醇硫基丙烷磺酸钠对电解高性能锂电铜箔的影响

电解铜箔因其工艺简单、经济价值高,已广泛应用于印制线路板和锂离子电池领域。研究表明在电解制箔过程中,加入微量添加剂即可大幅度提高电解铜箔性能。因此,在基础电解液(312.5 g·L^(-1)CuSO_(4)·5H_(2)O,100 g·L^(-1)H_(2)SO_(4),50 mg·L^(-1)Cl^(-))基础上,加入添加剂考察了电解液的电化学行为以及对铜箔表面形貌、结构以及性能的影响。实验选取了醇硫基丙烷磺酸钠(HP)、水解蛋白(HVP)和N,N-二甲基硫代甲酰胺丙烷磺酸钠(DPS)作为组合添加剂,利用扫描电镜(SEM)、X射线洐射(XRD)以及电化学分析等方法,重点考察了组合添加中HP对铜箔表面形貌和物理性能的影响。研究结果表明,在组合添加剂体系中HP具有较强的去极化作用,可以加速铜核的生长,且具有增强铜(200)晶面的择优生长取向。HP与DPS、HVP的协同作用可以进一步减小电解铜箔的晶粒尺寸,降低表面粗糙,提高铜箔力学性能和耐腐蚀性能。所制备的电解铜箔均匀致密,平均晶粒尺寸为29.2 nm、平均粗糙度为1.12μm、平均抗拉强度为399.5 MPa且耐蚀性能优越,是锂离子电池负极集流体的理想材料,具有较高的商业价值。

酸性溶液中苯并三氮唑和3-巯基-1-丙烷磺酸钠在铜电极表面的电化学SERS研究

利用原位电化学表面增强拉曼光谱技术(EC-SERS)研究了酸性溶液中苯并三氮唑(BTAH)、3-巯基-1-丙烷磺酸钠(MPS)及Cl-在铜电极表面的竞争吸附行为。在较正电位区间,BTAH分子在铜电极表面的吸附主要是通过三唑环在铜电极表面形成[Cu(BTA)]_(n)聚合物膜;随着电位负移,聚合物膜逐渐转化为BTAH分子形式吸附在铜电极表面。而MPS主要是以巯基端吸附在铜电极表面,其吸附方向的改变使得其在铜表面的拉曼信号呈现出先强后弱的趋势。Cl-主要是以Cu-Cl的形式存在,占据电极表面的活性位点与MPS产生协同作用。当三者复配时是以BTAH在电极表面的强吸附性为主导,且随着电位的负移,BTAH的拉曼信号呈现出先增强再减弱的趋势,相较于BTAH的强吸附作用,MPS与Cl-在电极表面的吸附强度较弱但依旧可以监测到两者参与竞争吸附的过程。

低电压电沉积类金刚石碳膜的研究

采用电化学沉积法,在较低电压下(4.0~8.0 V)以甲酸作为主要碳源,甲酸钠作为辅助碳源,二甲基亚砜与去离子水作为溶剂,在不锈钢表面制备了类金刚石碳薄膜,研究了沉积电压对碳膜形貌和成分的影响。电化学沉积含氢类金刚石碳薄膜致密、均匀,膜的电导率与沉积电压呈负相关关系,电导率介于金属与半导体之间。拉曼光谱在1332 cm^(-1)处出现金刚石的特征峰,sp^(3)碳成分随沉积电压的增加而增加。傅里叶红外变换光谱显示沉积的类金刚石碳膜为含氢碳膜。X射线光电子能谱分析显示这些薄膜中存在sp^(2)和sp^(3)键碳原子。

Structural characteristics and high-temperature tribological behaviors of laser cladded NiCoCrAlY−B_(4)C composite coatings on Ti6Al4V alloy

In order to improve the hardness and tribological performance of Ti6Al4V alloy,NiCoCrAlY-B_(4)C composite coatings with B_(4)C of 5%,10%and 15%(mass fraction)were fabricated on its surface by laser cladding(LC).The morphologies,chemical compositions and phases of obtained coatings were analyzed using scanning electronic microscope(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD),respectively.The effects of B_(4)C mass fraction on the coefficient of friction(COF)and wear rate of NiCoCrAlY-B_(4)C coatings were investigated using a ball-on-disc wear tester.The results show that the NiCoCrAlY-B_(4)C coatings with different B_(4)C mass fractions are mainly composed of NiTi,NiTi_(2),α-Ti,CoO,AlB_(2),TiC,TiB and TiB_(2)phases.The COFs and wear rates of NiCoCrAlY-B_(4)C coatings decrease with the increase of B_(4)C content,which are contributed to the improvement of coating hardness by the B_(4)C addition.The wear mechanisms of NiCoCrAlY-B_(4)C coatings are changed from adhesive wear and oxidation wear to fatigue wear with the increase of B_(4)C content.

Cholesterol paradox in the community-living old adults:is higher better?

OBJECTIVE To evaluate the associations of lipid indicators and mortality in Beijing Elderly Comprehensive Health Cohort Study.METHODS A prospective cohort was conducted based on Beijing Elderly Comprehensive Health Cohort Study with 4499 com-munity older adults.After the baseline survey,the last follow-up was March 31,2021 with an average 8.13 years of follow-up.Cox proportional hazard model was used to estimate the hazard ratios(HR)with 95%CI for cardiovascular disease(CVD)death and all-cause death in associations with baseline lipid indicators.RESULTS A total of 4499 participants were recruited,and the mean levels of uric acid,body mass index,systolic blood pres-sure,diastolic blood pressure,fasting plasma glucose,total cholesterol(TC),triglyceride,and low-density lipoprotein cholesterol(LDL-C)showed an upward trend with the increasing remnant cholesterol(RC)quarters(Ptrend<0.05),while the downward tr-end was found in high-density lipoprotein cholesterol(HDL-C).During the total 36,596 person-years follow-up,the CVD mortal-ity and all-cause mortality during an average 8.13 years of follow-up was 3.87%(95%CI:3.30%-4.43%)and 14.83%(95%CI:13.79%-15.86%)with 174 CVD death participants and 667 all-cause death participants.After adjusting for confounders,the higher level of TC(HR=0.854,95%CI:0.730-0.997),LDL-C(HR=0.817,95%CI:0.680-0.982)and HDL-C(HR=0.443,95%CI:0.271-0.724)were associated with lower risk of CVD death,and the higher level of HDL-C(HR=0.637,95%CI:0.501-0.810)were associated with lower risk of all-cause death.The higher level of RC(HR=1.276,95%CI:1.010-1.613)increase the risk of CVD death.Com-pared with the normal lipid group,TC≥6.20 mmol/L group and LDL-C≥4.10 mmol/L group were no longer associated with lower risk of CVD death,while RC≥0.80 mmol/L group was still associated with higher risk of CVD death.In normal lipid gr-oup,the higher levels of TC,LDL-C and HDL-C were related with lower CVD death.CONCLUSIONS In community older adults,higher levels of TC and HDL-C were associated with lower CVD mortality in normal lipid reference range.Higher RC was associated with higher CVD mortality,which may be a better lipid indicator for es-timating the CVD death risk in older adults.

Risk factors related to significant hepatic inflammation in patients with acute drug-induced liver injury

Background and aims:Currently,research on biopsy-proven acute drug-induced liver injury(DILI)remains limited.This study aimed to identify clinical characteristics and risk factors for significant hepatic inflammation in patients with acute DILI.Methods:An ambispective cohort study was conducted on biopsy-proven acute DILI patients admitted to our hospital from 2012 to 2018.Using the Scheuer scoring system,patients were categorized into G0-2 or G3-4 groups and followed up for 12 months after first admission.Clinical characteristics and outcomes were retrieved from medical records.Results:The median age of the 157 enrolled patients(65.6%female)was 40.4(interquartile range(IQR),31.9-49.1)years.The median latency and length of hospitalization were 30.0(IQR,5.0-60.0)and 18.0(IQR,12.0-26.0)days.The proportions of patients in the G0-2 and G3-4 groups were 54.8%and 45.2%,respectively.Logistic regression analysis revealed that females(odds ratio(OR):2.623,95%confidence interval(CI):1.169-5.887,p=0.019),higher body mass index(OR:1.168,95%CI:1.029-1.325,p=0.016),higher total bilirubin(OR:1.004,95%CI:1.000-1.007,p=0.047),and lower prothrombin activity(OR:0.976,95%CI:0,957-0.995,p=0.013)were associated with significant hepatic inflammation.The predominance of the hepatocellular injury pattern(60.5%)at admission transformed into a predominance of the cholestatic pattern(60.5%)at discharge.During follow-up,23 patients(14.6%)developed chronic DILI,with nine patients(5.7%)progressing to cirrhosis.Moreover,15 female patients(9.6%)developed autoimmunity(3cases in the G0-2 group vs 12 cases in the G3-4 group,p<0.05).Conclusion:Acute DILI patients with high-risk factors were more likely to develop significant hepatic inflammation,and females with significant inflammation were at a higher risk of developing autoimmunity during follow-up.

Friction and wear properties of AlCrN coating by cathodic arc ion plating

AlCrN coating was prepared on the surface of TiC-based cermet cutting tool with cathodic arc ion plating,and the surface-interface morphologies,compositions of chemical elements,and phases were analyzed by scanning electron microscope(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD),respectively.Bonding strength of the coating-substrate interface was measured with scratching test,and the wear mechanism and friction coefficient of TiC-based cermet cutting tool and AlCrN coating were investigated with friction and wear testing machine.The results show that the interface binding of AlCrN coating is metallurgical mode,and its binding strength is 83 N.The average friction coefficient of TiC-based cermet cutting tool under the load of 6 N is 0.8409,while that under the load of 8 N decreases by about 11%,and the wear mechanism of TiC cermet cutting tool is fatigue wear,abrasive wear,and oxidation wear.The average friction coefficient of AlCrN coating is 0.6363 under the load of 6 N,and the change is relatively stable,decreasing by about 25%than that of TiC-based cermet cutting tool;when the load increases to 8 N,the average friction coefficient of AlCrN coating decreases by 9%.The wear mechanism of AlCrN coating is abrasive wear and oxidation wear,showing lower friction coefficient and good wear resistance.