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This study investigates the fracture characteristics and damage mechanism of granite after treatment under different heating rates. The cracked straight-through Brazilian disc(CSTBD)specimen was used for high-temperature treatment with four heating rates under four sets of heating temperatures. The Brazilian splitting experiments were carried out using electro-hydraulic servo press after cooling down to room temperature, and the static fracture process was analyzed to investigate the effect of heating rate on the fracture mechanical properties of specimens. The results show that: (1) Granite treated at different high temperatures shifted from brittle to ductile damage. (2)The peak damage load of granite treated with different heating rates at the same temperature decreased with the increase of heating rate. At the same temperature, the increase of heating rate doesn't lead to obvious difference in the apparent color of granite, but with gradual increase of apparent cracks. (3)At different heating rates, the longitudinal wave velocity and elastic modulus at 200 ℃ and 400 ℃ show subtle changes, yet at 600 ℃ and above, the longitudinal wave velocity and elastic modulus decrease significantly with the increase of heating rate. (4) The fracture toughness of granite shows gradual decay with the increase of temperature. At the same temperature, type I fracture toughness of granite specimens decreases with the increase of heating rate. At 400 ℃, heating rate exerts maximum influence on the fracture toughness of granite.

The standardized workflow of computer-aided static guided implant surgery includes preoperative examination, data acquisition, guide design, guide fabrication and surgery. Errors may occur at each step, leading to irreversible cumulative effects and thus impacting the accuracy of implant placement. However, clinicians tend to focus on factors causing errors in surgical operations, ignoring the possibility of irreversible errors in nonstandard guided surgery. Based on the clinical practice of domestic experts and research progress at home and abroad, this paper summarizes the sources of errors in guided implant surgery from the perspectives of preoperative inspection, data collection, guide designing and manufacturing and describes strategies to resolve errors so as to gain expert consensus. Consensus recommendation: 1. Preoperative considerations: the appropriate implant guide type should be selected according to the patient's oral condition before surgery, and a retaining screw-assisted support guide should be selected if necessary. 2. Data acquisition should be standardized as much as possible, including beam CT and extraoral scanning. CBCT performed with the patient’s head fixed and with a small field of view is recommended. For patients with metal prostheses inside the mouth, a registration marker guide should be used, and the ambient temperature and light of the external oral scanner should be reasonably controlled. 3. Optimization of computer-aided design: it is recommended to select a handle-guided planting system and a closed metal sleeve and to register images by overlapping markers. Properly designing the retaining screws, extending the support structure of the guide plate and increasing the length of the guide section are methods to feasibly reduce the incidence of surgical errors. 4. Improving computer-aided production: it is also crucial to set the best printing parameters according to different printing technologies and to choose the most appropriate postprocessing procedures.

YOLOv3 algorithm is characterized by high detection accuracy and high speed in the aspect of target detection and recognition. It is outstanding among similar algorithms, but there are still obvious problems. The loss operation of the wide and high part of the loss function of this algorithm is not obvious to the distinction between the big target and the small target, which leads to the problem that the loss calculation is not accurate enough and the prediction box size of the small target is not accurate. In view of this defect, the loss function of YOLOv3 algorithm was improved, the wide-height coordinate error was modified into the form of proportion, the non-maximum suppression method of the original model was improved and the overlap threshold was changed from the fixed value to the form of attenuation function. Finally, the model was applied to vehicle detection. The experimental results showed that the improved model improved the accuracy rate, recall rate and F1 value to different degrees while basically not affecting the vehicle detection speed, making the overall performance of the model better than the original YOLOv3 model.

Ultra high pressure common rail system can realize adjustable injection rate by controlling the relationship between fuel injection and pressurization timing, and then affect the fuel injection characteristics of diesel engine. In order to ascertain the effect law and its formation mechanism of the fuel injection and pressurization pulse width on the fuel injection characteristics of ultra high pressure common rail system, on the basis of introducing the mathematical model of the system, the simulation model of ultra high pressure common rail system was established, and the accuracy of the model was verified by performance experiment, the effect of fuel injection and pressurization pulse width on the fuel injection characteristics of the system under different common rail pressure were analyzed. The results show that with the increase of fuel injection pulse width, the shape of fuel injection rate curve is similar to saddle shape and the proportion of large fuel injection rate range in the whole injection process increases gradually. At the same time, the fuel injection opening delay remains unchanged, but the fuel injection closing delay increases significantly when the fuel injection pulse width is small (0.6~1 ms), while it remains basically unchanged when the fuel injection pulse width is large (1~1.4 ms). With the increase of pressurization pulse width, the shape of fuel injection rate curve is similar to saddle shape and remains unchanged under the condition of small injection pulse width, while the fuel injection rate curve shape may appear similar to the "inverted saddle-shaped" under the condition of large injection pulse width, this is due to the rapid decrease of pressurization pressure caused by the closing of the solenoid valve control signal in the pressure-amplifier device before the end of fuel injection.

Objective Geomechanical analysis plays a crucial role in exploring and developing oil and gas reservoirs. However, the study of in-situ stress in the Yijianfang–Yingshan formations of the Middle to Lower Ordovician in the Shunbei oilfield has lagged behind. This paper compares and analyzes the rock mechanics and in-situ stress characteristics of different types of carbonate reservoirs in the Yijianfang-Yingshan formations of the Lower Paleozoic Ordovician in the Shunbei No. 4 block, and explores the control effect of micro-grain structures on the in-situ stress and rock mechanics parameters of carbonate reservoirs. It aims to provide fundamental geological data for the evaluating of ultra-deep carbonate reservoirs in the Shunbei area. Methods This study, based on the spring combination model, determined the rock mechanics and in-situ stress characteristics through rock mechanics experiments and array acoustic logging, and characterized the micro-pore structure of the limestone using casting thin sections and X-ray μ-computed tomography analysis. Results The results indicate that the Young's modulus of the Yijianfang–Yingshan formations ranges from 50 to 89 GPa, the compressive strength from 99 to 136 MPa, and the Poisson's ratio from 0.25 to 0.32. The maximum horizontal principal stress of the formations ranges from 200 to 225 MPa, while the minimum horizontal principal stress ranges from 125 to 160 MPa. Conclusion Significant differences in rock mechanics parameters and in-situ stress exist among different types of carbonate reservoirs in the Yijianfang–Yingshan formations. From Type I to Type III and non-reservoir carbonate rocks, the Young's modulus, compressive strength, and maximum horizontal principal stress increase dramatically, while the Poisson's ratio and minimum horizontal principal stress show little change. Compared to micritic limestone, sandy–bioclastic limestone has larger calcite particles and reduced particle cohesion, resulting in decreased compressive strength and Young's modulus. Some calcite particles appear sub-rounded or rounded with higher three-dimensional particle sphericity, also leading to weaker intergranular engagement and further reduction in compressive strength and Young's modulus. The presence of numerous pores and fractures in sandy-bioclastic limestone facilitates frictional sliding and potential failure along microfractures or particle interfaces, contributing to lower compressive strength and Young's modulus as well. In addition, micritic limestones in the Yijianfang–Yingshan formations are affected by hydrothermal activity, with some dolomite being replaced by quartz, which increases the compressive strength and Young's modulus. The macroscopic mechanical characteristics and rock mechanics parameters of the rock are constrained by the micro-grain structures. The low-value zones of the Young's modulus, compressive strength, and maximum horizontal principal stress in the Yijianfang–Yingshan formations are identified as the advantageous reservoir development zones in the Shunbei No. 4 block.

Objective To analyze the clinical characteristics of Legionnaires’ disease in immunosuppressive patients， and to explore the significance of blood metagenomic next-generation sequencing （mNGS） in the early diagnosis and treatment of Legionnaires’ disease in immunosuppressive patients. Methods A patient with angioimmunoblastic T-cell lymphoma who developed pulmonary infection after chemotherapy was reported. The diagnosis of Legionella pneumophila infection was confirmed by blood mNGS. Using “Legionella” “blood” “metagenomic next-generation sequencing” and “mNGS” as the keywords in both Chinese and English， relevant studies were searched from CNKI database， Chinese core journals and PubMed database. Clinical data of patients positive for Legionella pneumophila by blood mNGS were analyzed. Results The female patient， aged 50-year-old， was admitted to our hospital due to “the diagnosis of angioimmunoblastic T-cell lymphoma and continuing chemotherapy for more than 10 months”. After twice intravenous chemotherapy， the patient was complicated with myelosuppression， cough and fever. The possibility of pulmonary infection was considered. Conventional antibiotic therapy yielded low efficacy. Blood mNGS confirmed the infection with Legionella pneumophila. After adjusted antibiotic treatment （levofloxacin + tigecycline）， the patient was improved and discharged. According to literature review， two cases with complete clinical data were searched. Both two cases were children with hematological diseases who were complicated with pulmonary infection after stem cell transplantation. After the pathogen was identified by blood mNGS， the disease was mitigated after anti-Legionella treatment. Conclusions Immunosuppressed patients with Legionella pneumophila infection are likely to be complicated with bloodstream infection， and clinical manifestations are non-specific. mNGS contributes to prompt identification of the pathogen. Combined anti-infection treatment should be delivered and the course of treatment should be properly prolonged， aiming to lower the risk of progression into severe pneumonia.

Aiming at the urgent demand of unmanned and intelligent border security system, an unattended border monitoring system is designed for weak infrastructure border area. The system composition and sub-system design are introduced, and the key technologies for engineering realization are given, ground surveillance radar and electro-optics device single-site collaborative detection and tracking technology, and multi-target tracking algorithm with intermittent observations are proposed. The realization and demonstration verification test of prototype system prove the scientificity and rationality of the design, which achieve the tactical and technical requirements of high point monitoring with the unattended capability.

Objective To develop a Comprehensive Mental Health Assessment (CMHA) questionnaire for soldiers and test its reliability and validity. Methods With the Military Demand-Resource model as the theoretical conception, and psychological measurement, statistical analysis, expert evaluation, collective discussion as the research method, a pre-questionnaire containing 98 items was revised based on the prediction of 935 soldiers. Another 1 689 soldiers were selected from basic army units to test the reliability and validity of the questionnaire using cluster sampling. Results The formal CMHA questionnaire contained 94 items and 12 factors (adaptability, positive coping, depression, negative emotion, positive emotion, work involvement, loneliness, friendship, family satisfaction, institutional trust, interpersonal trust and life meaning). The internal consistency coefficient of the total questionnaire was 0.978. The test-retest reliability coefficient was 0.756 (P < 0.01). Confirmatory factor analysis supported the 12-factor model, and fitted well with the measured data. Conclusion Our prepared CMHA questionnaire has good reliability and validity and is an effective tool to measure soldiers' multidimensional mental health.

The multi-stage tectonism of compression and extension occurred in the southern part of the Lower Yangtze region in the Mesozoic, which is one of the important factors restricting the breakthrough of oil and gas exploration in this area. This paper aims to reveal the influence of Mesozoic tectonisim on oil and gas preservation in the Lower Yangtze area. Based on the seismic profile interpretation data, field outcrop survey, regional tectonic evolution history analysis and the drilling core data and oil-gas display of the Well Wanjingdi-1, we comprehensively discussed the favorable structural preservation conditions in the southern part of the Lower Yangtze region. The results of seismic interpretation profile and surface survey show that the southern part of the lower Yangtze River has experienced two important tectonic processes since the Late Triassic. The first stage is fold deformation, thrust fault and uplift erosion caused by Indosinian compression, and the second stage is extension since the Late Cretaceous, resulting in the formation of fault basin and normal fault activity. Shale gas display was obtained from the Permian shale in the Well Wanjingdi-1, and light oil was found in the drilling of the Lower Triassic Yinkeng Formation, indicating that the southern Lower Yangtze region has good enrichment conditions and resource potential, which points out a new direction for oil and gas exploration in the region. The analysis of structural preservation conditions shows that the Well Wanjingdi-1 is located in the syncline of the fold-depression belt. The amount of uplift and denudation was small in the Indosinian period. Since the late Cretaceous, the depression has a small amplitude of extension and has good sealing and reservoir forming conditions. It is a favorable structural position for oil and gas preservation in this region. Based on the comprehensive analysis of regional structure and sedimentary basin evolution, it is considered that in the southern Lower Yangtze region, the syncline structural belt in the southern margin of the basin with small erosion amount of Triassic strata or the central zone of fault basin overlying thick Cretaceous-Cenozoic strata should be taken as the key target to search for favorable oil and gas zones.

In conventional airfoil optimization design method, the aerodynamic performance of the optimal airfoil can deteriorate at the non-design point, so it is necessary to study the airfoil robust optimization method.An airfoil robustness design method based on convolutional neural network and polynomial chaos method is proposed.Firstly, an aerodynamic force prediction method based on convolutional neural network model is established.And then, the polynomial chaos method is used to perform the uncertainty quantification for mach number and attack angle, a design system of airfoil robust aerodynamic optimization is constructed.Finally, the optimization design verification is carried out for the aerodynamic optimization design problem, in which the RAE2822 airfoil is taken as the basis airfoil.The results show that the robustness design method of the airfoil proposed in this paper is feasible, the optimized airfoil aerodynamic performance and robust aerodynamic optimization design efficiency are improved in a wide design range.

Because nanoparticles have particular characteristics, such as small size and surface effects, nano⁃TiO2 is widely used in air purification, wastewater treatment and self⁃cleaning. In recent years, TiO2 photocatalysis has thorough⁃ ly explored as a new titanium implant surface treatment method. Photocatalytic performance is better for TiO2 nanowires than for nano⁃TiO2 particles. Hence, these nanowires have received widespread attention with regard for their more spe⁃ cific surface area and surface energy, improved charge carrier transport efficiency, and enhanced charge collection effi⁃ ciency. Photon⁃generated carrier transport moves in a one dimensional straight path along a nanowire, and this could de⁃ crease photoelectron loss. In this paper, we summarized the principles underlying, factors that influence, and applica⁃ tions involving TiO2 nanowire photocatalysis. Additionally, we describe its method of preparation and toxicity

Carbon nanotubes (CNTs, mass fraction of 0%-2%) reinforced Al5083 composites were fabricated by horizontal high-energy ball milling. The effects of ball milling time and CNTs contents on the properties of composite materials were studied. The micro morphology of CNTs/Al5083 composites was characterized by scanning electron microscopy(SEM) and transmission electron microscopy(TEM), the tensile strength and microhardness of the composites were tested. The results indicate that after high-energy ball milling for 1.5h, the carbon nanotubes are dispersed homogeneously in the Al5083 matrix, and good interfacial bonding strength between CNTs and Al5083 is obtained at the addition of 1.5%CNTs. Under these conditions, the tensile strength and microhardness of CNTs/Al5083 composites are 188.8MPa and 136HV, respectively. Compared to Al5083 matrix without CNTs reinforcement, tensile strength and microhardness of CNTs/Al5083 composites are increased by 32.2% and 36%, respectively.

Dental implant restoration is an effective way to restore the chewing and aesthetic function for edentu⁃lous. However, dental implant restoration is facing great challenges of the lack of available bone, the maxillary sinus or inferior alveolar nerve vascular bundle, which is often necessary to carry out the related bone augmentation operation. All⁃on⁃Four technique is to use four implants in the anterior part of complete edentulous jaws, the two most anterior im⁃ plants are placed axially whereas the two posterior implants are placed distally angled, to support a provisional, fixed, and immediately loaded prosthesis. The technique avoids the artificial bone substitutes implantation and maxillary sinus augmentation or other bone augmentation surgery. Besides, it could alleviate patients' psychological reaction, postopera⁃ tive reaction, as well as time and money costs. It is considered a feasible treatment method to combine the application of the oblique implant and the axial implant in the treatment of the edentulous patients. This paper will elaborate on the concept of All⁃on⁃Four, the conventional technology, the evaluation research and some new viewpoints.

The composite powders of 2%-CNTs were prepared by wet ball milling and hydrogen annealing treatment-cold pressing sintering was used to consolidate the ball milled composite powders with different modifications of the CNTs. The results show that the length of the CNTs is shortened, ports are open, and amorphous carbon content is increased by ball milling. And after a mixed acid purification, the impurity on the surface of the CNTs is completely removed,and a large number of oxygen-containing reactive groups are introduced; the most of CNTs can be embedded in the Cu matrix and the CNTs have a close bonding with the Cu matrix, forming the lamellar composite structure, then, ultrafine-grained composite powders can be obtained by hydrogen annealing treatment. Shortening and purification of the CNTs are both good for dispersion and bonding of CNTs in the Cu matrix, and the tensile strength and hardness of the composites after shortening and purification reaches the highest, and is 296MPa and 139.8HV respectively, compared to the matrix, up to 123.6% in tensile strength and 42.9% in hardness, attributed to the fine grain strengthening and load transferring.

Objective To explore the effect and changes in osteogenesis efficacy of CHA (Coral hydroxyapatite) com⁃ posite grafts with fluoride in guided bone augmentation on rabbit skull. Methods Twenty ⁃ four rabbits were studied. Y500R CHA composite grafts contained fluoride and titanium cylinders were prepared. Two titanium cylinders on the test group's rabbit skull were filled with composite grafts contain fluoride and non⁃fluoride grafts were filled in the control group. Cyclomycin and calcein were injected, After 2, 4 and 6 weeks, the animals were sacrificed to obtain ground sec⁃ tions for histology and histomorphometry. The general observation and area of highly fluorescent band of new bone forma⁃ tion was measured after sample treatment. Results Significantly more neogenesis bone was augmented in the test groups than the control group. The osteoplastic effect in the test group more athletic. The experimental data had statistical signifi⁃ cance (F = 6.36, P = 0.019 3). Conclusion Low concentration (1.0 × 10⁃7 mol/L ～ 5.0 × 10⁃5 mol/L) fluoride can pro⁃ mote bone formation effectively.

Objective To study the animal model suitable for the observation of early osteogenesis on the surface of titanium implant. Methods Modify implants mode which the outer thread of the implant next to the osteotomy bone wall while the inter thread keep a certain distance to osteotomy bone wall was adopted in the 1-year-old male Beagle dogs.After extraction of all mandibular premolars and first molar bilaterally in the 4 dogs, 20 implants replaced the position. All sections were stained for histological analysis. Results The surgical wound in the 4 dogs healed by first intention. The titanium implants have good stability. The formation of the new bone, which include the contact osteogenesis and distanceosteogenesis, was observed as it progressed not only in the surface of the osteotomy bone wall but also in the surface of the implants. Conclusion The established animal model is suitable for the observation of both early osteogenesis in implant and the influences of implant surface properties to the early osteogenesis.

Based on the differential kinematics of parallel mechanism displacement vector differential mapping relation between input and output,through establishing a planar 3-RPR topology optimization model of fully compliant parallel mechanism（ SIMP interpolation model）,the solution is optimized by using the optimization criterion method（ OC） algorithm,and by using the Heaviside filtering technology,the checkerboard phenomenon is restrained and processed. Combining with quadratic interpolation method of topology optimization,the curve fitting of the model is carried out,and the 3D model is created in the Solidworks,the model is imported into Hyperworks for second meshing and its statics comparison and analysis are carried out,the results show that,the manipulator which based on the mapping relation of topology optimization not only has the same movement characteristic with the traditional parallel mechanism,but also the structure is more compact,lightweight,and the method provides a theoretical reference for the configuration synthesis of this kind of plane compliant parallel mechanism.

By establishing apseudo-rigid-body model of the planar 3-RRR type fully compliant parallel mechanism,and using micro approximation algorithm,the displacement jacobian matrix between the input and output is got,the displacement vector differential mapping relation between input and output under the micro motion case is researched,and the numerical validation is carried out,the simulation of it is conducted with ANSYS software,the theoretical reference basis for differential motion analysis of this kind of planar parallel mechanism and spatial parallel mechanism with multiple input and multiple output characteristics is provided.

A 5VA environmentally friendly flame retardant polypropylene (PP) composites was prepared using a twin-screw extrusion mechanism. The effects of flame retardant addition, flame retardant surface treatment, and twin-screw thread combination on the flame retardancy, physical and mechanical properties, and production status of PP composites were studied. The results show that when the flame retardant content is 33%, the flame retardancy of PP composites reaches 5VA level, but it significantly reduces the tensile strength, elongation at break, impact strength, and melt flow rate. Silane coupling agents, titanate coupling agents, and silane wax treated flame retardants have improved the toughness and flowability of 5VA environmentally friendly flame retardant PP composites, with the best effect of silicone wax. In scaled up production, SK deep thread components are added to the cutting end of the thread combination to compact the material, and internal mixing and SME components are added to reduce shear and promote dispersion, effectively solving the problems of foaming and difficult pulling of 5VA grade flame-retardant PP composites that prevent normal production. [ABSTRACT FROM AUTHOR]

The dynamics of soil arthropod communities in annual monoculture grasslands is still unclear, which restricts the understanding of the degradation mechanism of cultivated grasslands. We cultivated two annual gramineae species, Lolium multiflorum and Avena sativa, separately in Hongyuan County, located on the eastern edge of the Qinghai-Tibet Plateau, in April 2019. We investigated soil arthropods, plant communities and soil properties in the cultivated grasslands and natural grassland in the late September every year from 2019 to 2022. The results showed that : 1) The taxonomic composition of soil arthropod communities differed significantly among three grasslands and sampling years. 2) There was no significant difference in the density, taxonomic richness, Shannon index and evenness index of soil arthropod communities among three grasslands. 3) The density of soil arthropod communities significantly fluctuated across years in three grasslands, and the taxonomic richness and Shannon index decreased significantly in the L. multiflorum and A. sativa grasslands, with the evenness index declining significantly only in the fourth year. The Shannon index fluctuated significantly and the evenness index varied little in natural grassland. 4) The above- and below-ground biomass, the contents of soil total P, total K and available N were the main factors influencing the taxonomic composition, density and diversity indices of soil arthropod communities. The results suggested that the cultivation of annual gramineae grasslands have significant effects on taxonomic composition, but not on density and diversity of soil arthropod communities, and those variables change significantly across different years. [ABSTRACT FROM AUTHOR]

[Objective] Geomechanical analysis plays a crucial role in exploring and developing oil and gas reservoirs. However, the study of in-situ stress in the Yijianfang-Yingshan formations of the Middle to Lower Ordovician in the Shunbei oilfield has lagged behind. This paper compares and analyzes the rock mechanics and in-situ stress characteristics of different types of carbonate reservoirs in the Yijianfang-Yingshan formations of the Lower Paleozoic Ordovician in the Shunbei No. 4 block, and explores the control effect of micro-grain structures on the in-situ stress and rock mechanics parameters of carbonate reservoirs. It aims to provide fundamental geological data for the evaluating of ultra-deep carbonate reservoirs in the Shunbei area. [Methods] This study, based on the spring combination model, determined the rock mechanics and in-situ stress characteristics through rock mechanics experiments and array acoustic logging, and characterized the micro-pore structure of the limestone using casting thin sections and X-ray μ-computed tomography analysis. [Results] The results indicate that the Young's modulus of the Yijianfang-Yingshan formations ranges from 50 to 89 GPa, the compressive strength from 99 to 136 MPa, and the Poisson's ratio from 0.25 to 0.32. The maximum horizontal principal stress of the formations ranges from 200 to 225 MPa, while the minimum horizontal principal stress ranges from 125 to 160 MPa. [Conclusion] Significant differences in rock mechanics parameters and in- situ stress exist among different types of carbonate reservoirs in the Yijianfang-Yingshan formations. From Type I to Type III and non-reservoir carbonate rocks, the Young's modulus, compressive strength, and maximum horizontal principal stress increase dramatically, while the Poisson's ratio and minimum horizontal principal stress show little change. Compared to micritic limestone, sandy-bioclastic limestone has larger calcite particles and reduced particle cohesion, resulting in decreased compressive strength and Young's modulus. Some calcite particles appear sub-rounded or rounded with higher three-dimensional particle sphericity, also leading to weaker intergranular engagement and further reduction in compressive strength and Young's modulus. The presence of numerous pores and fractures in sandy-bioclastic limestone facilitates frictional sliding and potential failure along microfractures or particle interfaces, contributing to lower compressive strength and Young's modulus as well. In addition, micritic limestones in the Yijianfang-Yingshan formations are affected by hydrothermal activity, with some dolomite being replaced by quartz, which increases the compressive strength and Young's modulus. The macroscopic mechanical characteristics and rock mechanics parameters of the rock are constrained by the micro-grain structures. The low-value zones of the Young's modulus, compressive strength, and maximum horizontal principal stress in the Yijianfang-Yingshan formations are identified as the advantageous reservoir development zones in the Shunbei No. 4 block. [ABSTRACT FROM AUTHOR]

The simulation and optimization was conducted with Aspen Plus on the distillation process for light components in 300,000 tons peryear methylchlorosilane unit. Firstly, WILSON model was selected based on root-mean-square errors (SEs) and absolute average deviation by the experimental data of gas-liquid equilibrium for methylchlorosilanes and the predictions of different thermodynamic models. By comparative analysis of simulation results in different tower sequence, a preferred scheme was that using the original azeotropic tower to prioritize the separation of trimethylchlorosilane, and then the original hydrogen tower and trimethyl tower were connected in series to separate methyl dichlorosilane. The results show that the purity of the methyldichlo-rosilane stream reaches 99.60% with a yield of 99.59%, while the purity of the trimethylchlorosilane stream reaches 99.80% with a yield of 98.40%, with the residual azeotropic flow rate of 68. 34 kg/h, and the total energy consumption of 2361 kW. Additionally, the result verifiy its feasibility by hydraulic analysis. [ABSTRACT FROM AUTHOR]

The production capacity, apparent consumption, product structure and develop trend of TiO2 industry in 2022 have been described. The market situation of TiO2 and its related products is reviewed, such as the upstream industries including titanium mine and sulphuric acid and the downstream industries including coatings, printing inks, plastic, paper making and chemical fiber. Some problems and risks occur in TiO2 industry are analyzed. [ABSTRACT FROM AUTHOR]

Based on the practical application of a new energy vehicle, this paper introduces the factors affecting the cleanliness of the body in white (BIW), and discusses the improvement direction of the cleanliness of the BIW from the sources of welding slag, iron scraps, grease, dust, fibers, control methods and pre-cleaning measures after coating process. Optimization of the BIW cleanliness is one of the important measures to prevent and control the defects of electrophoretic film, by which can ensure the stability of the quality of electrophoretic film. These measures might provide referential value for other vehicle coating processes. [ABSTRACT FROM AUTHOR]

The formation quality and performance of the forming parts are directly affected by the process parameters of laser additive manufacturing. Thus optimizing the process parameters is the most effective way to achieve forming quality regulation. For the prediction of forming quality and the optimization of process parameters, it is extremely important to establish a model describing the relationships between accurate high-precision process parameters and formation quality. In this paper, the method of modeling the optimization of process parameters of laser additive manufacturing were summarized and reviewed, the development of the status quo of process system was also analyzed. The principles, advantages, and disadvantages of the method have been discussed for modeling the optimization of process parameters. Finally, the laser additive manufacturing process optimization modeling research has been prospected. [ABSTRACT FROM AUTHOR]

Jigongshan granite is tin important batholith in Tongbai-Dabie orogenic belt. In order to discuss the petrogenesis and dynamic background of the Jigongshan granite and guide regional prospecting, this paper has carried out zircon U-Pb dating, rock geochemistry and Sr-Nd-Hf isotope studies on the Jigongshan granite. The results show that the pluton is a paraaluminous-weak peraluminous granite, belonging to the high-potassium calc-alkaline series and fractionated I-type granite, accessory mineral includes minor hornblende. Zircon U-Pb dating shows that the age of the Jigongshan pluton is 141.8 ± 0.8 Ma (n = 26, MSWD= 1.15), indicating that the Jigongshan pluton was formed in the Early Cretaceous. The (87Sr/86Sr)i, εNd (t) values and the two stage model age of whole rock are 0. 07 75~0.708 18, -19.21 ~-17. 63 and 2.49-2.36 Ga, respectively. The 176Hf/177Hf, εHf (t) values and the two stage model age of zircon are 0.281 845 ~ 0.282 083, -29.67 ~-21.31 and 3.07 ~ 2.54 Ga, respectively. Sr-Nd-Hf isotopic characteristics suggest that the Jigongshan pluton may be formed by the remelting of Neoarchean middle-lower crust of the Yangtze plate. The granite has high (La/Yb)N, Sr/Y values, and inapparent Eu negative anomalies, similar to the adakite-type granite in the Dabie Mountains. The granite formed in extensional structure, as the product of partial melting of the thickened lower crust that has not yet been delaminated. Jigongshan pluton may be the parent granite of pegmatite vein in the pluton. [ABSTRACT FROM AUTHOR]

ObjectiveTo analyze the HIV infection characteristics and influencing factors among the spouses of HIV/AIDS patients in Shanghai.MethodsA cross-sectional survey was conducted to collect demographic， behavioral， epidemiological and spousal HIV detection information of newly reported and married patients with HIV/AIDS in Shanghai from January 2018 to July 2022 in the comprehensive HIV prevention and control information system of Chinese Center for Disease Prevention and Control. Descriptive analysis was used to analyze the HIV positivity rate of the spouses of HIV patients and the influencing factors were analyzed by univariate and multivariate logistic regression models.ResultsA total of 1 233 subjects were investigated， and the first HIV-testing positivity rate of the spouses of HIV/AIDS patients was 29.3% （361/1 233）. There were statistically significant differences in the HIV-testing positivity rate among spouses of HIV/AIDS patients by different age， gender， education level， occupation， transmission route， quantity of non-marital sexual activities， quantity of homo-sexual activities， and baseline CD4 cell count level （P

In this study, the detection method of caloric value in sludge was established using oxygen bomb automatic calorimeter based on the optimized experimental factors which included drying temperature, drying time, sample weighing amount and combustion supporting material adding amount of sludge sample. Moreover,the difficulty of low caloric value in sludge samp! was also solved. The study shows that accurate and stabe resutts are acquired when the ground sludge sample was fully burned in an oxygen bomb filed with 3.0 MPa oxygen after the drying process of wet sludge. Furthermore, for the detecion of the calorfc value in sludge sampels lower than 7.0 MJ/kg,the accurate results could be obtained wth the add-on of 0. 2 g benzoic acid reference material for the assist of combusion. [ABSTRACT FROM AUTHOR]

In order to solve the problem of low charge and discharge efficiency in graphite anode materials for lithium-ion batteries, low-cost artificial graphite can be used and doped WILL micro-nano porous Si-Ag particles to improve the conductivity of graphite and increase the efficiency of charge and discharge. The micro-nano porous Si-Ag powder !s prepared via chemical etching method, and ball mill 70% artificial graphite and 30% porous S-Ag powder to form a sandwiched composted structure. SEM,TEM,XRD and battery testing systems were used to characterize and test porous S-Ag powder material. According to the research results, the silicon parities have a of 720 nm after high-energy ball milling; under the etching conditions of 80, the obtained micro-nano porous S-Ag anode material has a charge discharge specific capacity of 2 163. 28 mAh/g;doped with porous S-The first charge and discharge specific cupidity of the graphite negative electrode after Ag particles can reach 1 227. 966 mAh/g, which !s 341. 1% higher than that of pure graphite anode material that a current density of 0. 2 C(1 C= 1 500 mA/g), The retention rate of the cupidity after 100 cycles is 59. 72%. [ABSTRACT FROM AUTHOR]

Objective To investigate the causes of the hemorrage during and after embolization of cerebral aneurysms. Methods and Results We retrospectively analyzed 153 patients who underwent embolization of cerebral aneurysms from January 2015 to April 2017. Raymond Classification following initial treatment indicated 91 cases (59.48%) were in Raymond grade I, 25 cases (16.34%) in Raymond grade II, 37 cases (24.18%) in Raymond grade III. Wide - necked aneurysms were seen in 73 cases (47.71%). Stent assisted embolization was done in 63 cases (41.18%). Intraoperative bleeding rate was 1.31% (2/153), causes of bleeding were rupture after repeated over-selection of coil micro-catheter in place (one case), rupture of aneurysm when release of the first coil after stent opening (one case) and the 2 cases all died. Postoperative rebleeding rate was 1.31% (2/153), both patients were Raymond grade III, one of them died after rebleeding, one with cerebral hematoma clearance and aneurysm clipping, the patient was followed up for one year in a stable condition. Conclusions Rupture of aneurysm wall by improper operation of micro-catheter or micro-guidewire during intracranial aneurysm embolization is the main cause of intraoperative bleeding, and Raymond Classification may be the influencing factor for rebleeding after embolization of cerebral aneurysms. [ABSTRACT FROM AUTHOR]

Green and efficient decontamination of nerve agent Vx has always been one of the difficulties and hot spots in military decontamination technology. Traditional chemical decontaminants have a good effect on Vx, but their problems of strong irritation to the skin, corrosion on the surface of contaminated equipment, large consumption, serious environmental pollution and toxic by-products remains. Therefore, it is necessary to develop the high activity, low corrosion, non-toxic by-products, and pollution-free decontaminants. As a natural degradation component, enzyme has a certain potential for the decontamination of chemical agents. This paper reviewed recent progress of phosphotriesterase with degradation activity to Vx, with the aim to provide an insight into the development of enzyme-based decontaminants. [ABSTRACT FROM AUTHOR]

Objective To explore the therapeutic effect and anti-inflammatory mechanism of selenium nanoparticles on rheumatoid arthritis rats. Methods Thirty rats were selected, 10 rats were fed normally without any intervention as the control group, and the other 20 healthy SD male rats were used to establish the rheumatoid arthritis models. The 19 successfully established rheumatoid arthritis rats were divided into the rheumatoid arthritis group of 10 cases and selenium nanoparticle group of 9 cases. The rats of the selenium nanoparticle group were given selenium nanoparticle solution, while the rats in the rheumatoid arthritis group were given normal saline. Foot volume measurement and arthritis index evaluation were performed in the two groups. The relative expression levels of serum glutathione peroxidase (GSH-Px) and cyclooxygenase-2 (COX-2) were detected by Western blotting and the interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by ELISA. Results On day 5, 10, 15, and 20, the rats in the rheumatoid arthritis group and selenium nanoparticle group had higher foot volume than the control group (P < 0.05). The rat foot volume of the selenium nanoparticle group was lower than that of the rheumatoid arthritis group (P < 0.05). On day 5, 10, 15 and 20, the rat arthritis indexes in the rheumatoid arthritis group was lower than that of selenium nanoparticle group (both P < 0.05). On the 5th, 10th, 15th and 20th days after modeling, the relative expression levels of IL-6 and TNF-α in rats of rheumatoid arthritis group and the selenium nanoparticles group were significantly higher than those of the control group (both P <0.05). On day 5, 10, 15 and 20, the relative expression levels of GSH-Px in the rheumatoid arthritis group and the selenium nanoparticles group were lower than those of the control group, but the relative expression levels of GSH-Px in the selenium nanoparticles group was higher than that in the rheumatoid arthritis group (all P < 0.05). On day 5, 10, 15 and 20, the relative expression of COX-2 in the rheumatoid arthritis group and selenium nanoparticles group was higher than that of the control group, which in the rheumatoid arthritis group was higher than that of the selenium nanoparticles group (all P <0.05). Conclusion Selenium nanoparticles can effectively decrease the severity of rheumatoid arthritis model rats and play an anti-inflammatory role by regulating the expression of serum GSH-Px and COX-2. [ABSTRACT FROM AUTHOR]

Glass fiber-reinforced PA6 composites were prepared by melt-blending with a twin-screw extruder, and the effects of humidity, water absorption, nucleating agent and heat treatment on their dimensional stability were investigated. The results indicated that the hygroscopic expansion and internal stress release shrinkage affected the size of the composites, and the former was the dominant factor. The higher the ambient humidity, the longer was the time. As a result, the bigger was the size of the composites. Moreover, its size variation in the vertical flow direction was greater than that in the flow direction. The lower the environmental humidity, the longer was the time required to achieve the same water absorption rate, resulting in a larger size of the composites. With an increase of the content of nucleating agent, the size of the composites tended to decrease slightly. The size variation achieved a minimum value at a content of nucleating agent of 0.5 phr. However, the size changed little with further increasing the content of nucleating agent. The heat treatment promoted the internal stress release shrinkage of the composites, resulting in a decrease of size variation rate of the composites due to an opposite effect by hygroscopic expansion. [ABSTRACT FROM AUTHOR]

[Introduction] The paper aims to sovle the sub-grade problems cause by complex karst and soil cave foundation, design problems in karst and soil cave foundation treatment design, construction problems often occurred in power plant projects, such as advanced drilling, bored pile and PHC pile construction difficult problems etc.. [Method] To describe the relevant karst and soil cave treatment key technologies, including treatment principles, treatment methods (including filling method, crossing method, pile foundation method), we analyzed and compared the relevant specifications, costs and practical engineering experience. [Results] The results we obtained is the solutions to the difficult problems in the treatment of karst and soil cavern foundation and the problems that are easy to occur in the punching construction of pile foundation of karst cavern foundation and the emergency response plan. [Conclusion] Finally, several treatment methods of karst foundation in power plant are suggesed, which can be used as reference for similar projects.

The injection molding liquid silicone rubber is prepared with polyaddition liquid silicone rubber as the base material and multi-vinyl silicone oil. The effects of the types and amounts of multi-vinyl silicone oil, the amounts of platinum catalyst and inhibitor on the vulcanization rate of the compounds were investigated. The results show that the more 10% multi-vinyl silicone oil with a viscosity of 5 000 mPa ⋅ s, the longer the positive vulcanization time of liquid silicone rubber; with the increase of the amounts of platinum catalyst, the positive vulcanization time of liquid silicone rubber is shortened; by using 8% multi-vinyl silicone oil with a viscosity of 15 000 mPa ⋅ s, the positive vulcanization time of liquid silicone rubber is shortened; when the inhibitor is reduced from 0.89 phr to 0.56 phr, the positive vulcanization time of liquid silicone rubber is shortened from 105 s to 89 s. [ABSTRACT FROM AUTHOR]

Objective To explore the feasibility of two-point Dixon water-at separation method in the assessment of marrow adiposity in estrogen-deficient rats. Methods Nineteen 12-week-old female Sprague-Dawley rats were randomly divided into sham-operated (SHAM, n = 9) and ovariectomized (OVX, n =9) group. Marrow fat fraction (FF) and bone mineral density (BMD) were measured at 0, 6, and 12 weeks. At the end of the experiment, marrow adipocytes were quantitatively evaluated. Results FF increased, but BMD decreased in OVX rats over time. FF increased in OVX group by 40. 0% at week 6 and by 69. 4% at week 12, respectively, compared to the baseline (P < 0. 001). Compared with SHAM rats, FF in OVX rats was markedly elevated at week 6 but a reduction in BMD first detected at week 12 (P <0. 001). The OVX rats had substantially higher adipocyte density (by 57. 3% ), size (by 29. 5% ), and volume (by 163% ) than SHAM rats. Conclusion OP is characterized by marrow adipogenesis as well as bone loss. Two-point Dixon water-fat separation may dynamically quantify marrow fat content. [ABSTRACT FROM AUTHOR]

Aiming at the problems that IGBT and its driver in the main circuit of the active power filter (APF) is easy to cause opencircuit fault, and how to use the virtual instrument technology to replace the traditional power quality analysis device for real-time monitoring on APF, through the analysis of the open-circuit fault of IGBT in APF, the hardware circuit on fault diagnosis was designed accordingly. At the same time, the hardware circuit monitoring the sampling signal of grid current and APF operating temperature was designed. The operatinging principle of circuit was analysised and defined. The real-time monitoring system based on LabVIEW was designed, the sampling data was sent to the monitoring system, and the real-time monitoring function of APF operation using host computer was achieved. Finally, the real-time sampling of the grid voltage and harmonic current signal, and the simulated test of opencircuit fault in IGBT were proceeded. The results indicate that the system can realize the real-time monitoring of the running state of APF, and can achieve the fault diagnosis function of IGBT and its driver, which has high accuracy and quick response. [ABSTRACT FROM AUTHOR]

An impeller blower mainly consists of throwing impeller, shell, discharge tube, etc. When the impeller blower is working, the material is transported by mechanical centrifugal force and airflow which are generated by a high-speed rotating impeller. As the core component of the impeller blower, the impeller have to bear the comprehensive effect of the centrifugal force, the pressure of high-speed air flow inside the impeller blower and impeller gravity, which may produce violent vibration. The vibration will not only accelerate the throwing blade's fatigue fracture and affect its service lifetime but also produce environmental noise. In the meantime, if the excitation frequency is closed to some-order natural frequency of the throwing impeller, the whole device would produce resonance which seriously affects the work performance, the service life and reliability of the impeller blower. Therefore, in order to improve the working performance of impeller blower and avoid the resonance, it is quite important to analyze the vibration characteristics of the throwing impeller. In this paper, the modal frequency and vibration types of the first 12-order free modal and constraint modal were calculated using the finite element analysis software ABAQUS. In order to verify the accuracy of numerical calculation, a modal test of the impeller was carried out using the PSV-500-3D Scanning Vibrometer, which showed the maximum error of numerical modal frequencies and experimental modal frequencies was 8.5%, the vibration types were basically the same, and the numerical calculation results were reliable. Based on analyzing the characteristics of external excitation frequency, the structural parameters such as blade number, blade thickness, whether reinforcement were simulated and compared. The results show that: 1) Prestress increased each order natural frequency of the impeller, and only the first and the second order frequency increased largely while other frequencies increased a little. Prestress has no impact on the vibration type of the impeller. 2) When the speed of impeller was 1 500 r/min, the deviation of excitation frequency and the first order natural frequency of the impeller with 3 blades was 57% and the resonance of impeller most unlikely took place. The deviation of excitation frequency and the first order natural frequency of the impeller with 4 blades was 15.9% and the resonance of impeller also couldn't take place. The excitation frequency deviated from the first order and second order natural frequency of the impeller with 5 blades by 13%, which most likely caused the resonance of impeller. 3) The lower natural frequencies of the impeller decreased and the higher natural frequencies increased with the blade thickness increasing. The natural frequency of the impeller with 4 mm thick blade deviated from the excitation frequency by 23% and the resonance of impeller most unlikely took place, while the natural frequency of the impeller with 5 mm thick blade deviated from the excitation frequency by 15.9% and the resonance of impeller also unlikely took place. But the impeller with 6 mm thick blade had low first order natural frequency and deviated from the high excitation frequency by 13%, which most likely caused the resonance of impeller. 4) The impeller with stiffeners could effectively avoid the vibration frequency, improve the dynamic performance and avoid the resonance. [ABSTRACT FROM AUTHOR]

Cervical cancer seriously threat the health of women, and human papillomavirus is closely related with cervical lesions and cervical cancer. People are striving to find the mechanism of the occurrence and development of cervical cancer. Recent years, studies indicate that a multi-functional nucleoprotein, death domain associated protein (Daxx) has been found. Daxx may interact with proteins in cells or viral proteins, and be involved in cell activities such as regulating cell apoptosis, transcription regulating or antiviral. It plays different roles in physiologically or pathologically through different pathways. Research the function and mechanism of Daxx can expand our knowledge of the origin and development mechanism of cervical cancer, which is helpful to find new methods of prevention and treatment. This paper reviews the biological characteristics and the current states of Daxx, and research progress on Daxx in cervical lesions. [ABSTRACT FROM AUTHOR]

The plastic wind tunnel has been widely used in China. At present, the reference wind pressure in the structural design of plastic tunnels is calculated by using the "Load code for the design of building structures". In fact, the plastic tunnel is a special form of construction which has a lighter structure; it uses a flexible covering material (such as plastic film) which is far less intensive than masonry, reinforced concrete structures, and even the light steel structures used in industrial and civil buildings. They are different in the degree of safety, importance, return period, the value of wind speed, height, and distance. The most adverse impact of the structure is extreme wind; it is possible for a gust to destroy the entire structure. Taking into consideration the lack of investment scale, structure importance, and the actual working life, it is unreasonable to use the industrial and civil buildings standards. For a long time, more and more experts have recommended the 3 sec extreme wind speed as the standard wind load design of greenhouses. Combined with the research into greenhouses at home and abroad, based on the characteristics of the plastic tunnel, the 3 sec extreme wind speed is used as the basis for calculating the reference wind pressure, which is calculated according to the recent 30 year 3 sec extreme wind speed data. Stations with over 10a extreme wind speed records were selected. On the assumption that the extreme wind speed should follow the extreme value type I probability distribution, once-in-a-decade wind speed was calculated, and the wind pressure value was entered into the formula, from which a basic wind pressure distribution map was created. The data shows that 3 sec extreme wind speed is between 19-50 m/sec and the basic wind pressure value is between 0.2-1.53 kN/m². The distribution map can reflect the basic wind pressure value in our country, lays the foundation for the structural design of the plastic tunnel, and provides a reference for the formulation of greenhouse load specification. In addition, the basic wind pressure value was calculated based on the 3 sec extreme wind speed. Both adopt to the structure design of greenhouse film strength design and frame skeleton. Moreover, the basic wind pressure is calculated by the date of which the standard height is 10 m, but the plastic tunnel height is between 4-5 m, so when calculating the plastic tunnel wind load, the basic wind pressure value referencing the load code for the design of building structures (GB50009-2012) should be reduced. [ABSTRACT FROM AUTHOR]

Aiming at the scheduling problem of flexible machining and assembly systems with reentrant subsystems, a negotiation framework was presented and a bargain-like bidirectional negotiation algorithm was developed in this paper. Multi-agents were adopted to construct the negotiation structure, which enable various agents have their own decision objectives. The objectives of job agents were to purchase appropriate services with low price, while the machine agents always try to sell their services with maximum profits. The global performance of scheduling solutions was improved since bidirectional negotiation provides a comprehensive decision rather than an independent local decision. Experimental results show that the standard deviation of total cost is 24% ~ 207% lower than various combinations of dispatching rules. Therefore, the proposed algorithm has better performance and robustness. [ABSTRACT FROM AUTHOR]

Objective To investigate the predictive value of the hip osteoporotic fractures from the hip structure analysis using dual energy X-ray absorptiometry (DXA). Methods Forty-one women with hip fractures (aging from 52. 3 to 89. 4 years old) and 259 health controls (aging from 28. 2 to 88. 3 years old) were selected. The femoral neck bone mineral density (FN_BMD) was detected using DXA. The geometry parameters of the proximal femur, including cross-sectional moment of inertia (CSMI), cross-sectional area (CSA), section modulus (SM), buckling ratio (BR), the femur neck width (FNW), the hip axis length (HAL), and the neck shaft angle (NSA) were also obtained. The femur strength index (FSI) was calculated. The predictive value of the correlated variables was analyzed using ROC curve areas (AUCs). Results After adjusting for the confounding factors, including age, height, weight, and BMI, the significant difference of FN_BMD between fracture group and non-fracture group was observed (P <0. 01). The hip structural parameters such as FSI, SM, CSMI, and CSA in the hip fracture group were lower than those in non-fracture group, while BR, FNW, NSA, and HAL were higher (P < 0. 05). After adjusting for FN_BMD, the remaining significant difference of FSI, NSA, and HAL was observed between the two groups (P < 0. 05). After controlling for the confounding factors, FN_BMD showed a low-moderate correlation with FSI (r = 0. 339), BR (r = - 0. 291), SM (r = 0. 644), CSMI (r = 0. 425), and NSA (r = - 0. 291), and the relationship between EN_BMD and CSA was the strongest (r = 0. 908, P < 0. 001). AUC for the hip fracture prediction from EN_BMD, FSI, HAL, and NSA was 0. 794 ± 0. 031, 0. 790 ± 0. 032, 0. 652 ± 0. 049, and 0. 684 ± 0. 049, respectively. FSI best predicted the risk for each fracture and did not differ significantly from FN_ BMD. AUC for FN_BMD combining with FSI was 0. 844 ± 0. 039, which was significantly higher than that of conventional FN_ BMD alone (P < 0. 05). Conclusion FSI, functioning independently from FN_BMD, may be valuable in the assessment of the hip osteoporotic fractures. A combination of FN_BMD and FSI is considered to have the potential to improve the value of risk assessment for the hip fractures. [ABSTRACT FROM AUTHOR]