OBJECTIVE: To evaluate the clinical efficacy and safety of Qiguiyin(QGY) formula in patients with severe pneumonia in China compared with a placebo.METHODS: This is a multicenter double-blind, placebo-controlled, rand...OBJECTIVE: To evaluate the clinical efficacy and safety of Qiguiyin(QGY) formula in patients with severe pneumonia in China compared with a placebo.METHODS: This is a multicenter double-blind, placebo-controlled, randomized clinical trial with two parallel arms. There will be 530 patients enrolled and randomized into either the experimental group(QGY formula) or the control group(placebo). Therapies for patients in the two groups above will be based on the conventional therapy. The primary outcome is 28-day mortality. Secondary outcomes include:(a) duration of hospital stay;(b) duration of time in the intensive care unit(ICU) stays;(c) duration of mechanical ventilation;(d) antibiotic DDD value(which means the doses of antibotics during the treatment period);(e) serum procalcitonin(PCT) level;(f) serum C-reactive protein(CRP)level;(g) Pneumonia severity index(PSI) score;(h)Sequential Organ Failure Assessment(SOFA) score;(i) sputum culture results;(j) blood routine examination results;(k) routine urine test results;(l) stool routine examination results;(m) electrocardiogram results;(n) alanine aminotransferase levels;(o) aspartate amino transferase levels;(p) total bilirubin;(q) creatinine levels;(r) urea nitrogen levels;and(s)adverse events.ETHICS AND DISSEMINATION: The protocol has been approved by the Research Ethics Committee of Beijing Hospital of Traditional Chinese Medicine,Affiliated with Capital Medical University(2018 BL-053-02). This trial aims to provide evidence for QGY formula combined with conventional therapy in treating patients with severe bacterial pneumonia,and to verify the clinical effectiveness and safety of QGY formula in China compared with placebo. Additionally, this trial will reveal the effect of QGY formula on delaying/reversing the characteristics of drug-resistant bacteria.Trial registration number: Chi CTR1800019785.展开更多
The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this p...The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to 2015.The results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend;2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the west.According to the evolution track of the system’s vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into ‘declining’ and ‘stable’ types of evolutionary structures;3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery’s ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery’s science and technology talents, etc.Then, the marine fishery’s development in the Bohai Rim Region will be moving in the green, circular and sustainable direction.展开更多
Borehole leakage not only affects the gas drainage effect but also presents considerable risk to human security. For the research on the leakage mechanism of gas drainage borehole, the rheological and visco-elastic-pl...Borehole leakage not only affects the gas drainage effect but also presents considerable risk to human security. For the research on the leakage mechanism of gas drainage borehole, the rheological and visco-elastic-plastic characteristics were considered to establish the mechanical model of coal mass around borehole, which is used to analyze the leakage mechanism and deduce the dynamic leakage model. On the basis of the real coal seam conditions, the variation rules of the stress, leakage ring, and air leakage amount were analyzed through numerical simulation, and the influence factors of air leakage amount were also investigated to provide the theoretical basis for the sealing technology. Results show that the air leakage amount of borehole is inversely proportional to the increase in supporting stress and sealing length, and directly correlated with the increase in borehole radius and softening modulus. Using theoretical analysis, we design a novel active supporting sealing technology that can use grouting material to seal the fractures to reduce the leakage channels and also provide supporting stress to prevent borehole deformation. The engineering test results indicate that the average gas concentration with the novel active supporting sealing technology is increased by 162.12% than that of traditional polyurethane sealing method. Therefore, this technology not only effectively resolves borehole leakage but also significantly improves the gas drainage effect.展开更多
Electro-hydraulic control systems are nonlinear in nature and their mathematic models have unknown parameters. Existing research of modeling and identification of the electro-hydraulic control system is mainly based o...Electro-hydraulic control systems are nonlinear in nature and their mathematic models have unknown parameters. Existing research of modeling and identification of the electro-hydraulic control system is mainly based on theoretical state space model, and the parameters identification is hard due to its demand on internal states measurement. Moreover, there are also some hard-to-model nonlinearities in theoretical model, which needs to be overcome. Modeling and identification of the electro-hydraulic control system of an excavator arm based on block-oriented nonlinear（BONL） models is investigated. The nonlinear state space model of the system is built first, and field tests are carried out to reveal the nonlinear characteristics of the system. Based on the physic insight into the system, three BONL models are adopted to describe the highly nonlinear system. The Hammerstein model is composed of a two-segment polynomial nonlinearity followed by a linear dynamic subsystem. The Hammerstein-Wiener（H-W） model is represented by the Hammerstein model in cascade with another single polynomial nonlinearity. A novel Pseudo-Hammerstein-Wiener（P-H-W） model is developed by replacing the single polynomial of the H-W model by a non-smooth backlash function. The key term separation principle is applied to simplify the BONL models into linear-in-parameters struc^tres. Then, a modified recursive least square algorithm（MRLSA） with iterative estimation of internal variables is developed to identify the all the parameters simultaneously. The identification results demonstrate that the BONL models with two-segment polynomial nonlinearities are able to capture the system behavior, and the P-H-W model has the best prediction accuracy. Comparison experiments show that the velocity prediction error of the P-H-W model is reduced by 14%, 30% and 75% to the H-W model, Hammerstein model, and extended auto-regressive （ARX） model, respectively. This research is helpful in controller design, system monitoring and diagnosis.展开更多
A new 3D complex,[Co（L）（bpe）0.5（H2O）2]n（1,H2 L = 5-iodo-benzene-1,3-dioxyacetic acid,bpe = 1,2-bis（4-pyridyl）ethylene）,has been hydrothermally synthesized and structurally characterized by elemental analysis...A new 3D complex,[Co（L）（bpe）0.5（H2O）2]n（1,H2 L = 5-iodo-benzene-1,3-dioxyacetic acid,bpe = 1,2-bis（4-pyridyl）ethylene）,has been hydrothermally synthesized and structurally characterized by elemental analysis,IR and X-ray diffraction.It is formulated as C16H16 Co INO8,crystallizes in monoclinic,space group P21/c,with a = 9.806（2）,b = 6.5492（13）,c = 28.187（8） A,β = 100.12（3）°,V = 1782.0（7） A^3,Z = 4,Dc = 1.998 g/m^3,F（000） = 1052,Μr = 536.13,the final R = 0.0393 and w R = 0.0858 for 3134 observed reflections with I 〉 2σ（I）.Complex 1 displays a 3D framework with multiform helical features,left-and right-handed triple helical braids and single helical chains,which can be simplified as a new type of（3,4）-connected lattice with a（6·10^2）（6^2·10^4） SchlAfli symbol.Moreover,the thermal analysis of complex 1 has also been investigated.展开更多
The approaches adopted so far in China to calculate reserves of ore deposits have largely been dependent on polygonal methods, including a cross-section method and a geological block method. However, for various reaso...The approaches adopted so far in China to calculate reserves of ore deposits have largely been dependent on polygonal methods, including a cross-section method and a geological block method. However, for various reasons, especially, the complexity of the geology, and the ore bodies, the deposits became gradually known as development and exploitation took place. There is a certain difference between the prospecting and mining, which will have a great impact on both geological and cutoff grade at the stage of geological mine construction and production. As much accurate information as possible on the spatial distribution patterns of ore bodies and global reserves is essential to improve the production efficiency and reduce production cost. The 10-9 ore body of Lutangba in the Gejiu Tin Deposits was selected as our research object, using a log Kriging and an inverse distance weighing method. In our paper the results are compared with the reserves calculated by the polygonal block method. The global estimate and estimation errors associated with each estimation method are discussed.展开更多
多频高精度定位中需要考虑新频率对定位性能的影响。传统相位频间钟偏差(inter frequency clock bias,IFCB)处理方法受制于参考站数量,且与接收机和卫星相关的硬件延迟相关,影响多频精密单点定位(precision point positioning,PPP)的可...多频高精度定位中需要考虑新频率对定位性能的影响。传统相位频间钟偏差(inter frequency clock bias,IFCB)处理方法受制于参考站数量,且与接收机和卫星相关的硬件延迟相关,影响多频精密单点定位(precision point positioning,PPP)的可靠性和准确性。针对IFCB对多全球导航卫星系统(global navigation satellite system,GNSS)多频PPP的影响,本文提出了基于测站IFCB观测值提取功率谱密度(power spectral density,PSD)的算法,进一步构建IFCB参数时变特性约束的多频PPP算法,并全面分析了IFCB的时变特性和不同IFCB模型对非差非组合PPP性能的影响。试验结果表明:依据测站IFCB观测值提取IFCB功率谱密度可行且有效。相较于忽略IFCB方法,采用PSD约束的随机模型估计IFCB,PPP在收敛时间提升最大,提升46.51%,采用iGMAS产品和CNES产品平均提升43.54%、34.50%,三维定位精度分别提升41.68%、32.24%、24.64%。并且,将IFCB采用时变特性约束的随机模型参数优化方案能真实地反映IFCB变化。因此,在多GNSS多频PPP处理中,将IFCB参数采用时变特性约束的随机模型参数优化方案能够加快位置收敛速度,提升定位精度,优于产品改正方法,更有利于实时多频PPP的应用。展开更多
This paper presented the application of the direct hot charge rolling （DHCR） technology in Ningbo Steel. Five aspects have been systematically addressed and analyzed, which include sales order, production schedule p...This paper presented the application of the direct hot charge rolling （DHCR） technology in Ningbo Steel. Five aspects have been systematically addressed and analyzed, which include sales order, production schedule programming, steelmaking,continuous casting and hot-rolling. The average DHCR product rate has reached 55% and the average slab charging temperature 699℃. As a result, the production cost, the energy consumption and the CO2emission have been significantly reduced. It is concluded that a breakthrough in application of the DHCR technology has been achieved at Ningbo Steel.展开更多
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the...Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.展开更多
Thermal deformation characteristics of Fe-Cr-Ni-based alloys for nuclear power plants were investigated using a Gleeble3500 thermal simulation tester.The microstructure evolution law of alloy heat deformation was inve...Thermal deformation characteristics of Fe-Cr-Ni-based alloys for nuclear power plants were investigated using a Gleeble3500 thermal simulation tester.The microstructure evolution law of alloy heat deformation was investigated using the electron backscatter diffraction(EBSD)technique.Results demonstrate that the flow stress curves show typical dynamic recrystallization(DRX)characteristics.According to EBSD analysis,the nucleation and growth of DRX grains are mainly at grain boundaries.The complete DRX occurs at 1100℃/0.01 s^(−1) condition,and the grains are refined.The main DRX nucleation mechanism of the alloy is the grain boundary bowing nucleation.Therefore,the softening mechanism of Fe-Cr-Ni-based alloys for nuclear power plants is the combination of dynamic recovery and DRX.The Arrhenius constitutive model with strain compensation is developed.The correlation coefficient between the predicted and experimental values is 0.9947.The reliable mathematical model of critical stress(strain)and Z parameter is obtained.The critical stress(strain)of DRX increases as the temperature decreases or the strain rate increases.The DRX kinetic model is established by the Avrami model,and a typical S-type curve is obtained.As the strain rate decreases and the temperature increases,the volume fraction of DRX increases.展开更多
以Li H2PO4、Fe2O3及葡萄糖为原材料,采用高温高能球磨法(HTHEBM)制备了性能优良的碳包覆磷酸铁锂(Li Fe PO4/C)正极材料。在该法中,高能球磨将机械能转变为热能,有效降低了烧结温度且减少了烧结时间,在600℃下9 h烧结后获得纯相的Li Fe...以Li H2PO4、Fe2O3及葡萄糖为原材料,采用高温高能球磨法(HTHEBM)制备了性能优良的碳包覆磷酸铁锂(Li Fe PO4/C)正极材料。在该法中,高能球磨将机械能转变为热能,有效降低了烧结温度且减少了烧结时间,在600℃下9 h烧结后获得纯相的Li Fe PO4/C正极材料。利用X射线衍射、扫描电镜、透射电镜、电化学性能测试等方法研究产物的结构、形貌及电化学性能。结果表明:所得Li Fe PO4/C材料为类球型橄榄石型结构,平均粒径为0.5μm;在0.1 C充放电倍率下,首次放电比容量为152.5 mAh·g-1;不同充放电倍率下,60次循环后放电比容量基本不变。与传统高温固相法及高温球磨法在相同条件下所制备的磷酸铁锂正极材料相比,本方法所得Li Fe PO4/C材料的性能明显较优。展开更多
The Chinese seabass(Lateolabrax maculatus)is one of the most popular and valuable aquaculture species in China.Recently,the disease caused by Vibrio anguillarum has brought huge economic losses in the L.maculatus indu...The Chinese seabass(Lateolabrax maculatus)is one of the most popular and valuable aquaculture species in China.Recently,the disease caused by Vibrio anguillarum has brought huge economic losses in the L.maculatus industry.However,the immune response of L.maculatus after V.anguillarum infection remains unknown.In this study,the blood homeostasis,gut microbiota and transcriptomic profiling of L.maculatus after V.anguillarum infection were investigated.Our results indicated that the levels of superoxide dismutase(SOD),alanine aminotransferase(ALT)and total bilirubin(TBIL)increased,while the levels of blood glucose(BG),total protein(TP)and albumin(ALB)decreased after V.anguillarum infection.The analysis of the gut microbiota composition revealed that the dominant phyla was Firmicutes and Proteobacteria,and the relative abundance of genus Vibrio increased after V.anguillarum infection.Subsequently,the differentially expressed genes(DEGs)in the kidney and spleen after V.anguillarum infection were analyzed by transcriptome sequencing.The results indicated that immunity-related genes like TLR5,TLR8,TLR9,IL-1β,CCL3,IFNγ,CXCL11 and TNFαwere affected and the NOD-like receptor signaling pathway,cytokine-cytokine receptor interaction and Toll-like receptor signaling were activated.Thus,an effective immune and pro-flammatory response can help resist V.anguillarum infection.Our results provide a theoretical support for improving the disease resistance ability of L.maculatus.展开更多
基金Supported by Capital Health Development Project:The efficacy and Bacterial Resistance of Qiguiyin Formula in the Treatment of Severe Bacterial Pneumonia(SF-2018-1-1161)Protocol Version:(3.0,Nov-13-2018)。
文摘OBJECTIVE: To evaluate the clinical efficacy and safety of Qiguiyin(QGY) formula in patients with severe pneumonia in China compared with a placebo.METHODS: This is a multicenter double-blind, placebo-controlled, randomized clinical trial with two parallel arms. There will be 530 patients enrolled and randomized into either the experimental group(QGY formula) or the control group(placebo). Therapies for patients in the two groups above will be based on the conventional therapy. The primary outcome is 28-day mortality. Secondary outcomes include:(a) duration of hospital stay;(b) duration of time in the intensive care unit(ICU) stays;(c) duration of mechanical ventilation;(d) antibiotic DDD value(which means the doses of antibotics during the treatment period);(e) serum procalcitonin(PCT) level;(f) serum C-reactive protein(CRP)level;(g) Pneumonia severity index(PSI) score;(h)Sequential Organ Failure Assessment(SOFA) score;(i) sputum culture results;(j) blood routine examination results;(k) routine urine test results;(l) stool routine examination results;(m) electrocardiogram results;(n) alanine aminotransferase levels;(o) aspartate amino transferase levels;(p) total bilirubin;(q) creatinine levels;(r) urea nitrogen levels;and(s)adverse events.ETHICS AND DISSEMINATION: The protocol has been approved by the Research Ethics Committee of Beijing Hospital of Traditional Chinese Medicine,Affiliated with Capital Medical University(2018 BL-053-02). This trial aims to provide evidence for QGY formula combined with conventional therapy in treating patients with severe bacterial pneumonia,and to verify the clinical effectiveness and safety of QGY formula in China compared with placebo. Additionally, this trial will reveal the effect of QGY formula on delaying/reversing the characteristics of drug-resistant bacteria.Trial registration number: Chi CTR1800019785.
基金Under the auspices of the National Natural Science Foundation of China(No.41201114,41976207)Finance Department of Liaoning Province(No.18C021)
文摘The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to 2015.The results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend;2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the west.According to the evolution track of the system’s vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into ‘declining’ and ‘stable’ types of evolutionary structures;3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery’s ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery’s science and technology talents, etc.Then, the marine fishery’s development in the Bohai Rim Region will be moving in the green, circular and sustainable direction.
基金supported by the National Natural Science Foundation of Youth Science Fund Project of China (No. 51604096)Funded by Hebei State Key Laboratory of Mine Disaster Prevention of China (No. KJZH2017K08)+1 种基金Funded by the Research Fund of State and Local Joint Engineering Laboratory for Gas Drainage & Ground Control of Deep Mines (Henan Polytechnic University) of China (No. G201609)He Nan Research Program of Application Foundation and Advanced Technology of China (No. 162300410031)
文摘Borehole leakage not only affects the gas drainage effect but also presents considerable risk to human security. For the research on the leakage mechanism of gas drainage borehole, the rheological and visco-elastic-plastic characteristics were considered to establish the mechanical model of coal mass around borehole, which is used to analyze the leakage mechanism and deduce the dynamic leakage model. On the basis of the real coal seam conditions, the variation rules of the stress, leakage ring, and air leakage amount were analyzed through numerical simulation, and the influence factors of air leakage amount were also investigated to provide the theoretical basis for the sealing technology. Results show that the air leakage amount of borehole is inversely proportional to the increase in supporting stress and sealing length, and directly correlated with the increase in borehole radius and softening modulus. Using theoretical analysis, we design a novel active supporting sealing technology that can use grouting material to seal the fractures to reduce the leakage channels and also provide supporting stress to prevent borehole deformation. The engineering test results indicate that the average gas concentration with the novel active supporting sealing technology is increased by 162.12% than that of traditional polyurethane sealing method. Therefore, this technology not only effectively resolves borehole leakage but also significantly improves the gas drainage effect.
基金supported by National Natural Science Foundation of China(Grant No.51175511)
文摘Electro-hydraulic control systems are nonlinear in nature and their mathematic models have unknown parameters. Existing research of modeling and identification of the electro-hydraulic control system is mainly based on theoretical state space model, and the parameters identification is hard due to its demand on internal states measurement. Moreover, there are also some hard-to-model nonlinearities in theoretical model, which needs to be overcome. Modeling and identification of the electro-hydraulic control system of an excavator arm based on block-oriented nonlinear（BONL） models is investigated. The nonlinear state space model of the system is built first, and field tests are carried out to reveal the nonlinear characteristics of the system. Based on the physic insight into the system, three BONL models are adopted to describe the highly nonlinear system. The Hammerstein model is composed of a two-segment polynomial nonlinearity followed by a linear dynamic subsystem. The Hammerstein-Wiener（H-W） model is represented by the Hammerstein model in cascade with another single polynomial nonlinearity. A novel Pseudo-Hammerstein-Wiener（P-H-W） model is developed by replacing the single polynomial of the H-W model by a non-smooth backlash function. The key term separation principle is applied to simplify the BONL models into linear-in-parameters struc^tres. Then, a modified recursive least square algorithm（MRLSA） with iterative estimation of internal variables is developed to identify the all the parameters simultaneously. The identification results demonstrate that the BONL models with two-segment polynomial nonlinearities are able to capture the system behavior, and the P-H-W model has the best prediction accuracy. Comparison experiments show that the velocity prediction error of the P-H-W model is reduced by 14%, 30% and 75% to the H-W model, Hammerstein model, and extended auto-regressive （ARX） model, respectively. This research is helpful in controller design, system monitoring and diagnosis.
基金the financial support by the Science and Technology Research Key Project Department of Education in Henan Province(14A150026)Nanyang Normal University Scientific Research Foundation Project(ZX2014041)
文摘A new 3D complex,[Co（L）（bpe）0.5（H2O）2]n（1,H2 L = 5-iodo-benzene-1,3-dioxyacetic acid,bpe = 1,2-bis（4-pyridyl）ethylene）,has been hydrothermally synthesized and structurally characterized by elemental analysis,IR and X-ray diffraction.It is formulated as C16H16 Co INO8,crystallizes in monoclinic,space group P21/c,with a = 9.806（2）,b = 6.5492（13）,c = 28.187（8） A,β = 100.12（3）°,V = 1782.0（7） A^3,Z = 4,Dc = 1.998 g/m^3,F（000） = 1052,Μr = 536.13,the final R = 0.0393 and w R = 0.0858 for 3134 observed reflections with I 〉 2σ（I）.Complex 1 displays a 3D framework with multiform helical features,left-and right-handed triple helical braids and single helical chains,which can be simplified as a new type of（3,4）-connected lattice with a（6·10^2）（6^2·10^4） SchlAfli symbol.Moreover,the thermal analysis of complex 1 has also been investigated.
文摘The approaches adopted so far in China to calculate reserves of ore deposits have largely been dependent on polygonal methods, including a cross-section method and a geological block method. However, for various reasons, especially, the complexity of the geology, and the ore bodies, the deposits became gradually known as development and exploitation took place. There is a certain difference between the prospecting and mining, which will have a great impact on both geological and cutoff grade at the stage of geological mine construction and production. As much accurate information as possible on the spatial distribution patterns of ore bodies and global reserves is essential to improve the production efficiency and reduce production cost. The 10-9 ore body of Lutangba in the Gejiu Tin Deposits was selected as our research object, using a log Kriging and an inverse distance weighing method. In our paper the results are compared with the reserves calculated by the polygonal block method. The global estimate and estimation errors associated with each estimation method are discussed.
文摘This paper presented the application of the direct hot charge rolling （DHCR） technology in Ningbo Steel. Five aspects have been systematically addressed and analyzed, which include sales order, production schedule programming, steelmaking,continuous casting and hot-rolling. The average DHCR product rate has reached 55% and the average slab charging temperature 699℃. As a result, the production cost, the energy consumption and the CO2emission have been significantly reduced. It is concluded that a breakthrough in application of the DHCR technology has been achieved at Ningbo Steel.
文摘Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.
基金Key Projects of Hubei Provincial Department of Education(D20201206)Industrial Technology Basic Public Service Platform in 2022(2022-232-223)National Natural Science Foundation of China(51531009)。
文摘Thermal deformation characteristics of Fe-Cr-Ni-based alloys for nuclear power plants were investigated using a Gleeble3500 thermal simulation tester.The microstructure evolution law of alloy heat deformation was investigated using the electron backscatter diffraction(EBSD)technique.Results demonstrate that the flow stress curves show typical dynamic recrystallization(DRX)characteristics.According to EBSD analysis,the nucleation and growth of DRX grains are mainly at grain boundaries.The complete DRX occurs at 1100℃/0.01 s^(−1) condition,and the grains are refined.The main DRX nucleation mechanism of the alloy is the grain boundary bowing nucleation.Therefore,the softening mechanism of Fe-Cr-Ni-based alloys for nuclear power plants is the combination of dynamic recovery and DRX.The Arrhenius constitutive model with strain compensation is developed.The correlation coefficient between the predicted and experimental values is 0.9947.The reliable mathematical model of critical stress(strain)and Z parameter is obtained.The critical stress(strain)of DRX increases as the temperature decreases or the strain rate increases.The DRX kinetic model is established by the Avrami model,and a typical S-type curve is obtained.As the strain rate decreases and the temperature increases,the volume fraction of DRX increases.
文摘以Li H2PO4、Fe2O3及葡萄糖为原材料,采用高温高能球磨法(HTHEBM)制备了性能优良的碳包覆磷酸铁锂(Li Fe PO4/C)正极材料。在该法中,高能球磨将机械能转变为热能,有效降低了烧结温度且减少了烧结时间,在600℃下9 h烧结后获得纯相的Li Fe PO4/C正极材料。利用X射线衍射、扫描电镜、透射电镜、电化学性能测试等方法研究产物的结构、形貌及电化学性能。结果表明:所得Li Fe PO4/C材料为类球型橄榄石型结构,平均粒径为0.5μm;在0.1 C充放电倍率下,首次放电比容量为152.5 mAh·g-1;不同充放电倍率下,60次循环后放电比容量基本不变。与传统高温固相法及高温球磨法在相同条件下所制备的磷酸铁锂正极材料相比,本方法所得Li Fe PO4/C材料的性能明显较优。
基金received funding from the Natural Science Foundation of Shandong Province(No.ZR2023MC141)the Innovation and Entrepreneurship Training Program for College Students(No.202210435003)financial support was also provided by the‘First Class Fishery Discipline’Program and the Special Talent Program‘One Thing One Decision(Yishi Yiyi)’in Shandong Province,China。
文摘The Chinese seabass(Lateolabrax maculatus)is one of the most popular and valuable aquaculture species in China.Recently,the disease caused by Vibrio anguillarum has brought huge economic losses in the L.maculatus industry.However,the immune response of L.maculatus after V.anguillarum infection remains unknown.In this study,the blood homeostasis,gut microbiota and transcriptomic profiling of L.maculatus after V.anguillarum infection were investigated.Our results indicated that the levels of superoxide dismutase(SOD),alanine aminotransferase(ALT)and total bilirubin(TBIL)increased,while the levels of blood glucose(BG),total protein(TP)and albumin(ALB)decreased after V.anguillarum infection.The analysis of the gut microbiota composition revealed that the dominant phyla was Firmicutes and Proteobacteria,and the relative abundance of genus Vibrio increased after V.anguillarum infection.Subsequently,the differentially expressed genes(DEGs)in the kidney and spleen after V.anguillarum infection were analyzed by transcriptome sequencing.The results indicated that immunity-related genes like TLR5,TLR8,TLR9,IL-1β,CCL3,IFNγ,CXCL11 and TNFαwere affected and the NOD-like receptor signaling pathway,cytokine-cytokine receptor interaction and Toll-like receptor signaling were activated.Thus,an effective immune and pro-flammatory response can help resist V.anguillarum infection.Our results provide a theoretical support for improving the disease resistance ability of L.maculatus.
