Effect of hot isostatic pressing processing parameters on microstructure and properties of Ti60 high temperature titanium alloy

Hot isostatic pressing parameters are critical to Ti60 high temperature titanium alloy castings which have wide application perspective in aerospace.In order to obtain optimal processing parameters,the effects of hot isostatic pressing parameters on defects,composition uniformity,microstructure and mechanical properties of Ti60 cast high temperature titanium alloy were investigated in detail.Results show that increasing temperature and pressure of hot isostatic pressing can reduce defects,especially,the internal defects are substantially eliminated when the temperature exceeds 920℃or the pressure exceeds 125 MPa.The higher temperature and pressure can improve the microstructure uniformity.Besides,the higher pressure can promote the composition uniformity.With the temperature increases from 880℃to 960℃,α-laths are coarsened.But with increasing pressure,the grain size of prior-βphase,the widths ofα-laths andα-colony are reduced.The tensile strength of Ti60 alloy is 949 MPa,yield strength is 827 MPa,and the elongation is 11%when the hot isostatic pressing parameters are 960℃/125 MPa/2 h,which exhibits the best match between the strength and plasticity.

Mechanisms of hepatic ischemia-reperfusion injury and protective effects of nitric oxide

Hepatic ischemia-reperfusion injury(IRI) is a patho-physiological event post liver surgery or transplantation and significantly influences the prognosis of liver func-tion. The mechanisms of IRI remain unclear, and effec-tive methods are lacking for the prevention and therapy of IRI. Several factors/pathways have been implicated in the hepatic IRI process, including anaerobic metabo-lism, mitochondria, oxidative stress, intracellular cal-cium overload, liver Kupffer cells and neutrophils, and cytokines and chemokines. The role of nitric oxide(NO)in protecting against liver IRI has recently been report-ed. NO has been found to attenuate liver IRI through various mechanisms including reducing hepatocellular apoptosis, decreasing oxidative stress and leukocyte adhesion, increasing microcirculatory flow, and enhanc-ing mitochondrial function. The purpose of this review is to provide insights into the mechanisms of liver IRI, indicating the potential protective factors/pathways that may help to improve therapeutic regimens for control-ling hepatic IRI during liver surgery, and the potential therapeutic role of NO in liver IRI.

Neuroprotective effects of Activin A on endoplasmic reticulum stress-mediated apoptotic and autophagic PC12 cell death

Activin A, a member of the transforming growth factor-beta superfamily, plays a neuroprotective role in multiple neurological diseases. Endoplasmic reticulum(ER) stress-mediated apoptotic and autophagic cell death is implicated in a wide range of diseases, including cerebral ischemia and neurodegenerative diseases. Thapsigargin was used to induce PC12 cell death, and Activin A was used for intervention. Our results showed that Activin A significantly inhibited morphological changes in thapsigargin-induced apoptotic cells, and the expression of apoptosis-associated proteins [cleaved-caspase-12, C/EBP homologous protein(CHOP) and cleaved-caspase-3] and biomarkers of autophagy(Beclin-1 and light chain 3), and downregulated the expression of thapsigargin-induced ER stress-associated proteins [inositol requiring enzyme-1(IRE1), tumor necrosis factor receptor-associated factor 2(TRAF2), apoptosis signal-regulating kinase 1(ASK1), c-Jun N-terminal kinase(JNK) and p38]. The inhibition of thapsigargin-induced cell death was concentration-dependent. These findings suggest that administration of Activin A protects PC12 cells against ER stress-mediated apoptotic and autophagic cell death by inhibiting the activation of the IRE1-TRAF2-ASK1-JNK/p38 cascade.

Identification of risk factors for poor language outcome in surgical resection of glioma involving the arcuate fasciculus:an observational study

The arcuate fasciculus is a critical component of the neural substrate of human language function.Surgical resection of glioma adjacent to the arcuate fasciculus likely damages this region.In this study,we evaluated the outcome of surgical resection of glioma adjacent to the arcuate fasciculus under the guidance of magnetic resonance imaging and diffusion tensor imaging,and we aimed to identify the risk factors for postoperative linguistic deficit.In total,54 patients with primary glioma adjacent to the arcuate fasciculus were included in this observational study.These patients comprised 38 men and 16 women(aged 43±11 years).All patients underwent surgical resenction of glioma under the guidance of magnetic resonance imaging and diffusion tensor imaging.Intraoperative images were updated when necessary for further resection.The gross total resection rate of the 54 patients increased from 38.9%to 70.4%by intraoperative magnetic resonance imaging.Preoperative language function and glioma-to-arcuate fasciculus distance were associated with poor language outcome.Multivariable logistic regression analyses showed that glioma-to-arcuate fasciculus distance was the major independent risk factor for poor outcome.The cutoff point of glioma-to-arcuate fasciculus distance for poor outcome was 3.2 mm.These findings suggest that intraoperative magnetic resonance imaging combined with diffusion tensor imaging of the arcuate fasciculus can help optimize tumor resection and result in the least damage to the arcuate fasciculus.Notably,glioma-to-arcuate fasciculus distance is a key independent risk factor for poor postoperative language outcome.This study was approved by the Ethics Committee of the Chinese PLA General Hospital,China(approval No.S2014-096-01)on October 11,2014.

Microstructure and mechanical properties of laser additive manufactured novel titanium alloy after heat treatment

A novel α+β titanium alloy with multi-alloying addition was designed based on the cluster formula 12[Al-Ti_(12)](AlTi_(2))+5[Al-Ti_(14)](AlV_(1.2)Mo_(0.6)Nb_(0.2))which was derived from Ti-6Al-4V.The nominal composition of this novel alloy was determined as Ti-6.83Al-2.28V-2.14Mo-0.69Nb-6.79Zr.In this study,the novel alloy and Ti-6Al-4V alloy samples were prepared by laser additive manufacturing.The microstructure,micro-hardness,room/high temperature tensile properties of the as-deposited samples were investigated.Compared to Ti-6Al-4V,the novel alloy has much higher room and high temperature(600℃)tensile strengths,which are 1,427.5 MPa and 642.2 MPa,respectively;however,it has a much lower elongation(3.2%)at room temperature because of the finer microstructure.To improve the elongation of the novel alloy,heat treatment was used.After solution at 960℃ or 970℃ for 1 h followed by air cooling and aging at 550℃ for 4 h followed by air cooling,a unique bi-modal microstructure which contains crab-like primaryαand residual β phase is obtained,improving the compression elongation by 80.9% compared to the as-deposited samples.The novel alloy can be used as a high-temperature and high-strength candidate for laser additive manufacturing.

STUDY ON THE SUSTAINABLE DEVELOPMENT OF WETLAND RESOURCES IN THE USSURI /WUSULI RIVER BASIN

The Ussuri/Wusuli River basin joins the border between the Northeast region of Heilongjiang Province of China and the Far East region of Russia. The watershed consists of approximately 26 000 000 ha and the shared border stretches more than 1100 km. The Ussuri River forms part of the border between Russia and China. Two thirds of the watershed ecosystem is in Russia, one third in China. Khanka / Xingkai Lake is the border Lake of Russia and China, with the area of 4380 km2. The Ussuri / Wusuli River Basin is rich in wetland resources, including surface water resources and wetlands. There are about more than 100 rivers belonging to one and two branch rivers, wetlands are mainly distributed in the Sanjiang Plain in China, which is the largest marsh area in China, with an area of 114 million ha. Human activities and agriculture reclamation for many years have led to many environment problems: 1)decreasing of wetland area led to loss of wetland environment functions, decreasing of biodiversity and increasing the number of natural disasters such as disastrous drought and waterlogging, which affect directly sustainable utilization of resources and economical development. 2) water supply is not evenly distributed, water pollution in rivers, marshes and lakes are more serious than before. Based on above study, some suggests of sustainable development in the basin have been made, which include: 1) developing the international wetland natural reserve and domestic comprehensive protected area to prevent wetlands from destruction and disturbance by human activities, 2) strengthening the protection and management of wetlands in lake shorelines and riparian zones (rivers and streams) to prevent water quality of rivers and lakes from pollution, 3) restoring the destroyed marsh in riparian zones and the  island like forests" of wetlands 4) developing positively transnational ecological tourist trade to promote the economic development in the river basin scope, 5) developing international cooperation research to promote sustainable utilization and protection of wetland resources.

Composition formula of Al-TMs high-entropy alloys derived by cluster-plus-glue-atoms model and its experimental verification

High-entropy alloys(HEAs)are based on solid solutions which characterized by chemical short-range ordering(CSRO),but there is no accurate structural tool to address CSRO characteristic,which obstacles precise composition design for HEAs.In this study,based on the cluster-plus-glue-atoms model,the composition law of Al-TMs(TMs,transition metals)HEAs with BCC and FCC structures was revealed.In BCC structure,with five elements in equi-atomic ratio,the composition formula of Al-TMs HEAs can be expressed by a cluster formula[Al-M_(14)]Al_(3),and in non equi-atomic ratio can be expressed by[Al-M_(14)]Al,where M is the average atom of the TMs.But in FCC structure,both Al-TMs HEAs with five elements in equiatomic and non equi-atomic ratios can be expressed by a cluster formula[Al-M_(12)]Al.To confirm the effectiveness of cluster formula for Al-TMs,two alloys were designed,[Al-Ti_(4)V_(3)Nb_(4)Mo_(3)]Mo and[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]Al.Results show that the[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]Al alloy has both higher strength and higher plastic deformation at room temperature.Besides,[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]Al alloy shows slower soften effect at 800℃,contributed to its higher strength.By substituting Ta for some of Mo,the strength of[Al-Ti_(3)V_(3)Nb_(4)Mo_(3)Ta]Al at room temperature and high temperature drastically decreases,suggesting that Ta element deteriorates the properties of Al-TMs alloys.

Effects of intensive psychological intervention on treatment compliance,psychological status,and quality of life of patients with epilepsy

BACKGROUND Epilepsy is a nervous system disease characterized by recurrent attacks,a long disease course,and an unfavorable prognosis.It is associated with an enduring therapeutic process,and finding a cure has been difficult.Patients with epilepsy are predisposed to adverse moods,such as resistance,anxiety,nervousness,and anxiety,which compromise treatment compliance and overall efficacy.AIM To explored the influence of intensive psychological intervention on treatment compliance,psychological status,and quality of life(QOL)of patients with epilepsy.METHODS The clinical data of 105 patients with epilepsy admitted between December 2019 and July 2023 were retrospectively analyzed,including those of 50 patients who underwent routine intervention(control group)and 55 who underwent intensive psychological intervention(research group).Treatment compliance,psychological status based on the Self-Rating Anxiety Scale(SAS)and Depression Scale Self-Rating Depression Scale(SDS)scores,hope level assessed using the Herth Hope Scale(HHS),psychological resilience evaluated using the Psychological Resilience Scale,and QOL determined using the QOL in Epilepsy-31 Inventory(QOLIE-31)were comparatively analyzed.RESULTS Treatment compliance in the research group was 85.5%,which is significantly better than the 68.0%of the control group.No notable intergroup differences in preinterventional SAS and SDS scores were identified(P>0.05);however,after the intervention,the SAS and SDS scores decreased significantly in the two groups,especially in the research group(P<0.05).The two groups also exhibited no significant differences in preinterventional HHS,Connor-Davidson Resilience Scale(CD-RISC),and QOLIE-31 scores(P>0.05).After 6 months of intervention,the research group showed evidently higher HHS,CD-RISC,tenacity,optimism,strength,and QOLIE-31 scores(P<0.05).CONCLUSION Intensive psychological intervention enhances treatment compliance,psychological status,and QOL of patients with epilepsy.

新型冠状病毒感染的肺炎传播期间武汉“污名化”现象成因及其对策初探

2019年年底新型冠状病毒感染的肺炎爆发后,全国范围内出现了对武汉和武汉人“污名化”现象,基于此,本研究循证检索了我国国情的关于疾病形成“污名化”问题的相关文献,并给予这些文献归纳总结因为疾病而进行“污名化”现象的主要原因以及解决对策,与当前武汉“污名化”现象进行比照后,从国家层面、社区和社会组织层面、民众层面提出在此次疫情中更为具体的解决措施,希冀为疫情防控以及未来的相关社会事件的治理方法提出可行方案。

Effect of V and N on Microstructures and Properties of Grade-70 Tire Cord Steel during Cold Drawing

Commercial grade-70 tire cord steel was microalloyed with V and N to explore the possibility of substituting V for C and the effect of V and N on cementite dissolution during cold drawing process.Tensile strength,elongation and torsion laps of cold-drawn wires were determined.Microstructures of secondary phases were studied by transmission electron microscopy(TEM)and energy dispersive spectroscopy(EDS).Saturation magnetization was measured by using a vibrating sample magnetometer(VSM)to evaluate cementite dissolution during cold drawing process.Experimental results showed that with the increase of V content,tensile strength increased,elongation slightly decreased,and the torsion laps of the cold-drawn wires decreased.Results also showed that with the increase of N content,apeak(increasing first and then decreasing)appeared in the tensile strength graph,and an increase of elongation and a decrease of torsion laps of the cold-drawn wires occured.N is soluble in ferrite when its content is low.The increase in the content of N to 82×10-6 will result in the precipitation of the V-containing secondary phases.Also,cementite tended to be stable during cold drawing process with the increase of V and N contents.Grade-80 tire cord steel can be replaced by grade-70 tire cord steel microalloyed with 0.086mass% V.