system, which are closely related to denitrification, increased. Members of class Sphingobacteria, which have the function of enhancing the growth rate of microorganisms and enhancing the rate of denitrification, were significantly increased in the ANAMMOX system. The nitrogen and carbon in the municipal wastewater could be stably and efficiently removed by the ABR Decarbonization-Nitrosation coupled with ANAMMOX process.

Controlling agricultural greenhouse gas emissions, such as N 2 O, is important in mitigating global climate warming. Through monitoring the dynamics of N 2 O emission fluxes, we investigated the effect of organic nitrogen (N) substitution of synthetic N on N 2 O emissions and the yield of winter wheat and summer maize in the Guanzhong Plain of Shaanxi Province, China. The study involved six treatments, consisting of no fertilizer (CK), synthetic N, phosphorus (P), and potassium (K) fertilizers alone (NPK), 75% NPK+25% organic N through manure (25%M), 50% NPK+50% organic N (50%M), 25% NPK+75% organic N (75%M), 100% organic N (100%M). The results showed that the peak value of the N 2 O emission flux appeared after fertilization, rainfall, and irrigation. In the wheat season, the emission flux of N 2 O varied from -1.33 to 144.2 μg·(m 2 ·h) -1 , with the highest peak value in the NPK treatment. In the maize season, the emission flux of N 2 O varied from 88.2 to 1800.1 μg·(m 2 ·h) -1 , and the 50%M treatment showed the highest peak value. The range in the total amount of N 2 O emissions from the different treatments in the wheat-maize rotation system was 429.8-2632.1 g·hm -2 , and the amount for the treatments decreased in order as follows:50%M > 25%M > NPK > 75%M > 100%M > CK. The yields of wheat, maize, or wheat plus maize were significantly higher in the fertilized treatments compared to the CK. Organic substitution treatments significantly increased wheat yield by 26.1% to 50.0% relative to the NPK treatment. While the maize yield in 50%M and 75%M treatments was similar to that in the NPK treatment, the 25%M and 100%M treatments showed significantly lower yields than with the NPK treatment. The total yield of wheat plus maize varied from 9166 to 17496 kg·hm -2 , of which total yield was significantly higher with 50%M and 75%M compared to NPK. Overall, the 75%M treatment is the best measure to guarantee crop yield and to reduce N 2 O emissions in the wheat-maize rotation system based on a one year study in the Guanzhong plain of Shaanxi Province.

The present work investigated the variations in the active characteristics of sludge during the operation period of an aeration membrane bioreactor, as well as their effects on the fouling of membrane module. Through discharging the excess sludge, the concentration of the mixed liquor was maintained at around 4 000 mg x L(-1) for 75 days, during which the characteristics of sludge were carefully tested every day to reflect its variation. Results indicated the dehydrogenase activity increased with the prolonging operation time. The increased activity of dehydrogenase had two effects on the operation of the bioreactor, one was the enhancement of pollutant removal by the microorganisms, while the other effect was the increase of extracellular polymeric substance (EPS), which led to a deteriorative effect on the membrane fouling. During the operation of the bioreactor, the sludge yield coefficient first increased, and then decreased to a certain degree with obvious decrease in particle size and increase in the amount of EPS, which also enhanced the quality of the effluent. At the same time, protozoon and metazoan were observed in the whole bioreactor at the late operational phase but relatively rare at the initial phase. Analysis of membrane fouling showed that the fouling rate of the membrane module increased during the late operational period, which was attributed to the deposition of fine sludge particles and EPS caused by the decreased particle size of the sludge and the increased amount of EPS.