Effect of two-step solid solution on microstructure andδphase precipitation of Inconel 718 alloy

Inconel 718 is the most popular nickel-based superalloy and is extensively used in aerospace,automotive,and energy indus-tries owing to its extraordinary thermomechanical properties.The effects of different two-step solid solution treatments on microstructure andδphase precipitation of Inconel 718 alloy were studied,and the transformation mechanism fromγ″metastable phase toδphase was clarified.The precipitates were statistically analyzed by X-ray diffractometry.The results show that theδphase content firstly increased,and then decreased with the temperature of the second-step solid solution.The changes in microstructure andδphase were studied by scanning electron microscopy and transmission electron microscopy.An intragranularδphase formed in Inconel 718 alloy at the second-[100]_(δ)[011]γ step solid solution temperature of 925℃,and its orientation relationship withγmatrix was determined as//and(010)_(δ)//(111)γ.Furthermore,the Vickers hardness of different heat treatment samples was measured,and the sample treated by second-step solid solution at 1010℃ reached the maximum hardness of HV 446.84.

Enhanced strengthening by two-step progressive solution and aging treatment in AM50-4%(Zn,Y) magnesium alloy

AM50-4%(Zn,Y)alloy with a Zn/Y mole ratio of6:1was subjected to thermal analysis,and the results were used for designing a two-step progressive solution treatment process.The effects of solution and aging treatments on the microstructure and mechanical properties of the AM50-4%(Zn,Y)alloy were investigated using OM,XRD,SEM/EDS,TEM,tensile test and hardness test.The experimental results demonstrated that the two-step progressive solution treatment could make theΦandβphases sufficiently dissolve into the matrix which possessed higher supersaturated degree of the dissolved solute compared with the one-step solution treatment.This resulted in a certain enhancement of the precipitation strengthening effect during the subsequent aging process.The precipitation of theФphase had a greater impact on the comprehensive mechanical properties of the alloy thanβphase precipitation when the aging treatment was performed at180℃.The peak aging strength of the AM50-4%(Zn,Y)alloy which was subjected to the two-step progressive solution treatment process(345℃for16h and375℃for6h)was obtained after the aging treatment at180℃for12h.

Melt Treatment of Al-7%Si Alloy by Flux Injection

The melt treatment of A1-7%Si alloy by the flux injection method in a resistance furnance was investigated. The experimental results show that the flux injection method can realize the melt treatment of A1-7%Si alloy. In purification, the flux injection method is superior to the standard lance degassing method. For the injection flux, the purifier Na2SiF6 is more powerful than Na3A1F6, the modifiers SrCl2, and R.E. Cl3 are quick acting, like NaF, but less powerful, the grain refiner containing K2TiF6 and KBF4 with Ti/B=1 is more potent than that with Ti/B=5. The analytical results indicate that the mass-transfer rate for the flux injection method is much higher than that for the conventional method .

Heat Treatment of Nd_(1+x)Ba_(2-x)Cu_3O_(7-δ) Superconductors

Two kinds of Nd 1+ x Ba 2- x Cu 3O 7- δ , the sintered samples and zone melted samples, were treated in pure Ar at 950 ℃. The substitution of Nd ions for Ba ions in the Nd 1+ x Ba 2- x Cu 3O 7- δ before and after the heat treatment was investigated by XRD. In order to know the effects of heat treatment, the T c and J c of samples with and without the heat treatment in Ar were comparatively studied. The results show that the substitution of Nd for Ba decreases, whereas T c and J c increase after the treatment. The Nd 1+ x Ba 2- x Cu 3O 7- δ samples were oxygenated in pure oxygen at 300 ℃ . Based on the XRD spectra it was found that the samples with x <0.4 can transform from tetragonal phase into orthorhombic phase after the oxygenation, whereas in the sample with x >0.4 no phase transition occurs even after a long time oxygenation.

Effect of Heat Treatment on Mechanical Properties and Microstructure of NST 37-2 Steel

Engineering materials, mostly steel, are heat treated under controlled sequence of heating and cooling to alter their physical and mechanical properties to meet desired engineering applications. In this study, the effect of heat treatment (annealing, normalising, hardening, and tempering) on the microstructure and some selected mechanical properties of NST 37-2 steel were studied. Sample of steel was purchased from local market and the spectrometry analysis was carried out. The steel samples were heat treated in an electric furnace at different temperature levels and holding times;and then cooled in different media. The mechanical properties (tensile yield strength, ultimate tensile strength, Young’s modulus, percentage reduction, percentage elongation, toughness and hardness) of the treated and untreated samples were determined using standard methods and the microstructure of the samples was examined using metallographic microscope equipped with camera. Results showed that the mechanical properties of NST 37-2 steel can be changed and improved by various heat treatments for a particular application. It was also found that the annealed samples with mainly ferrite structure gave the lowest tensile strength and hardness value and highest ductility and toughness value while hardened sample which comprise martensite gave the highest tensile strength and hardness value and lowest ductility and toughness value.

Interferon-free treatments in patients with hepatitis C genotype 1-4 infections in a real-world setting

AIM To investigated the real-world effectiveness and safety of various regimens of interferon-free treatments in patients infected with hepatitis C virus(HCV).METHODS We performed an observational study to analyze different antiviral treatments administered to 462 HCV-infected patients, of which 56.7% had liver cirrhosis. HCV RNA after 4 wk of treatment and at 12 wk after treatment sustained virologic response(SVR) as well as serious adverse events(SAEs) was analyzed first for the whole cohort and then separately in patients who met or did not meet the inclusion criteria of a clinical trial(CT-met and CT-unmet, respectively).RESULTS The most frequently prescribed treatment was simeprevir/sofosbuvir(36.4%), followed by sofosbuvir/ledipasvir(24.9%) and ombitasvir/paritaprevir/ritonavir(r)/dasabuvir(19.9%). Ribavirin(RBV) was administered in 198 patients(42.9%). SVRs occurred in 437/462 patients(94.6%). The SVRs ranged between 93.3% and 100% for genotypes 1-4. SVRs were achieved in 96.2% patients in the CTmet group vs 91.9% patients in the CT-unmet group(P = 0.049). Undetectable HCV RNA at week 4 occurred in 72.9% of the patients. In the univariate analysis, the factors associated with SVRs were lower liver stiffness, absence of cirrhosis, higher platelet count, higher albumin levels, no RBV dose reduction, undetectable HCV RNA at week 4 and CT-met group. In the multivariate analysis, only albumin was an independent predictor of treatment failure(P = 0.04). Eleven patients(2.4%) developed SAEs; 5.2% and 0.7% of the patients in the CT-unmet and CT-met groups, respectively(P = 0.003).CONCLUSION A high proportion of patients with HCV infection achieved SVRs. For patients who did not meet the CT criteria, treatment regimens must be optimized.

他达拉非片降阶梯治疗慢性前列腺炎合并勃起功能障碍的效果分析

目的探究他达那非片降阶梯治疗应用于慢性前列腺炎勃起功能障碍中的效果。方法随机选取2021年9月—2023年9月江阴市人民医院泌尿外科收治的70例慢性前列腺炎合并勃起功能障碍患者为研究对象,根据不同治疗方法分为参照组(35例,常规治疗)和研究组(35例,他达那非片降阶梯治疗)。比较两组的治疗有效率、前列腺炎症状指数、国际勃起功能指数-5、勃起硬度、前列腺小体外泄蛋白水平、阴茎血流动力学指标。结果研究组治疗总有效率为97.14%(34/35),高于参照组的82.86%(29/35),差异有统计学意义(χ^(2)=3.968,P=0.046)。治疗后,研究组前列腺炎症状指数低于参照组,国际勃起功能指数-5与勃起硬度评分高参照组,差异有统计学意义(P均<0.05)。研究组前列腺小体外泄蛋白水平低于参照组,差异有统计学意义(P<0.05)。研究组阻力指数、舒张末期流速高于参照组,收缩期峰值流速低于参照组,差异有统计学意义(P均<0.05)。结论应用他达那非片降阶梯治疗慢性前列腺炎伴勃起功能障碍,具有明显的临床应用价值。

降阶梯思维护理在急诊创伤患者救治中的应用

目的观察降阶梯思维护理在急诊创伤患者中的应用效果。方法选择急诊科2021年1~12月收治的60例创伤患者作为对照组,2022年1~12月收治的60例创伤患者作为研究组。对照组给予常规护理,研究组行降阶梯思维的急救护理。比较2组患者分诊时间、首诊时间、ECG监测时间、静脉通路开放时间、气道清理时间、呼吸支持时间、检查完成时间、急诊抢救成功率、护理不良事件发生率、患者离开急诊时汉密尔顿焦虑量表和汉密尔顿抑郁量表评分。结果研究组患者分诊时间、首诊时间、ECG监测时间、静脉通路开放时间、气道清理时间、呼吸支持时间、检查完成时间均低于对照组患者,差异均有统计学意义(P<0.05),研究组患者急诊抢救成功率高于对照组患者,护理不良事件发生率低于对照组患者(P<0.05);研究组患者汉密尔顿焦虑量表和汉密尔顿抑郁量表评分均低于对照组,差异均有统计学意义(P<0.05)。结论降阶梯思维护理可有效缩短创伤患者在急救过程中的护理完成时间,降低护理不良安全事件发生率,提高抢救成功率,改善急诊创伤患者焦虑、抑郁情绪。

Effect of Heat Treatment on Gradient Microstructure and Tensile Property of Laser Powder Bed Fusion Fabricated 15-5 Precipitation Hardening Stainless Steel

This work investigated the gradient microstructure evolution and tensile property of LPBF fabricated 15-5 precipitation hardening stainless steel in post-process direct ageing(DA)and solution treating&ageing(STA).The varied microstructures for austenite and small-sized oxide inclusions at different sample heights in the as-built(AB)condition was generally preserved after DA treatment.However,austenite was almost disappeared,and oxide particle grew significantly after the STA treatment.As a result,the tensile property differences in sample top and bottom for AB and DA conditions did not occur in the STA samples.For the influence of post-process heat treatment,the STA condition had the highest yield strength due to the highest volume fraction of nano-sized Cu precipitates.However,the DA specimen had the highest ultimate tensile strength and elongation owing to the considerable amount of austenite phase and associated transformation induced plasticity effect.

368例血流感染患者临床特征、病原与耐药性研究

目的探讨血流感染(BSI)患者临床特征、病原分布与耐药性,为抗菌药物合理使用提供参考。方法调查研究2020年07月—2021年6月期间入住嵊州市两家公立医院确诊为血流感染所有成年患者共368例,分为社区获得BSI与医院获得BSI两组,记录患者人口学资料、临床特征、细菌及药敏结果。结果感染来源前三位分别为腹腔(38.6%)、泌尿道(27.2%)、皮肤软组织及骨关节(9.5%);27例(7.3%)处于免疫抑制状态;173例(47.0%)有近期抗菌药物暴露史。社区获得BSI组腹腔来源比例高于医院获得BSI组(P=0.010),静脉导管来源、免疫抑制状态、抗菌药物暴露比例,APACHEⅡ、PBS评分则低于医院获得BSI组(P<0.05)。368例患者共检出379株细菌,其中革兰阳性球菌108株(28.5%)、革兰阴性杆菌247株(65.2%)、厌氧菌13株(3.4%)、念珠菌属10株(2.6%);检出率前三位细菌依次为大肠埃希菌、肺炎克雷伯菌和肠球菌属,分别占30.1%、18.7%、9.8%;社区获得BSI组大肠埃希菌检出率高于医院获得BSI组(P<0.001),而肠球菌属、非发酵菌和念珠菌属检出率则低于后者(P<0.05)。耐甲氧西林金黄色葡萄球菌(MRSA)比例占43.3%;大肠埃希菌对头孢曲松耐药率为51.8%、肺炎克雷伯菌对亚胺培南耐药率为22.5%。医院获得BSI组肺炎克雷伯菌对氨苄西林/舒巴坦、哌拉西林/他唑巴坦、头孢曲松、头孢他啶、头孢替坦、氨曲南、亚胺培南和妥布霉素耐药率高于社区获得BSI组(P<0.05)。309例(84.0%)治疗有效,59例(16.0%)无效。血流感染发生后28 d死亡率为14.1%(52/368),医院获得BSI组死亡率高于社区获得BSI组(P<0.05);初始广谱抗菌治疗病例中35.5%(78/220)5 d内实施了降阶梯策略,其中降阶梯组死亡率低于非降阶梯组,(P<0.05)。结论本地区BSI病原菌以革兰阴性菌为主,大肠埃希菌和肺炎克雷伯菌是前二位病原菌;医院获得性BSI大肠埃希菌检出率显著减少,非发酵菌、念珠菌检出率和肺炎克雷伯菌耐药率显著提高,同时28d死亡率也显著升高。临床应加强医院感染防控、提升抗菌药物合理应用水平。

Fabrication of high-performance PVA/PAN composite pervaporation membranes crosslinked by PMDA for wastewater desalination

The pyromellitic dianhydride（PMDA） crosslinked poly（vinyl alcohol）（PVA） was coated on top of the PAN ultrafiltration membrane to form a PVA/PAN composite PV membranes for wastewater desalination. The composite membranes have high application value in industrial wastewater treatment. By varying the membrane fabrication parameters including the weight percent（wt%） of the PMDA, the crosslink temperature and duration, membrane with the best desalination performance was obtained. The composite membrane with a 2-lm-thick PVA selective layer containing 20 wt% of PMDA and being crosslinked at 100 °C for 2 h showed the highest Na Cl rejection of 99.98% with a water flux of 32.26 L/（m^2 h）at 70 °C using the 35,000 ppm Na Cl aqueous solution as feed. FTIR spectroscopy, wide-angle X-ray diffraction, thermogravimetric analysis and scanning electron microscope have been used to characterize the structures and properties of both the crosslinked PVA dense films and PVA/PAN composite membranes. The effects of the concentrations of PMDA,the crosslinking time and temperature to the membrane water contact angle, swelling degree, salt rejection and water flux were systematically studied.

Usefulness of ω-3 fatty acid supplementation in addition to mesalazine in maintaining remission in pediatric Crohn's disease: A double-blind, randomized, placebo-controlled study

AIM： To assess the value of long-chain w-3 fatty acids （FAs） supplementation in addition to amino-salicylic-acid （5-ASA） in pediatric patients with Crohn＇s disease （CD）. METHODS： Thirty-eight patients （20 males and 18 females, mean age 10.13 years, range 5-16 years） with CD in remission were randomized into two groups and treated for 12 too. Group Ⅰ （18 patients） received 5-ASA （50 mg/kg/d）＋w-3 FAs as triglycerides in gastroresistant capsules, 3 g/d （eicosapentanoic acid, EPA, 400 mg/g, docosahexaenoic acid, DHA, 200 mg/g）. Group Ⅱ （20 patients） received 5-ASA （50 mg/kg/d）＋olive oil placebo capsules. Patients were evaluated for fatty acid incorporation in red blood cell membranes by gas chromatography at baseline 6 and 12 mo after the treatment. RESULTS： The number of patients who relapsed at 1 year was significantly lower in group I than in group Ⅱ （P〈0.001）. Patients in group I had a significant increase in the incorporation of EPA and DHA （P〈0.001） and a decrease in the presence of arachidonic acids. CONCLUSION： Enteric-coated w-3 FAs in addition to treatment with 5-ASA are effective in maintaining remission of pediatric CD.

Radiation therapy concurrent with weekly cisplatin therapy for loco-regionally advanced nasopharyngeal carcinoma:outcomes of a clinical trial

Objective:The purpose of this study was to define the maximum tolerated dose(MTD) by describing the doselimiting toxicity(DLT) of weekly cisplatin concurrently with conventional plus 3-dimensional conformal radiotherapy(CT + 3DCRT) in patients with loco-regionally advanced nasopharyngeal carcinoma(NPC).Methods:Patients with loco-regionally advanced NPC(III/IVa stage) were enrolled into a dose-escalating study.Toxicity was graded according to Common Terminology Criteria for Adverse Events version 3.0(CTCAE v3.0).MTD was defined when 2 of 6 patients developed DLT.The starting dose of cisplatin was 15 mg/m2/w,with a subsequent dose escalation of 5 mg/m2/w in cohorts of 3 new patients.CT + 3DCRT was given to the nasopharynx and the upper neck;the lower neck was treated by a single anterior field irradiation.The prescription dose was 70-80 Gy by 35-40 fractions to the nasopharynx gross tumor,and 66-70 Gy by 33-35 fractions to the positive neck lymph nodes.Results:From Jun.2008 to Sep.2009,24 patients received complete chemoradiotherapy,and all of them were eligible for toxicity evaluation.On the first five dose levels of 15 mg/m2/w and 35 mg/m2/w,no patient experienced DLT.On the next dose level of 40 mg/m2/w,1 patient experienced DLT of grade 3 myelosuppression for 1.4 weeks,and among the additional 3 patients,no one developed DLT.On the seventh dose level of 45 mg/m2/w,all the patients developed grade 3 myelosuppression for more than 1 weeks,and the dose-escalating trial stopped.The 23(95.8%) patients achieved clinical complete remission(CR) in the local site;22(91.7%) achieved CR in the regional site,and all patients got CR 3 months later.After a median follow-up of 16.4 months,1 patient developed liver metastases 2 months later,1 patient developed bone metastases 10 months later and 22 kept disease-free survival.Conclusion:The MTD of cisplatin weekly with concurrent CT + 3DCRT for local advanced NPC is 40 mg/m2/w,with myelosuppression as DLT.

Change of Ecological Characteristics Due to Decrease of COD/SO_4^(2-) Ratio During Sulfate-reduction

In order to investigate the change of ecological characteristics due to the decrease of COD/SO_4^(2-) ratio during sulfate reduction, continuous-flew tests were conducted in an acidogenic sulfate-reducing reactor with molasses wastewater as sole organic carbon source and sodium snlfate as electron acceptor, and the change of pH value, oxidation reduction potential (ORP), volatile fat acids (VFAs), alkalinity (ALK) and the predominant populations with COD/SO_4^(2-) ratio decreasing from 4.2 to 2.0 were investigated. The experimental results demonstrated that, with decreasing COD/SO_4^(2-) ratio, ORP and ALK increased, pH value decreased, and the proportion of acetic acid in terminal products decreased significantly, and a stable -type microbial community with high COD/SO_4^(2-) ratio was converted into a sub -stable -type one with low COD/SO_4^(2-) ratio.

抗利尿激素不适当分泌综合征(Treatment of the syndrome of inappropriate secretion of antidiuretic hormone)的治疗

抗利尿激素不适当分泌综合征(SIADH)是因多种病理因素引起的抗利尿激素(ADH)分泌异常增多,导致体内水潴留,持续性低钠血症、低渗透压血症、尿呈反常的高渗透压、尿钠排泄增多等现象。由于低钠血症和低血浆渗透压,其临床特征则以脑细胞肿胀(脑水肿)所致中枢神经系统的功能紊乱为主要表现。

Protection Performance of Plasma Sprayed Al_(2)O_(3)-13 wt%TiO_(2) Coating Sealed with an Organic-inorganic Hybrid Agent

An organic-inorganic hybrid sealing agent was fabricated and used in the plasma sprayed Al_(2)O_(3)-13 wt%TiO_(2)coating,and conventional silicone agent was also used for comparison.Protection performance of the coatings was comprehensively evaluated based on both anti-corrosion and anti-biofouling properties.The results reveal that the sealing treatment is remarkably useful to decrease the porosity of the coating,and the porosity of the coating sealed with the hybrid agent is only 0.035%.Immersion corrosion test and Tafel polarization test reveal that the sealed coating with the hybrid agent exhibits a better corrosion resistance by compared with the coating sealed with silicone agent.The corrosion current density i_(corr) of the hybrid agent sealed coating is only 0.7×10^(-6)A·cm^(-2).Moreover,anti-biofouling tests both in the outdoor analogue hydraulic environment and in the natural marine environment prove that the mentioned novel coating presents a better combination of corrosion resistance and anti-biofouling property by compared with the other coatings,and it could be used as a protection of metal components in the marine environment.

Has the time been reached for pseudopolyps to be re-enrolled in endoscopic inflammatory bowel disease scores?

Patients with inflammatory bowel diseases (IBD) represent heterogeneous groups with different characteristics and different clinical course. A great deal of effort is made to discover proxies for more severe disease needing more intense treatment and early intervention to gain the maximum therapeutic benefit. Endoscopy remains an invaluable method in assessment of patients with IBD. Pseudopolyps are often encountered during endoscopy and, although they are a well described entity, their presence is of unclear importance. In one of our recent studies and in conjunction with one study with a large cohort of patients with IBD and pseudopolyps, patients with pseudopolyps were found to face a higher inflammatory burden in terms of receiving more intense biological treatment. This letter comes as a comment and proposition regarding the concept of reevaluation of pseudopolyps as a promising marker in IBD scores.

Corrosion Resistance of Heat-Treated NST 37-2 Steel in Hydrochloric Acid Solution

Corrosion of metal components constitutes a major challenge in many engineering systems, with appropriate design, proper material selection, and heat treatment as commonly used control strategies. In this study, the corrosion behaviour of heat-treated (annealed, normalised, hardened, and tempered) NST 37-2 steel in three concentrations (1.0, 1.5 and 2.0 M) of hydrochloric acid solution was investigated using weight loss and electrode-potential methods. Results showed that corrosion rate increased with increase in acid concentration. The decreasing order of corrosion resistance was Tempered > Annealed > Normalised > Hardened > Untreated. The surface pictures of the heat-treated and untreated samples showed uniform and pitting corrosion with the latter becoming more pronounced as concentration increased.

THE SCROOPING TREATMENT OF POLYESTER SILKLIKE FIBERS

In this paper the mechanism producing scrooping sound has been discussedtheoretically.It has been recognized that the continuous stick-slip vibrationhaving a certain period and the bigger △E(△E——enery released by stick-slipvibration at one time)are the requisite and surfficient conditions producingscrooping sound.For fiber sample,its surface properties and internal structureare two principal factors influencing scrooping sound. Considering the surface properties of polyester fiber after scrooping treatmentare the synthetic reflection of the properties used treatment reagents and thesurface properties of the fiber,how selecting proper reagents for scroopingtreatment would be the key factor influencing the scrooping effect.Sometreatment solutions having better scrooping effect have been obtained in the paper. In order to cause better scrooping effect,not only the treatment reagent andsurface properties of the fiber,but also the internal structure of the fiber must beconsidered,It has been shown in

The Influence of Ceramic Coating on Fatigue Crack Growth Behaviour of X17CrNi15-2 Stainless Steel

Fatigue crack growth tests were carried out on the SEN B3 precracked specimens, with dimensions in accordance with ISO 12108 requirements. The specimens were made of martensitic stainless steel, X17CrNi15-2, and some of them were modified by the ceramic coating deposition surface treatment. The effects of ceramic coating, on the fatigue crack growth behaviour of hollow shaft specimens, were experimentally investigated. Fatigue crack growth rates, da/dN, were characterised, using the power law relationship between da/dN (in mm/cycle) and the stress intensity factor range, ΔK (in MPa&#8729;m0.5). The two constants of the correlation are 7.9768 × 10&#8722;9 and 2.8107 for the parent material, and those for the coated material are 2.4391 × 10&#8722;9 and 3.1990, respectively. Microstructural analyses were carried out on the tested specimens, which shows that the maximum hardness of the ceramic coating is higher than that of substrate by a factor of ~3.2. The dimple fracture dominates the final fracture mechanism for the parent material, and the combination of fatigue, ductile fracture and cleavage dominates the final fracture mechanism for the coated material, based on the SEM analyses. EDS tests’ results reveal that the parent material specimen shows higher levels of C at matrix regions along with Fe- and O-rich regions, compared with the coated material specimen.