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High-performance polymers have become a strategic material to ensure national security and national economic development owing to their excellent comprehensive properties. They have been widely applied in important fields such as aerospace, electronics, and medical devices. This study reviews the key varieties of high-performance polymers in four categories: highperformance resins and engineering plastics, organic fibers, bio-based resins and degradable materials, and special rubber and elastomers. The current status and characteristics of key high-performance polymers in China and abroad are analyzed. The study revealed that an industrialization system, including chemical raw material synthesis, modification, and product application, has been established in China. Besides, the current development challenges like the insufficient supply of key raw materials and limited development and application of products are discussed. Accordingly, relevant suggestion for technological innovation, key raw material security, and industrial innovation consortia construction are proposed, paving the way for the development of highperformance polymers in China.

Dihydroorotate dehydrogenase (DHODH) is a flavin-dependent metabolic enzyme that oxidizes dihydroorotate acid to orotic acid in the de novo synthesis pathway of pyrimidine metabolism. DHODH is located in mitochondria, closely related to cellular oxidative phosphorylation, and an important suppressor of the ferroptosis pathway. This study investigates the influence of DHODH on the progression of malignant tumors, including its important role in the de novo synthesis of pyrimidine, oxidative phosphorylation, and ferroptosis. The objective is to present evidence that DHODH is a potential target for the clinical treatment of tumors.

The performance of zirconium alloy cladding has always been a concern during reactor accidents. Ensuring the safe operation of high fuel consumption under reactivity initiated accident condition is also the core issue that scholars from various countries pay common attention to. The United States, France, Japan, Russia and other countries have carried out a large number of tests under reactivity initiated accident conditions. Some countries have also carried out the most advanced biaxial loading tests outside reactors, which has laid a solid foundation for these countries to occupy a leading position in the field of nuclear fuel safety. At present, there was no experimental study on pellet cladding mechanical interaction (PCMI) failure mode in Reactivity initiated accident (RIA) research in China. In order to establish our own safety criteria for reactivity initiated accident operating conditions, it is urgent to carry out domestic independent reactivity insertion accident test research, so as to provide data support for the commercial application of advanced fuel components. PCMI failure of cladding under reactivity insertion accident condition is a typical failure mode of high burnup fuel. Exploring effective test methods and obtaining test data to analyze the mechanism of pellet-cladding mechanical interaction is necessary. In this paper, out-pile simulated cladding failure was studied. Out-pile test device simulated PCMI was designed and domestic Zr-4 cladding was chosen as test material. High speed camera technology was used to assist. Hydrogen content absorbed in test material was used to simulate different high burnup cladding mechanical properties. The data of load, strain and fracture during the failure process of biaxial loading fuel element cladding were obtained. The macroscopic morphology and residual strain of test materials were analyzed after tests and stress state and maximum circumferential strain data of cladding tube under out-pile simulated reactivity insertion accident condition were obtained. The comparison with foreign research data verifies the feasibility and reliability of the PCMI failure test technology under out-pile simulated reactivity insertion accident condition. The results show that the circumferential strain of cladding tube decreases slightly with the increase of hydrogen content, and the damage degree of cladding is intensified. The circumferential strain of cladding tube increases obviously with the increase of temperature, and the lower limit of residual strain ratio tends to increase. The results of residual strain ratio are between -0.1 and 0.5, which accords with the range of residual strain ratio in reactor. The research results provide technical reserve and experience accumulation for future tests. It also provide reference data for the safety standards.

Objective To analyze the factors affecting the prognosis of soft tissue sarcomas originating from the mediastinum and lung using relevant data from the SEER database. Methods The data of 376 patients were collected from the SEER database, and were randomly divided into the train set (n=263) and validation set (n=113). The relationship between each variable and patient survival and prognosis was analyzed using the Kaplan-Meier method and Cox proportional risk regression to establish a nomogram, to predict the overall survival of patients. The calibration curves, consistency index, and ROC curves were used to evaluate the performance of the nomogram. Results Histological type, surgery, chemotherapy, tumor size, and tumor stage were the factors affecting the prognosis of primary mediastinal and pulmonary soft tissue sarcomas. The established nomogram could predict the 6-month, 1-year, and 2-year overall survival of patients, and the calibration curves showed good prediction accuracy with measured values. C index of the train set and validation set were 0.754 and 0.745, respectively. The areas under the curve of ROC were 0.849 and 0.924. Conclusion The nomogram established in this study can predict 6-month, 1-year, and 2-year overall survival in patients with primary mediastinal and pulmonary soft tissue sarcoma.

Objective To construct a new fusion luciferase-labeled Staphylococcus aureus (S. aureus) tracing system. Methods An S. aureus tracer strain was constructed by using DNA homologous recombination technique. The gene encoding fusion luciferase Antares2 was knocked in the genome of S. aureus strain USA300 by fusing with the enolase (Eno) encoding gene. The bioluminescence intensity was analyzed by mixing with the tracer strain and different substrates. The suitable tracer/substrate system was selected based on the detection of bioluminescence intensity. The sensitivity of the tracer/substrate system in vitro and in vivo was also evaluated. Results The knock-in plasmid pBT2-eno-antares2 was constructed. After transformed into S. aureus USA300, the Antares2 knock-in strain was screened out. The tracer strain USA300/Eno-Antares2 was identified by DNA sequencing as well as Western blot detection of Eno-Antares2 fusion proteins. Bacterial growth curve and hemolytic activity tests showed comparable results between USA300/Eno-Antares2 tracer strain and its wild-type USA300. USA300/Eno-Antares2 catalyzed substrates diphenylterazine (DTZ), furimazine (FUR), and hydrofurimazine (HFZ) to produce macroscopical bioluminescence. Analysis of different substrates at diverse concentrations revealed that USA300/Eno-Antares2/HFZ system exhibited the best performance. This system enabled reliable bioluminescence tracking of S. aureus with sensitivities of approximately 50 colony forming unit (CFU) in vitro and 100 CFU in vivo. Conclusion S. aureus USA300/Eno-Antares2/HFZ tracing system is a good tool, which can be used for the study of S. aureus infection, colonization, and dissemination.

According to the characteristics of underground electrical fire in coal mine, this paper analyzes the causes of underground electrical fire in coal mine, summarizes the research status of underground electrical fire intelligent monitoring and fire extinguishing technology in coal mine from the aspects of substation electrical monitoring system, electrical intelligent fire inspection, gas fire extinguishing system, water mist fire extinguishing system and new microcapsule fire extinguishing technology, and puts forward the research direction of underground electrical fire intelligent monitoring and fire extinguishing technology in coal mine in the future.

Coal spontaneous combustion disaster is one of the main disasters in the process of coal mining. The acquisition of multi-source three-dimensional parameters of spontaneous coal combustion, the in-depth analysis of data, the establishment of mathematical models and accurate prediction are the basic guarantee for the production of coal mining enterprises. This paper summarizes the basic status of research and application of coal spontaneous combustion monitoring and early warning from three aspects: monitoring methods, mathematical analysis and prediction methods of coal spontaneous combustion multi-source three-dimensional parameters, and further prospects the future development direction of coal spontaneous combustion intelligent monitoring and accurate prediction.

Background DSA is an irreplaceable diagnostic method for cerebral vascular disease. It is sensitive to intracranial macrovascular disease, but not to distal blood perfusion. In order to quantitatively assess the perfusion area of the feeding artery, this study is the first to propose an imaging method of the internal carotid artery (ICA) perfusion area relying on deconvolution algorithm and cross⁃correlation (CC) algorithm. Methods Four patients with cerebral vascular disease and 2 healthy subjects who underwent DSA examination in Luwan Branch of Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine from June 2020 to May 2021 were enrolled. The arterial input function (AIF) of the ICA was extracted, and a deconvolution algorithm was used to calculate the time to peak (Tmax) for each pixel. Then the CC algorithm was used to obtain the CC map related to the perfusion of the ICA at each pixel point of the whole brain. Area of interest (ROI) of AIF were randomly selected for 2 healthy subjects, calculated the root mean square error (RMSE) of the CC map for reliability analysis. The CC map was drawn for 4 patients with cerebral vascular disease for validity analysis. Results Reliability analysis showed that the RMSE values of Towne's and lateral views of the CC map and Tmax map of the left and right ICA in a healthy subject were 0.008±0.011, 0.022±0.002, 0.015±0.007, 0.004±0.008, and (0.108±0.181) s, (0.181±0.214) s, (0.301±0.230) s, (0.035±0.092) s; another healthy subject were 0.015±0.023, 0.007±0.011, 0.007±0.011, 0.005±0.012, and (0.172±0.275) s, (0.092±0.174) s, (0.087±0.156) s, (0.079±0.153) s. The averaged RMSE value of Tmax map was lower than the temporal resolution of DSA, indicating that the reliability of the CC map of the AIF value box in different ROIs of the ICA was high. Validity analysis showed that the CC map and Tmax map of the patient with acute ischemic stroke treated by intravenous thrombolysis bridging to mechanical thrombectomy can fully display the perfusion changes of the ICA after successful thrombectomy. Postoperative DSA in the patient with subacute ischemic stroke after endovascular therapy showed recanalization of the occluded artery, while the CC map showed no significant change in the perfusion of the ICA. The DSA of the patient with middle cerebral artery (MCA) stenosis without related ischemic events showed severe MCA stenosis, but the CC map showed that the ICA was well perfused, and no endovascular treatment was required. The DSA of the patient with acute ischemic stroke without MCA stenosis showed no MCA stenosis, but only sparse ICA⁃related perfusion was seen on the CC map. Conclusions The CC map and Tmax map based on DSA images have good reliability in different ROIs of AIF. The CC map can provide quantitative information on the perfusion area of the feeding arteries, which is helpful for accurate diagnosis and appropriate treatment decisions.

Based on the deformation theory, wear theory and similarity theory, the similarity relations of the various factors influencing the sand erosion phenomenon between in laboratory simulation working condition and in actual working condition were analyzed, and the similarity criterion of the wind sand test was proposed. In order to ensure a mutual conversion between the erosion damages of the engineering materials in the actual wind and sand environment and that in the laboratory simulation environment, this criterion restricted the numerical relations of the various parameters of the wind and sand environment between in actual and laboratory simulation working conditions. By adjusting the proportional relations of the sand - dust concentrations as well as the erosion speeds between in laboratory simulation and actual working conditions, the test speed was controlled and accelerated. Based on this criterion, the values of various parameters in the laboratory simulation wind and sand test could be designed, and the damage degree of engineering materials in the actual wind and sand environment in central and western Inner Mongolia could be predicted through the test mentioned above. The wind and sand test similarity criterion provided a theoretical basis and a basis for parameter selection for evaluating the erosion damage of engineering materials in a wind and sand environment by means of a simulation test.

Iridium is the most promising material for ultra - high temperature structure parts oxidation - resistant coatings in aerospace field due to its high melting point, strong corrosion resistance and low oxygen permeability under high temperature. The main factors affecting the service life of the iridium coating were the microstructure and oxidation characteristics at high temperature. There were two ways to improve high temperature oxidation resistance of the coating: one was improving preparation process to enhance density of iridium coating so as to reduce coating failure caused by grain boundary diffusion, the other was preparing ceramic coating or alloying to defend iridium coating from contacting with the oxidizing environments and extend its lifetime. Aiming at the problems in the applications of iridium coating, the research progress on modification of iridium coating was reviewed. The development direction of iridium coating modification technology was prospected.

Objective To determine the expression of S100A6 in liver tissues and investigate its role in the activation of hepatic stellate cells (HSCs). Methods Twelve C57BL/6 mice were randomly assigned to control group and liver fibrosis group. The mice in the latter group was administrated with carbon tetrachloride for 6 weeks to induce liver fibrosis. The liver tissue was harvested for Masson staining and S100A6 detection by immunohistochemistry. The expression of S100A6 at mRNA and protein levels was detected by RT-qPCR and Western blotting. After primary HSCs were isolated and cultured, their morphological changes in quiescence and activation were observed, and the mRNA and protein levels of S100A6 were detected after cultured for different time periods. Additionally, siRNA was utilized to interfere S100A6 expression in HSCs, and the mRNA and protein levels of S100A6, Collagen Ⅰ and α-SMA were tested by RT-qPCR and Western blotting. Results Masson staining displayed fibrosis in liver tissue in the mice of the liver fibrosis group, and S100A6 was also significantly expressed in the corresponding fibrous cord area of liver tissue in liver fibrosis group, and its mRNA and protein levels were obviously enhanced in the liver tissue when compared to the control group (P < 0.05). In vitro, HSCs auto-activated with the process of culture, and the mRNA and protein expression levels of S100A6 were gradually increased in a time depended manner in the HSCs (P < 0.05 or P < 0.001). Undoubtedly, the interference of S100A6 by siRNA efficiency dramatically inhibited the mRNA and protein expression of S100A6, Collagen Ⅰ, α-SMA (P < 0.05 or P < 0.001). Conclusion S100A6 is specifically expressed in hepatic fibrosis and activated HSCs, and is an important protein regulating the activation of HSCs. Thus, S100A6 might play important role in the pathogenesis of liver fibrosis.

BACKGROUND With the advancement of agricultural intensification and urbanization, pesticide residues in a large numbers of water environments in the world have exceeded the prescribed limit. The issue of pesticide pollution in the water environment has received extensive attention from all sectors of society. As the largest pesticide producer and user country in the world, the amount of pesticide residues in the water environment in China is much higher than other developed countries. Available studies have detected 19 pesticides in seven typical river basins in China (the Yangtze River, Taihu Lake, Yellow River, Songhua River, Heilongjiang, Grand Canal and Dongjiang), with an average concentration ranging from 0.02 to 332.75ng/L. Pesticides and their transformation products pose potential threats to the ecological environment and human health. Research on pesticide residues in the water environment is an indispensable part of water quality assessment. However, targeted screening is difficult to detect unknown pesticides and their transformation products. Therefore, the non-targeted screening of pesticide residues and their transformation products in the environment needs to be improved. OBJECTIVES To understand the pesticide pollution analysis techniques for environmental water samples. METHODS According to the analysis process of non-targeted screening of pesticide components, the targeted and non-targeted screening methods for pesticide residues in water quality samples in the past 5 years were reviewed, and the regulations and standards for pesticide residue limits and non-targeted screening of pesticides in water quality were summarized. The research progress of pesticide residue analysis methods in water environment in recent years was summarized. RESULTS The characteristics of liquid-liquid extraction (LLE), solid-phase extraction (SPE), solid-phase microextraction (SPME) and other pre-treatment methods were reviewed. Among them, solid-phase extraction was the main pre-treatment method for non-targeted pesticide screening and had good applications prospects. The development trend of analytical instruments from chromatography to chromatography mass spectrometry was discussed, and the production of a variety of high-resolution mass spectrometry provided multi-level analysis requirements for non-targeted pesticide screening. Finally, the guidelines, mass spectrometry database and various identification methods related to pesticide screening confirmation in recent years were summarized, and the development trend of pesticide pollution analysis technology in the water environment was prospected. CONCLUSIONS High resolution mass spectrometry technology poses a challenge to the sample pretreatment and purification process. The combination of multiple technologies in the water sample pretreatment process is the future development trend. Research on non-targeted pesticide screening based on high-resolution mass spectrometry is widely studied in the field of food testing although it has low priority in the environmental field. Relevant organizations at home and abroad have not yet issued relevant standards for screening and confirmation of unknown substances. Currently, the confirmation of unknown screening requires manual data analysis, which cannot be fully automated.

The test raw materials for this study are from a tin tailings in Yunnan. The tin grade in the tailings is 0.35%, which is the main valuable element. Cassiterite accounts for 72.39% of the total tin mineral, the yield of -0.02 mm are as high as 67.11%, and the tin occupation is 68.00%. It is difficult to recover by traditional flotation and shaking table processes. In view of the high content of fine particles in the tailings, the centrifugal gravity separation method is chosen for the process. With the centrifugal gravity separation process, a crude tin concentrate with a tin grade of 1.27% and an operating recovery of 70% can be obtained by one stage of rough separation; The tin concentrate with a tin grade of 4.11% and a recovery of 54.10% can be obtained by adopting the process of one roughing and two cleaning. The combined process of centrifugal gravity separation (one rougher and one cleaner) + shaking table (secondary cleaner) can obtain a tin concentrate with a tin grade of 17.57% and a recovery of 17.25%. The results show that the full centrifugal gravity separation process can be used to obtain tin concentrate with high recovery; In order to obtain high-grade tin concentrate products, the combined process of centrifugation and shaking table can be used. Finally, the appropriate process can be determined according to the actual needs, which realizes the further development and utilization of cassiterite in the tailings. [ABSTRACT FROM AUTHOR]

Ni-graphene composite coating was prepared on 45 steel substrates by electro-brush plating. The graphene layers,graphene in the composite coatings,the grain size and morphology of the coatings were characterized by transmission electron microscope(TEM),atomic force microscope(AFM),scanning electron microscope(SEM),energy dispersive spectrometer(EDS),Raman spectrometer,X-ray diffraction(XRD). The hardness of coatings was investigated by microhardness tester. The results show that graphene in Ni-graphene composite coating exists in the form of three(type Ⅰ,type Ⅱ,type Ⅲ),compared with the pure Ni coating,the grain size of Ni-graphene composite coatings reduces; when the content of graphene is 0.5g/L,the quality of Ni-graphene composite coating is best; because of the high hardness of graphene and its fine-grain strengthening effect,the hardness of Ni-graphene composite coating is 15.2% higher than that of pure Ni coating.

For problems of incomplete data collection and certain inaccurate data, the paper analyzed and discussed application status and prospect of data mining technologies such as association rule, classification, time series and series mining, clustering, space mining in power marketing system based on data characteristics of power marketing system.

The antibacterial hyperbranched polyurethane (HABPU) was obtained by grafting modification of self-made hyperbranched polyurethane (HCPU) with 1, 1-dimethylbiguanide hydrochloride (DBHC). A reverse osmosis membrane with bactericidal function was prepared by electrospinning technology. The surface morphology and properties of the reverse osmosis membrane were characterized by field emission scanning electron microscope (SEM), atomic force microscope (AFM), contact angle meter and solid surface Zeta potential analyzer. The performance of reverse osmosis membrane was characterized by porosity test, reverse osmosis membrane selective permeability test, anti-organic pollution test and antibacterial test. The results show that the surface morphology, roughness and porosity of HABPU modified membrane change less than those of unmodified membrane, and the wettability is enhanced. When pH value of electrolyte solution is 6~7, the surface of HABPU modified membrane is almost non-electrolytic. The permeation flux and rejection rate of the HABPU modified membrane reach (57.5±2.1) L/(m²⋅h) and (95.2±0.5)%, respectively, which are higher than those of the unmodified membrane. After contact with Escherichia coli and staphylococcus aureus for 2 h, the sterilization rate of HABPU modified membrane reach 100%, showing excellent antibacterial properties. [ABSTRACT FROM AUTHOR]

The copper content of a low-grade sulfur-oxygen mixed copper ore in Yunnan is 1.03%, which is the main valuable metal. Among them, copper sulfide accounts for 71.67%, copper oxide accounts for 28.33%, silicon dioxide and calcium oxide accounts for 43.26% and 12.66% respectively. Silicate and carbonate are the main gangue minerals. Through systematic experimental study, the asynchronous flotation-staged sulfurization process was determined, in which copper sulfide was selected first and then copper oxide was selected. Butyl xanthate was used as collector and lime as cleaning depressant in the flotation of copper sulfide, and butyl xanthate + ammonium dibutyl dithiophosphate was used as collector, sodium sulfide as vulcanizing agent and CMC as cleaning depressant in the flotation of copper oxide. In the two stages of roughing operation, depressant is not added to ensure copper recovery, while in the cleaning operation, depressant is added to improve copper grade. Finally, copper sulfide concentrate with copper grade of 18.95% and copper recovery of 66.27%, and copper oxide concentrate with copper grade of 20.11% and copper recovery of 19.87% can be obtained and the total copper recovery is 86.14%. [ABSTRACT FROM AUTHOR]

The wastewater from heating and chemical removal of a tungsten polymetallic sulfide ore in northern Guangdong was tested and analyzed, and it was found that returning directly to the original process had a greater impact on the recovery of copper, molybdenum and bismuth, so the wastewater was treated. Through systematic study, it is found that the residual medicament and suspended matter in the wastewater have an effect on the flotation. Through the way of coagulation, sedimentation and adsorption, with 25 mg/L XN-3 as flocculant, 20 mg/L PAC as coagulant aid, 20 g/L activated carbon as adsorbent, after sedimentation for 120 minutes, the removal effect of COD and SS is obvious. The removal rate of COD is 49.46%. Compared with the small-scale test, the modified backwater has little effect on the separation of copper, molybdenum and bismuth, except that the molybdenum grade of molybdenum concentrate has been reduced, and the zero discharge of wastewater from heating and removing reagents has been realized. [ABSTRACT FROM AUTHOR]

Aiming at the social welfare damage caused by the cost innovation of social capital in the operation stage, this paper constructs the ownership structure decision model with the purpose of the lowest comprehensive cost and constraint of the lowest social welfare level by considering the speculative behavior of the cost innovation in the operation stage of the social capital side. The results show that there is a U-shaped relationship between the comprehensive cost of the project and the shareholding ratio of the social capital, and the social welfare level will decrease with the increase of the shareholding ratio of the social capital. Therefore, the government should consider the cost advantage, financing cost and social welfare level of social capital in a comprehensive manner, and determine the optimal ownership structure to realize the Pareto efficiency of capital utilization and improve the supply quality and efficiency of public service. [ABSTRACT FROM AUTHOR]

Using the newly released data by the research team of China's Urban Household Consumer Finance, this paper explores the effect of health on Chinese urban household financial asset allocation. It has been found that such variables as health status, economy and demography may exert varied effects on the different types of urban household financial assets. Health deterioration tends to reduce the financial assets, especially the risk assets, which are held by urban households. The proportion of risk assets held in the east is higher compared to the central and western regions. A household in good condition has a 2%~3% higher probability of holding risk assets than the one in poor health. The effect of economy on financial asset holding is fundamental. [ABSTRACT FROM AUTHOR]

A phase control method of stall flutter suppression with synthetic jet (SJ) is presented in this paper. Based on the theory of thin-walled composite beams with closed sections, a dynamical model of three-dimensional wings is developed and the flow field around the wing under SJ action is also investigated with CFD software. The results show that the phase of vortex shedding could be controlled with SJ action under certain conditions. Based on this discovery, it is proposed to suppress the stall flutter by lowering the amplitude of the projective fluctuating aerodynamic loads on each of the modes. The effectiveness of our method is numerically verified by taking the NACA0012 airfoil as a case study. If the phase difference of SJ action on the wingspan is large enough, the resonant amplitude of the first bending mode and the first torsion mode will be reduced to about 6%, and those of the second modes will be decreased to about 10%. [ABSTRACT FROM AUTHOR]

Coal mining inevitably leads to the ecological damage in mining areas. Most of the researches and practices placed an emphasis on artificial restoration in the past research activities. However, the differences among self-healing, natural restoration and artificial restoration should be distinguished, which could benefit the cost and effectiveness of reclamation. Based on introduction of the concept of ecological restoration for mining areas, the interrelations of self-healing, natural restoration and artificial restoration were discussed, and a cost-effective strategy for mining ecological restoration represented in this paper. The research shows that the progresses of the damaged natural environment repaired by artificial or natural power are called artificial restoration and natural restoration, respectively. The self-healing of ecosystem and natural restoration are both relying on the natural power, which are all identified as the natural restoration. The self-healing of mining ecological environment means that a part of damage is recovered automatically by mining driving force during the process of ecological damage, which is in the process of mining. Based on the theory of mining subsidence, the mechanism of the self-healing was revealed. Therefore, ecological restoration caused by coal mining should follow some principles: firstly, the damage characteristics must be analyzed and the possibility of self-healing and natural restoration should be determined; secondly, the districts of self-healing, natural restoration and artificial restoration should be classified and corresponding restoration planes could be made; thirdly, self-healing and natural restoration should be paid much attention in fragile ecology region and artificial restoration should be reduced as much as possible, so the natural succession and ecosystem balance can be realized. [ABSTRACT FROM AUTHOR]

The shortage and potential contamination of the materials of filling reclamation of mining subsidence land in plain area with high groundwater level is serious. In order to analyze the feasibility of Yellow River sediment used as the filling reclamation material of mining subsidence land, nine soil profile samples of the control farmland and three surface sediment samples of the Yellow River shoal at the upstream of Chengai diversion gate in Liangshan County of Jining City were collected. Soil texture, pH, electrical conductivity, organic matter, nutrient substance and eight heavy metals (As,Cd,Cr,Cu,Ni,Pb,Zn,Hg) were analyzed by ICP-AES and other methods. The results indicate that the texture type of Yellow River sediment is sandy soil and its capacity to retain water and nutrients is poor; the pH of Yellow River sediment is weakly alkaline, electrical conductivity is very low, but they can meet the requirement as the reclaimed material; the contents of organic matter, total nitrogen, available nitrogen, total potassium, available potassium, total phosphorus and available phosphorus of Yellow River sediment are at the levels of middle, low or very low and its fertility needs to be improved as the reclaimed material; Cd and Hg are not detected in the Yellow River sediment, and the contents of Cr, Cu, Zn, Pb, Ni and As are less than the first and second level values of Environmental quality standard for soils (GB 15618-1995), it won't cause pollution as the filling reclamation material. It's feasible for Yellow River sediment used as the filling reclamation material of mining subsidence land, but its fertility and capacity to retain water and nutrients need to be improved. [ABSTRACT FROM AUTHOR]

Treatment of coal gangue piles with spontaneous combustion has a heavy demand to inert materials. To reach the aims; saving soil, utilization of waste and ensuring environmental benefits, the study on the optimum volume ratio of fly ash to replace partial soil as covering materials for coal gangue piles with spontaneous combustion is purposeful. Fly ash was mixed evenly with silt, silt clay according to different volume ratio. Through the indoor simulation experiment, air isolation effectiveness of different ratio mixed materials of soil and fly-ash was tested, and the influence of fly-ash with different volume to the air barrier property of hybrid materials was analyzed. The results show that, when mixed fly-ash in silt-clay and silt, the air barrier property of mixed materials decreases steadily with the increasing of fly-ash, and approximate expressions respectively shows as an exponential function between permeability and fly-ash content at various pressure differentials. Ash content of 50% and 30%, respectively, determines the isolation changes, which is an important characteristics. It suggests that fly ash content is less than 50% and 30% respectively in silty-soil and in silt-clay. [ABSTRACT FROM AUTHOR]

In order to develop the key association loci for soybean oil and protein content , ninety - two soybean cultivars or germplasm of China Northeast area were selected to be analyzed for oil and protein content based on Meta , and to be analyzed and estimated for the population structure based on mathematic model. The loci associated with oil and content were analyzed by employing the general linear model. The results showed that the population was divided into 5 sub - population when K value was 5 by multiple sample test. The oil content associated markers with contribution >1% included Sat_412 , Sat_195 , Satt317 , Sat_187 , Sat_195 , Satt255 , Satt713 , Satt468 , Satt267 , Satt686 , Sat_294 , AZ302047 and contributed to oil content with a total of 39. 54% at p <0. 05 significant level. The protein content associated markers include Satt683 , Sat_311 , Satt578 , Satt181 , Satt317 , Satt700 , Satt713 , Satt255 , Sat_242 and Satt720 with a total of 48. [ABSTRACT FROM AUTHOR]

Coal mining might cause serious environmental damage in ecologically fragile region. In sandy and windy region, ground fissure is the most typical characteristic of ecological damages caused by underground coal mining. However, few works and reports are related to the generation and whole development process of ground fissures caused by high tension and rapid caving mining. Through the united space coordinates control system at surface-underground, a comprehensive observation method was invented to monitor ground fissure on the No. 12406 working face of Bulianta coalfield, distribution characteristic of marginal fissures, genesis and development rules of dynamic fissures and their relationship with mining geological conditions were revealed. The results show that: ➀Dynamic fissures always develop ahead of the current working location, the crossover distance has a significant positive linear correlation with size of daily footage. The average fissure crossover distance is 10. 359 m and advance angle of break is approach to vertical angle. ➁ Under the high tension and rapid caving mining, dynamic ground fissures havn't obvious heads in vertical direction,those widths had similar cyclical changes during the mining process and present 'M' type with two different peaks. The first peak (maximum width) is 1.4-3. 8 times of the second one. The life-cycle of a dynamic fissure is 18 days,including two cracking-closure processes with similar duration. On this basis,a common function model for the life-cycle was established based on mining and geological conditions. It indicates that dynamic fissures have fast 'self-healing' features and manual repairmen might not be necessary. ➂ Marginal fissures occurrs in strips and the '0' shape inside of boundary working face, and the width of strip of marginal fissures is about 46-50 m. If the adjacent coal face excavates, the width of the strip of marginal fissures in this side will be narrowed 40% due to the double disturbance. The distribution region of marginal fissures will exist long time and need manual restoration. [ABSTRACT FROM AUTHOR]

Based on the comparison between reforested 19-year-old Mytilaria laosensis and Cunninghamia lanceolata plantations on cut-over land of C. lanceolata, effects of tree species transfer on soil dissolved organic matter were investigated. Cold water, hot water and 2 mol · L-1 KCl solu- tion were used to extract soil dissolved organic carbon ( DOC) and dissolved organic nitrogen (DON) from 0-5, 5-10 and 10-20 cm soil layers. In M. laosensis plantaion, the concentrations of soil DOC extracted by cold water, hot water and 2 mol · L-1 KCl solutions were significantly high- er than that in C. lanceolata plantation. In the 0-5 and 5-10 cm layers, the concentrations of soil DON extracted by cold water and hot water in M. laosensis plantation were significantly higher than that in C. lanceolata plantation. The extracted efficiencies for DOC and DON were both in order of KCl solution>hot water>cold water. In the 0-5 cm layers, soil microbial biomass carbon (MBC) under M. laosensis was averagely 76. 3% greater than under C. lanceolata. Correlation analysis showed that there were significant positive relationships between hot water extractable organic matter and soil MBC. Differences in the sizes of soil DOC and DON pools between the M. laosensis and C. lanceolata forests might be attributed to the quality and quantity of organic matter input. The transfer from C. lanceolata to M. laosensis could improve soil fertility in the plantation. [ABSTRACT FROM AUTHOR]

The geochemical characteristics of the rare earth element contents in Yimin lignite were analyzed by using ICP-MS and conventional chemical analysis methods. The results show that the rare earth element in Yimin lignite mainly occurs in clay minerals and titanium-containing minerals, and less being in pyrite, carbonates, sulfates, which result in dilution effect. Meanwhile, a complementary relationship on the occurrence of the rare earth dements in humic acid extracted from demineralized coal and residue was found. The relative enrichment degree of rare earth elements in the humic acid extracted from demineralized coal is light rare earth element (LREE) < medium rare earth element (MREE) MREE > HREE, which suggest that the distribution of rare earth elements in the organic matter is characterized by HREE mainly occurs in humic acid while LREE are in the major organic structure of coal. [ABSTRACT FROM AUTHOR]

This paper aimed at the problems such as low restoration rate of land resources and long time for subsidence land reclamation by traditional technology with the condition of final subsided status. Based on the introduction and discussion of the research history for unsteady subsidence land reclamation, the concept of concurrent mining and reclamation (CMR) was proposed. The connotation, principles, technical classifications, and key technologies of CMR for underground coal mining were presented. The advantages with high reclamation percentage of land resources for the new technology were proved based on a case study, which indicated that CMR could increase farmland reclamation percentages to 37. 59% comparing with the farmland reclamation percentage of post-mining. The scope of application and application prospects of the technology were also discussed, CMR could be used in 5 of the 14 large coal bases. It is estimated that the application of CMR could increase land area by 6 680. 8 km². [ABSTRACT FROM AUTHOR]

A comparative study was conducted on the soil C and N pools in a 19-year-old broadleaf plantation and a Chinese fir (Cunninghamia lanceolata) plantation in subtropical China, aimed to understand the effects of tree species on the soil C and N pools. In the broadleaf plantation, the C and N stocks in 0-40 cm soil layer were 99. 41 Mg ⋅ hm-2 and 6.18 Mg ⋅ -2, being 33. 1 % and 22. 6 % larger than those in Chinese fir plantation, respectively. The standing biomass and the C and N stocks of forest floor in the broadleaf plantation were 1. 60, 1. 49, and 1. 52 times of those in Chinese fir plantation, respectively, and the differences were statistically significant. There was a significant negative relationship between the forest floor C/N ratio and the soil C and N stocks. In the broadleaf plantation, the fine root biomass in 0-80 cm soil layer was 1. 28 times of that in the Chinese fir plantation, and the fine root biomass in 0-10 cm soil layer accounted for 48. 2 % of the total fine root biomass. The C and N stocks in the fine roots in the broadleaf plantation were also higher than those in the Chinese fir plantation. In 0-10 cm soil layer, its C stock had a significant positive relationship with the fine root C stock. It was suggested that as compared with Chinese fir plantation, the soil in broadleaf plantation had a greater potential to accumulate organic carbon. [ABSTRACT FROM AUTHOR]

The fierce competition of market and the complexity of technological innovation inevitably lead to the syriergia of higher education institutions and enterprises. Such a synergetic development of technological innovation system by higher education institutions and enterprises is impacted by both internal and external factors. The synergetic development of schools and enterprises in technological innovation requires higher education institutions to reinforce contact and communication with enterprises, while enterprises are supposed to pass on the market demands and developmental tendencies to higher education institutions. What is more, the policy service system of synergetic technological innovation needs to be improved, a diversified and multi-channel technological investment system should be set up, and the relevant laws and regulations should be strengthened. The orderly operation of the synergetic technological innovation system by higher education institutions and enterprises results from the synergetic effects of the elements within the system. [ABSTRACT FROM AUTHOR]

In order to improve the tracking accuracy of acquisition, tracking, and pointing (ATP) system of the laser communication, the method of discrete sliding mode control based on an exponential reaching law is presented in this paper. The tracking control model of the ATP system was established and the fine tracking system with sliding mode control was designed. Simulation of the dynamic lag tracking using designed system was conducted. The results show that, compared with conventional frequency domain method, the sliding mode control could increase control bandwidth and improve the stability and dynamic performance of the system. In addition, the coarse residual error of the system would be effectively suppressed in a wide range. [ABSTRACT FROM AUTHOR]

Teachers' practical knowledge is multiple in its construction, which lies in theoretical, technological and intellectual respects. Teachers' practical knowledge, whether it is theoretical, technological or intellectual, can be found in both teachers' individual practice and their developmental stages. [ABSTRACT FROM AUTHOR]

A low temperature controllable absorption cell was established, which can calibrate the concentration of gas. The atmosphere radiation transfer software ARHiRS was used to compute the absorption of the cell. The experimental result indicates that, due to the difference of the external and internal temperature of the cell, which was in the condition of 1 m in length and full filled with CO2at 1.01 X 105 Pa, the internal temperature distribution is nonuniform. The simulation demonstrates that, the error caused by the effect of nonuniform temperature distribution on the absorption transmission of gas is no more than 0.05%, and the error of the concentration inversion does not exceed 0.8%. It is concluded that the established absorption cell can meet the needs of the concentration calibration. [ABSTRACT FROM AUTHOR]

Objective To investigate the role of inhibitor of DNA binding-1 (Id-1) gene in adenoid cystic carcinoma cell growth and invasion behavior. Methods With salivary adenoid cystic carcinoma cell lines ACC-M and ACC-2, dedected Id-1 gene expression was screened with immunofluorescence assay. After Id-1 mRNA knocking-down using small interfering RNA, RT-PCR and Western blot were used to detect the different expressions before and after interference, and the growth of cells before and after interference was deceted using the MTT assay, and the cell invasion ability was checked with the use of Transwell chamber assay. Results Id-1 were both expressed in the ACC-M and ACC-2, and the expression in ACC-M was higher than that in ACC-2. After Id-1 RNA interference, the growth and invasiveness of ACC-M and ACC-2 were inhibited with the restrained degree in ACC-M much stronger than that in the ACC-2. Conclusion In view of the important role of Id-1 in the behavior of growth and invasion in ACC cell, interfering the expression of Id-1 gene is expected to be a novel and effective means for the treatment of adenoid cystic carcinoma. [ABSTRACT FROM AUTHOR]

Suspension rubber mount's deflection is studied when input signal's frequency and amplitude are in different state. The final dynamic model is based on Bouc-Wen classic model; frequences and amplitude factor are also imported into the dynamic math model. The mount hysteretic nonlinear model is added into the linear vibration system, and the mount deflection time response is able to be calculated by using the vibration of bodywork obtained by linear system as input power. In the situation of sine excitation of same amplitude, the mount deflection amplitude is increased along with input frequency; the area closed in hysteretic curve is also increased along with input frequency, which means that the absorbed energy is increased. The suspension mount is helpful to reduce the vibration of high frequency. [ABSTRACT FROM AUTHOR]

It is necessary that developing dynamic performance model to analysis effect on suspension by mount. The key step is developing the right math model based on experiment, bilinear restoring force model is suitable for mount hysteretic curve, the force of restitution is the summation of linear rigidity force, third order rigidity force, linear damping force and bilinear restoring force, the coefficients are identified by energy method. The curves of coefficients via frequencies and amplitudes are done by calculating the test data, frequency and amplitude effect on coefficients is also mentioned. Damping coefficient is decreasing when vibration frequency was increased; rigidity linear coefficient is increased and third order coefficient is decreasing when vibration amplitude was decreasing. [ABSTRACT FROM AUTHOR]

The irrigation infrastructures are public goods, farmers will adopt free-riding strategy in the management and maintenance because of the individual rationality, and so there are only few people engage in the activity. The paper first established the normal model of farmers engaged in the activity, then designed a new manage model by appropriate incentives and organization forms. Farmers not only individual rationality but also can change them strategies by study, so the paper discussed the cooperation and strategy change of the farmers by evolutionary game based of Q-learning. At last, the simulation illustrated that the new model not only improved the income of the upstream and downstream farmers, but also can increase the degree of cooperation in the game. [ABSTRACT FROM AUTHOR]

Detecting the air barrier property of covering layer of coal gangue is the major problem, which needs to be studied and solved in the treatment practice of coal gangue piles with spontaneous combustion. It is also the urgent requirement for monitoring compaction effect of covering layers of coal gangue piles with spontaneous combustion. Authors developed a testing equipment of air permeability under the conditions of large-size soil samples, which can directly test the air barrier property of soil samples by simulating or in-situ sampling the covering layer of coal gangue piles with spontaneous combustion according to the positive pressure difference method, and also can evaluate the effectiveness of stopping combustion by the coveting layer. The equipment includes three parts : airtight chamber, pressure source and measuring elements. Airtight chamber: Diameter is 120 -240 ram, which includes three sealed and connected chambers, the top one is for air injection, bottom one is for exhaust air, the middle one is the place for soil samples. The pressure source : includes the air compressor and air reducing valve. Measuring element includes a barometer, and flow meter or readable air flow meter. To detect the equipment performance, air tightness testing indicate that the equipment in the pressure of 0.2 MPa, can guarantee the closed within 10 hours, can satisfy the overlying soil materials in this test pressure test requirements of effectiveness of stopping combustion. Testing repeatability and data reproduction of the equipment, results show that the deviation coefficient is less than 10%. The air permeability test of a group of fly ash with different compactness was took, it show that the air permeability speed of different samples is increased with experimental pressure differences linearly, and the slope of the linearly model decreases with the increase of the sample compactness. In the range of pressure is less than 0.05 MPa, according to the poor air flow rate through the barrier of Inferior Fly Ash Reynolds number, the results are less than 1. When the compaction under different compactness, then the larger compactness of sample, and the smaller air permeability, good barrier performance, equipment testing results accord with the objective reality. [ABSTRACT FROM AUTHOR]

Based on the study on programming of CFD and DSMC method, a CFD/DSMC hybrid method is established employing MPC principle. A sub-relax technique is adopted to deal with information exchange between CFD and DSMC. Flows around a blunt cone at variation Kn numbers are simulated by the CFD/DSMC hybrid method. Comparison of the calculation results with the related low density wind tunnel test data shows a coincidence between them, which means that the hybrid method is an effective method in lower Kn numbers. The errors are analyzed of the hybrid method. This work is hopeful of developing a useful tool to predict aerodynamic characteristics of hypersonic vehicles in transitional flows. [ABSTRACT FROM AUTHOR]

Objective: To investigate the imaging effect of a near-infrared fluorescent targeted probe ICG-NP41 on the neurovascular bundles (NVB) around the prostate in rats., Methods: A near-infrared fluorescent targeted probe ICG-NP41 was synthesized. An animal model for NVB imaging was established using Sprague-Dawley rats (250-400 g). Experiments were conducted using a custom-built near-infrared windowⅡ(NIR-Ⅱ) small animal in vivo imaging system, and images collected were processed using ImageJ and Origin. The fluorescence signal data were statistically analyzed using GraphPad Prism. The signal-to-background ratio (SBR) for NVB was quantitatively calculated to explore the effective dosage and imaging time points. Finally, paraffin pathology sections and HE staining were performed on the imaging structures., Results: Except for rats in the control group ( n =2), right-sided NVB of the rats injected with ICG-NP41 ( n =2 per group) were all observed in NIR-Ⅱ fluorescence mode 2 h and 4 h after administration. At 2 h and 4 h, average SBR of cavernous nerve in 2 mg/kg group in fluorescence mode was 1.651±0.142 and 1.619±0.110, respectively, both higher than that in white light mode (1.111±0.036), with no significant difference ( P >0.05); average SBR of 4 mg/kg group in fluorescence mode were 1.168±0.066 and 1.219±0.118, respectively, both higher than that in white light mode (1.081±0.040), with no significant difference ( P >0.05). At 2 h and 4 h, the average SBR of 2 mg/kg and 4 mg/kg groups in fluorescence mode were higher than that of the control group (SBR=1), the average SBR of the 2 mg/kg group was higher than that of the 4 mg/kg group, and all the above with no significant difference ( P >0.05). The average diameter of the nerve measured by full width at half maxima method was about (178±15) μm. HE staining of paraffin sections showed the right major pelvic ganglion., Conclusion: The near-infrared fluorescent targeted probe ICG-NP41 can be used for real-time imaging of the NVB around the prostate in rats, providing a potential feasible solution for localizing NVB in real time during nerve-sparing radical prostatectomy.

The pollution of surface waters by pharmaceuticals and personal care products (PPCPs) has aroused widespread concern. Constructed wetlands (CWs) have outstanding advantages in the removal of PPCPs; however, few studies have focused on the interaction of different types of PPCPs in CWs. In this study, two typical PPCPs[broad-spectrum antimicrobial agents triclosan (TCS) and non-steroidal anti-inflammatory drug diclofenac (DCF)] were selected as target pollutants and their removal behavior in subsurface flow CWs was analyzed. The effects of different seasons and influent conditions (i.e., single and combined addition of TCS and DCF) on removal efficiency was also examined. The main parameters of the CW system were as follows:the up-flow subsurface CW had a hydraulic load of 0.20 m·d -1 and a hydraulic residence time of 3 d with a continuous flow inlet. The initial influent concentration of PPCPs was 80 g·L -1 for TCS and 25 g·L -1 for DCF. The results showed that the average removal efficiencies for TCS and DCF in summer (91.72% and 85.86%, respectively) were significantly higher than in winter (52.88% and 32.47%, respectively). Independent sample t -tests confirmed that there was no significant difference in the removal efficiency of TCS and DCF under the different influent conditions (single and combined addition). The degradation products of TCS and DCF were also no different between the influent systems, and the representative degradation products of TCS were not detected in all systems. The main degradation products of DCF in the different systems were 3,5-dichlorobenzoic acid and m-dichlorobenzene. The two studied PPCPs showed no significant antagonism and competition effects at trace levels.

Objective: To study the effect of traditional chinese medicine (TCM) compound on myeloid leukemia cells and to explore its anti-leukemic mechanism., Methods: Myeloid leukemia cell lines were cultured in vitro and treated with TCM compound. The proliferation of the leukemia cells was measured by CCK8 method. The differentiation of the leukemia cells was evaluated by using Wright＇s staining method and by light microscopy, and the expression of differentiation-related surface antigens such as CD11B was measured and by flow cytometry, the apoptosis of the leukemia cells was detected by flow cytometry with using Annexin V staining., Results: Compared with untreated 4 leukemia cell lines HL-60, MOLM-13, MV4-11, AML-M5, the proliferations of 4 leukemia cells treated with different concentrations of TCM compound decreased (P<0.05), and their proliferation inhibition were in a dose-dependent manner (r=0.9236; r=0.7488; r=0.8889; r=0.8119); compared with HL-60 and AML-M5 leukemia cells, the drug-treated 2 leukemia cells displayed obvious differentiated changes; compared with untreated HL-60 leukemia cell line, the expression of surface antigen CD11B increased by 85%±7.13% in HL-60 cells treated IC50 concentration of drug; compared with untreated AML-M5 leukemia cell line, the apoptotic rate of AML-M5 treated with 1.5 and 2 μl doses of TCM compound increased. (P<0.05)., Conclusion: The traditional chinese medicine compound may inhibit the proliferation of leukemia cell lines mainly by inducing leukemia cell differentiation and apoptosis.