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To deal with the notorious shuttle behavior and sluggish conversion of lithium polysulfides (LiPSs), heteroatoms doping and defects creating are practical strategies for improving capture and catalytic conversion of LiPSs. In this work, O doped porous carbon materials (OPC) with a 3D hierarchical structure, consisting of 2–4 μm carbon sheets decorated with macrospores of 0.2–0.4 μm, was fabricated with MgO template. It is found that the increasing the carbonization temperature and the amount of MgO will make OPC rich in oxygen functional groups and defect sites. Electrochemical measures show that the OPC12–800 achieves reversible capacity (an initial discharge specific capacity of 1448.4 mAh g−1 at current density of 0.1 C) and cycling performance (717.7 mAh g−1 at 2 C over 200 cycles). The excellent electrochemical performance is attributed to the hierarchical porous structure, abundant C–O/C=O and defects, which effectively adsorbs polysulfides and promote faster redox reaction of LiPSs. This study provides an alternative to improve the performance of carbon materials as host of Li–S batteries by regulating the types of oxygen-containing functional groups and defects on carbon surface.

ZrO2-5CrMnMo composites were fabricated by ceramic injection molding in this research. The hardness and wear properties of ZrO2 ceramic layer and 5CrMnMo substrate were investigated. Moreover, physical properties and microstructures of ZrO2 ceramic coatings were studied and the interfaces of composite samples were observed. The results illustrated that the interface was smooth and properly bonded, and it was concluded that the 5CrMnMo substrate ceramic layer could be provided effectively by ZrO2 ceramic coating. Thermal insulation and thermal shock cycle tests were carried out. The heat insulating property of ZrO2 ceramic coating was remarkable, and even better at a high temperature. The composite samples prepared at 1200 °C did not failed until after more than 68 thermal shocks. The main reasons of limiting the application of this composites so far were still the physical and thermodynamic mismatch between ceramics and steel. But the composite samples fabricated by ceramic injection molding showed excellent thermal shock resistance and high bonding strength in this work.

Background Marfan syndrome (MFS) is a rare autosomal dominant connective tissue disorder. Diagnosing MFS can be challenging as the disease's severity and clinical manifestations differ between pathogenic variants, and because a lack of published information currently exists on phenotype-genotype correlations. This report aims to underline the clinical manifestations associated with fibrillin-1 (FBN1) gene mutations by assessing MFS in 6 families from China. Methods We diagnosed 6 patients and their relatives with MFS by combining a clinical examination (based on the 2010 revised Ghent nosology criteria) with a targeted next-generation sequencing analysis. The functional analysis of the causal mutations and clinical details of the affected patients were then assessed. Results We identified 6 pathogenic mutations in FBN1, including 1 novel frameshift, 1 nonsense, and 4 missense mutations. Most uniquely, mitral valve prolapses (MVP) and ectopia lentis (EL) were found in the cysteine-related mutations. Typically, facial symptoms of MFS are observed in frameshift or nonsense mutants, not in cysteine-related ones. Furthermore, the patients with premature terminal codons had a more serious skin condition than patients with missense mutations, partly indicating the important effect FBN1 has on skin. Conclusions This study expands the mutation spectrum of MFS and highlights possible genotype-phenotype correlations, thereby improving the early diagnosis and symptomatic treatment of the disease.

ZrO2-5CrMnMo composite samples were prepared by hot press sintering. When NiCoCrAlY powders were used as the bonding layer and the different mixtures of NiCoCrAlY alloy and 3YSZ (3mol% yttria stabilized zirconia) ceramic powders were used as the transition layers, the connection between zirconia ceramic and 5CrMnMo steel were strengthened. Three composite samples with different structures were fabricated by heat spraying and hot press sintering. Shear and thermal shock cycle tests were conducted to characterize connection strength and thermal shock resistance of these samples. The shear strength reached 95.69 MPa, and the heating shock cycles achieved to the maximum value of 27.7 times. Microstructures and connection interfaces were analyzed by scanning electron microscopy. The hardness and wearing resistance of 3YSZ coat and 5CrMnMo substrate were compared, and the heat insulation property of composite samples were also discussed. It is shown that these composite materials fabricated in this research are benefited to be used as squeeze casting dies.

Composite mold samples used in squeeze casting was fabricated by plasma spraying with 5CrMnMo and 3YSZ, which was shown high bonding strength and good thermal shock resistance. The best parameters with transition coat were explored by mechanical analyses. As results, the transition layer structure made of 75 percent NiCoCrAlY powders showed bonding strength was higher to 34.35MPa and that thermal cycles were up to 46.8 times. The effect of the transition layer was analyzed by microstructures and the failure mechanism of the coating material with a transition layer was discussed. The conclusion was that the physical mismatch and thermodynamic mismatch between the matrix and ceramic layers were the main cause of the failure.

The development of novel cermet composites based on porous ceramics with high porosity, interconnected pore structure and good mechanical property has attracted considerable attention in engineering application. In this work, water-based freeze casting process was employed to fabricate ZrB2-SiC porous ceramic with aligned lamellar-channels structure using PAA-NH4 as the dispersant. The results revealed that the well-dispersed suspension with best rheological behavior was obtained using 1.0 wt% PAA-NH4 at pH 9. The crack-free porous ceramic exhibited small volume shrinkage ranging from 2.59 % to 1.87 %. By varying the solid loading, the fabricated samples displayed a tailored porosity ranging from 76.12% to 59.37% and an excellent compressive strength of 7 MPa to 78 MPa. After oxidation, the samples displayed a decreased porosity and an increased compressive strength. The ZrB2­SiC porous ceramic fabricated in this work will be a promising candidate for the framework of cermet composite.

The research on the ceramic/metal composites with interpenetrating continuous lamellar structure has attracted much interest in structural materials field. In this work, we proposed an innovative approach to fabricate co-continuous ZrB2–SiC/Zn–5Al composites by combining freeze casting with ultrasonic-assisted spontaneous infiltration. The ZrB2–SiC porous ceramic with orderly lamellar channels (30 vol%) was fabricated by freeze casting using ammonium polyacrylate as the dispersant. The effects of ultrasonication duration on the microstructure and mechanical properties of the composites were investigated in detail. Results indicated that the ultrasonication improved the wettability and facilitated the spontaneous infiltration. The composites obtained the excellent comprehensive properties when the duration was 300 s, which can be attributed to not only the sufficient infiltration of lamellar channels but also the longer infiltration distance inside the ceramic walls induced by the ultrasonic capillary and cavitation.

Background. Thoracic aortic aneurysm or dissection (TAAD) is a group of life-threatening diseases. Genetic etiology lead to some special characteristics on age of onset, clinical phenotype, and timing of intervention. Herein, we initiated a prospective trial to determine the prevalence of pathogenic variants in TAAD patients and to elucidate the traits related to harboring pathogenic variants. One hundred and one unrelated TAAD patients were sequenced and analyzed for 23 TAAD associated genes using a targeted PCR and next generation sequencing-based panel. Results. A total of 47 variants were identified in 52 TAAD patients (51.5%) including 6 pathogenic, 1 likely pathogenic and 40 variants of uncertain significance. The pathogenic or likely pathogenic (P/LP) variants in 4 disease-causing genes were carried by 1 familial and 6 sporadic cases (6.9%). Besides one familial TAAD, the FBN1 gene also harbored more than half of the P/LP variants in sporadic ones. The individuals with the age of onset less than 50 years and normotension massively increased the genetic risk. Conclusions. The TAAD cases with younger age at diagnosis and normotension were more likely to carry a P/LP variant, thus routine genetic testing will be beneficial to better prognosis through a genetically personalized care prior to acute rupture or dissection.

In this paper, 45# steel supports prepared by liquid forging showed excellent performances and the effects of processing techniques on the development of microstructures and mechanical properties of these steel supports were researched. The liquid forging process was simulated and technological parameters were optimized via a ProCAST simulation software. The solidification time, temperature distribution, first principal stress distribution of the 45# steel supports varied with time, temperatures, and position. Two principal parameters, pouring temperature and dwell time, were assessed for their effects on microstructures, mechanical properties, and wear resistance properties of 45# steel supports. Results showed that the optimal pouring temperature of the molten metal and the pressure-holding time were between 1540 °C and 1560 °C and between 35 s and 40 s, respectively. The microstructure, mechanical properties, and fracture behavior of different positions in the support were also discussed, and the central position performed better than the edge because of plastic deformation. Finally, the dynamic solidification process was also investigated and the liquid forging process of 45# steel supports was complex and contained some special metal liquid convection and several plastic deformation stages.

Herein, warm drawing technology assisted by an electric current heating system is proposed to minimize the formation of wrinkles and cracks on the surface of Q390A high-strength steel V-shaped stiffeners during cold forming. V-shaped stiffeners with excellent properties were obtained by elevating the forming temperature and improving the material plasticity. The influence of temperature and tensile rate on the mechanical properties of the Q390A high-strength steel at 400-800°C was investigated. The effects of blankholder force and friction coefficient on the formed parts were simulated and analyzed by the finite element simulation software DYNAFORM. The law of heating and cooling for the formed parts during the forming process was studied through the electric current heating experiments. The forming temperature was controlled from 530 to 720 °C as the current density was maintained in the range from 7.3 to 8.5 A/mm2. Surface oxidation, cracks, sheet warping degree, sectional thickness distribution, mechanical properties, and microstructure of the V-shaped stiffeners formed at 400 to 700 °C were analyzed. The results show that the V-shaped stiffeners formed at 600 °C possess excellent overall properties.

In order to significantly enhance the performance of graphene in metal matrix composites, in situ SiC nanorods were successfully fabricated to enhance graphene nanoplatelets (GNPs)-reinforced Al2024 composite, which was prepared by powder semi-solid processing and friction stir processing. The SiC–GNPs dispersed in the Al matrix uniformly, SiC nanorods were randomly grown on GNPs sheets in any direction, bridging GNPs as well as GNPs and the Al matrix. Meanwhile, the interfacial bonding was effective. The hybrid reinforcement of SiC and GNPs endowed composites with superior mechanical properties and thermal conductivity. The in situ SiC nanorods transfer phonons and reduce phonon scattering effect in the through-plane direction of GNPs, which conducive to heat transmission. The composite exhibits improved mechanical properties, maximum tensile strength and hardness of 589 MPa and 193 HV are obtained, with 1.0 wt% GNPs addition, respectively. The thermal conductivity of composite increases with the content of SiC–GNPs. When the content of SiC–GNPs reaches 1.5 wt%, the composite has significantly enhanced thermal conductivity (224 W m−1 K−1), which is 115% times higher than that of Al2024. Moreover, the effects of SiC–GNPs on the properties were discussed.

When lithium-ion batteries (LIBs) are located at high altitude and low pressure,the characteristics of thermal runaway (TR) and its propagation are different,such as time to TR, the toxicity of TR gases, TR propagation time, mass loss rate, etc. In this article, the author summarized a series of relevant literatures and proposed an instrument that can be used to analyse the TR behavior at different pressure. It is found that: with the decrease of ambient pressure, the TR trigger time becomes longer and the maximum surface temperature decrease. Moreover, the gas released by TR becomes more toxic as the environmental pressure decreases. Beside, the average propagation time between adjacent LIBs is not much difference when the environmental pressure decreases, and when the 18,650 battery module is distributed in a cylindrical shape, the thermal runaway propagation path is basically unchanged as the environmental pressure decreases. This work details TR and its propagation feature under different pressure, and can provide the guidelines for the Air transportation of LIBs.

During the process of liquid forging, a host of hot cracking defects were found in the Al-Cu-Mg-Zn aluminum alloy. Therefore, mechanical tests and analyses by optical microscope, scanning electron microscope, and X-ray diffraction were performed to research the influences of zinc, magnesium, and copper (three main alloying elements) on hot cracking tendency and mechanical properties. It was concluded that all the three alloying elements exerted different effects on the performances of newly designed alloys. And the impact of microstructures on properties of alloys was stronger than that of solution strengthening. Among new alloys, Al-5Cu-4.5Mg-2.5Zn alloy shows better properties as follows: σb=327 MPa, δ=2.7%, HB=107 N/mm2, and HCS=40.

In order to meet the high mobility and lightweight requirements of tracked special vehicles, a novel dual-grouser track shoe component was designed and formed by forging. The thickness of thinnest connection area between two grousers was only 3mm. The low-alloy wear-resisting steel 42CrMo was chosen as the raw material, which enables to solve the drawbacks of non-ferrous metal under the low-intensity-impacting condition. The stress-strain fields of the part during forming were simulated and analyzed using the Finite Element (FE) simulation software, Deform-3D. In addition, the microstructure and mechanical properties of the formed parts demonstrated that the forging process could exhibit a good forming effect with precise dimension and stable quality accomplished. The yield strength, ultimate tensile strength and fracture elongation of the connection area between two grousers were 788MPa, 467MPa and 19.5%. Furthermore, the wear rate and coefficient of friction of this area were 0.015mg/(km·N) and 0.37. Such kind of novel 42CrMo dual-grouser track shoe component is able to offer a lower production costs and longer service duration.

In alkaline in-situ leaching uranium, oxygen is the most common oxidizer with bicarbonate as a complexing agent. For those sandstone uranium deposits with strongly reductive capacity or complicated hydrogeological environment, the oxidation by oxygen is low efficiency. An efficient leaching method, therefore, is needed for these uranium deposits. In this study, a typical sandstone uranium deposit which characterizes with high TDS and high chloride content in groundwater and intractable uranium leach is selected to investigate the effects of synergetic oxidation by a strong oxidant with oxygen. Based on the research on batch leach, pressure leach and field trials, the oxidants such as hydrogen peroxide, potassium permanganate and sodium dichloroisocyanurate (NaDCC) are tested. The results of pressure batch leach indicate that synergetic oxidization is achieved by NaDCC in oxygen leaching process. Leaching tests indicate that a minor oxidizer of NaDCC shows good synergetic oxidization with oxygen and leaching effects on uranium minerals. The results also demonstrate that hydrogen peroxide shows no oxidation effects when it is used as a single oxidant. While potassium permanganate shows good oxidation on uranium when it is used as a single oxidant, however, it leads inhibiting effects on oxygen oxidation on uranium minerals. The further field tests are conducted to study the synergetic effects of oxygen with and without sodium dichloroisocyanurate. The preliminary results indicate that a fast leach is observed by the composite oxidants in early stage while no synergetic leach is found after 200 days. Further studies should be conducted in laboratory experiments and pilot scale tests for its potential applications.

In this study, catalyst formation [Pb(H2O)6][ATZ]·H2O (ATZ = azo tetrazolium anion) was successfully synthesized originally; meanwhile, the single-crystal structure of the compound was cultivated and analyzed by diffraction single-crystal method. The influence of the compound in which [Pb(H2O)6][ATZ]·H2O was used as combustion catalyst on the decomposition temperature of potassium nitrate was studied by TG–DSC. The result proved that [Pb(H2O)6][ATZ]·H2O can effectively reduce the decomposition temperature. In other words, [Pb(H2O)6][ATZ]·H2O can reduce the decomposition temperature of potassium nitrate, so the addition of [Pb(H2O)6][ATZ]·H2O can make potassium nitrate better to be used in the fields of initiating explosive device and fire engineering.

The objective of this study is to investigate the impact of different fractions (0–0.05) of C6F12O addition on laminar flame speed of hydrocarbon syngas by varying the fuel/oxidizer equivalence ratio (0.6–1.2) using Bunsen burner method. The determination of the syngas composition comes from the venting gas of lithium-ion cell during thermal runaway. It is found that C6F12O is significantly more effective at stoichiometric and fuel-rich conditions compared to lean flames regardless of fuel species, which implies more suitable for syngas/air flame inhibition than CH4. The laminar flame speeds of syngas/air increased with lower concentration (

A novel environmental-friendly unpacking powder for fireworks which has no sulfur, no magnesium, no aluminum or their alloys has been prepared in this study: potassium perchlorate (75%), potassium hydrogen terephthalate (13%), micronano porous silicon (9%), carbon (2%), ferrocene (1%). The PM2.5 and PM10 were collected by the ambient air particulate sampler, and the gas product was tested with a smoke analyzer and gas chromatograph to investigate its environmental-friendly performance. The detonation radius was measured by similar triangulation method, and p–t curves were measured in a closed bomb to investigate its practicality. The heat of combustion, sensitivity and hygroscopicity of the formula were measured according to China fireworks industry standard to verify the safety of the novel unpacking powder. The test results suggest that new unpacking powder using micronano porous silicon can effectively reduce the PM content and the product does not contain SO2, so it can be applied to export.

The effects of a variable-cavity liquid forging process on the microstructure and mechanical properties of an Mg-5Zn-1Y-0.6Zr magnesium alloy are described based on the results and analysis. The results indicate that the microstructure of the alloy changed clearly during the deformation process. After variable-cavity liquid forging, the dendrites are elongated along the deformation direction. The alloys with different deformation temperatures consist of α-Mg, the Mg-Zn phase, the I-phase (Mg3YZn6) and the W-phase (Mg3Y2Zn3). The I- and W-phases are mainly distributed in the grain boundaries, and the Mg-Zn phase is mainly dispersed in the grains. Most of second phase is broken into fine particles during the variable-cavity forging process. There is high dislocation density in the elongated grains at a deformation temperature of 350 °C, especially near the grain boundaries. Due to the dislocations, there are some tiny subgrain structures (less than 1 μm) formed near the second phase. After the variable-cavity liquid forging process, the subgrain structures did not recrystallize. The mechanical properties are significantly affected by the second phase and size of the grains. The highest tensile strength is 351.5 MPa at a deformation temperature of 350 °C, which is due to retained eutectic pockets. The best elongation is 7.15% at a deformation temperature of 450 °C, which is due to the tiny second phase particles and fine grains.

Background Limited data exist on VTE risk and prophylaxis in Chinese inpatients. The Identification of Chinese Hospitalized Patients' Risk Profile for Venous Thromboembolism-2 (DissolVE-2), a nationwide, multicenter, cross-sectional study, was therefore designed to investigate prevalence of VTE risks and evaluate VTE prophylaxis implementation compliant with the latest prophylaxis guidelines (American College of Chest Physicians [CHEST], 9th edition). Methods Adults admitted (≥ 72 h) to 60 urban, tertiary Chinese hospitals due to acute medical conditions or surgery from March to September 2016 were assessed for VTE risk. Risk assessments were made by using the Padua Prediction Scoring or Caprini Risk Assessment model, risk factors, and prophylaxis based on the CHEST guidelines, 9th edition. Results A total of 13,609 patients (6,986 surgical and 6,623 medical) were analyzed. VTE risk in surgical inpatients was categorized as low (13.9%; 95% CI, 13.1-14.7), moderate (32.7%; 95% CI, 31.6-33.8), and high (53.4%; 95% CI, 52.2-54.6); risk in medical patients was categorized as low (63.4%; 95% CI, 62.2-64.6) and high (36.6%; 95% CI, 35.4-37.8). Major risk factors in surgical and medical patients were major open surgery (52.6%) and acute infection (42.2%), respectively. Overall rate of any prophylaxis and appropriate prophylactic method was 14.3% (19.0% vs 9.3%) and 10.3% (11.8% vs 6.0%) in surgical and medical patients. Conclusions A large proportion of hospitalized patients reported VTE risk and low rate of CHEST-recommended prophylaxis. The data highlight the insufficient management of VTE risk and show the great potential for improving physicians' awareness and current practices across China. Trial Registry Chinese Clinical Trial Registry; No.: ChiCTR-OOC-16010187; URL: http://www.chictr.org.cn/showproj.aspx?proj=17077.

Thermal runaway and its propagation are bottlenecks for the safe operation of lithium-ion battery systems. This study investigates the influence of characteristic thermophysical parameters during battery thermal runaway, such as the self-heating temperature (T1), triggering temperature (T2), mass loss, and critical heat transfer power (Pc), on the failure propagation behavior in a battery system. A parametric study is conducted based on a failure propagation model. This model not only captures the behavior of thermal failure, but also accounts for the changes in the thermophysical parameters before and after thermal runaway. The results of the modeling analysis demonstrate that increasing T1 and T2 can both delay the thermal runaway propagation. The delay achieved by increasing T2 is greater than that observed by increasing T1. The peak heat transfer power Pc plays a critical role in delaying the thermal runaway propagation. When the peak heat transfer power level is greater than Pc, thermal runaway propagation mainly results from heat transfer, whereas when the peak heat transfer power level is less than Pc, thermal runaway propagation mainly arises from self-heating. This study reveals the dynamic mechanism of thermal runaway propagation within a battery module, thus providing guidance for the safety design of battery systems.

Gas generators are the functional materials producing gas by combustion. In situations such as pneumatics, fire extinguishing bomb, air bag, deep-water salvage, the gas generators can be ignited to provide power and energy through rapid release of gas. However, the research about gas generators with low water vapor is blank in world. The most widely used gas generators (such as nitroguanidine gas generators) produce a lot of water vapor through combustion, whose liquefaction will cause the reduction of gas pressure. This work selected 4,5-diazolyl-1,2,3-triazole (BTTZ) as gas-generating material. Two kinds of gas generator formulations based on BTTZ with common oxometallate (KNO3) and metal oxide (CuO) were designed. The properties of these gas generator formulations were studied by calculation and experiments. The gas production, gas production rate, water vapor content, compatibility and mechanical sensitivity were measured. The gas specific volume of the formulation 1 was 4.08 m3 kg−1. The clean harmless gas content reaches 93.55%. The water vapor content of the product was 6.08% (volume percentage), which is much lower than the nitroguanidine gas generators (53.47%). Therefore, formulation 1 is a low-water vapor environmental-friendly gas generator as a cleaner production material with practical value.

The problem of thermal runaway (TR) propagation challenges the safety design of battery packs, because it aggravates the thermal hazards to accidents. There are many unsolved scientific questions in understanding the mechanisms of TR and its propagation behavior for large format lithium-ion batteries (LIBs). LiNi

In this work, 7075 Al alloy, a high-strength wrought aluminum alloy with high hot tearing sensibility, was used in the squeeze casting of an asymmetric part. The solidification defects, microstructures and mechanical properties of the part solidified under different forming pressures were studied. Furthermore, the uniformities of the microstructures, mechanical properties and the solidification mechanisms were investigated. Results show that increasing the forming pressure is helpful to improve the liquid/solid feeding for counteracting the particularly serious shrinkage during the wide mushy zone of 7075 Al alloy. Therefore, the solidification defect can be avoided. Moreover, increasing the forming pressure is helpful to not only obtaining fine equiaxed grains, but also diminishing the intergranular segregation of alloying elements. With the increasement of forming pressures, the strengths of the part increased, along with the decreases in the ductile due to the work hardening resulted from the serious solid feeding. The microstructures and mechanical properties are impacted by the solidification rate of the melt at different regions. When the forming pressure was 150 MPa, fine microstructures and excellent mechanical properties were obtained. The uniformity of the microstructures and mechanical properties are dominated by the solidification location sequence of the melt. Further on, it is determined by the thermal gradient of the melt at different locations. For 7xxx series alloys, more solid feeding is needed for counteracting the serious shrinkage at the first solidified regions, causing a work hardening and associated strengths increasements. A near uniform part thickness and direct feeding loads are appreciated to improve the uniformities. In this work, the optimal tensile properties tested in the part were tested to be as follows: the yield strength (YS), ultimate tensile strength (UTS), and elongation (EL) are 345.5 MPa, 483.2 MPa, and 7.6%, respectively. The UTS uniformity is tested to be 86.4%.

The development of electric vehicle batteries has resulted in high energy density battery pack. Cell-to-Pack (CTP) omits the cell module assembly, can reduce battery pack parts by 40%, improve the battery pack volume utilization rate by 15%–20%. However, the thermal characteristics of CTP under full operating conditions has yet to be verified, the CTP temperature calibration cycle under full working condition is time-consuming, and little analysis has been conducted on CTP internal temperature differentials and heat flow. The present study aims to thermal characteristics of CTP. Results show that CTP temperature calibration based on a thermal resistance grid can realize internal temperature reconstruction, optimum temperature arrangement, and shorten the calibration period by more than 60%. In addition, higher ambient temperatures can increase the maximum temperature of the jelly rolls in CTP cells, while lower ambient temperature can lead to larger differences in jelly roll temperature within a cell; and high-speed driving and fast charging can lead to the highest temperature increase rates under different working conditions up to 0.05 °C s−1.70% of the heat generated during cell discharge is used for self-heating, and the heat dissipation of liquid cooled plate is the main heat dissipation channel.