Ultra‑Efficient and Cost‑Effective Platinum Nanomembrane Electrocatalyst for Sustainable Hydrogen Production

Hydrogen production through hydrogen evolution reaction(HER)offers a promising solution to combat climate change by replacing fossil fuels with clean energy sources.However,the widespread adoption of efficient electrocatalysts,such as platinum(Pt),has been hindered by their high cost.In this study,we developed an easy-to-implement method to create ultrathin Pt nanomembranes,which catalyze HER at a cost significantly lower than commercial Pt/C and comparable to non-noble metal electrocatalysts.These Pt nanomembranes consist of highly distorted Pt nanocrystals and exhibit a heterogeneous elastic strain field,a characteristic rarely seen in conventional crystals.This unique feature results in significantly higher electrocatalytic efficiency than various forms of Pt electrocatalysts,including Pt/C,Pt foils,and numerous Pt singleatom or single-cluster catalysts.Our research offers a promising approach to develop highly efficient and cost-effective low-dimensional electrocatalysts for sustainable hydrogen production,potentially addressing the challenges posed by the climate crisis.

Antibody-platinum(IV)prodrugs conjugates for targeted treatment of cutaneous squamous cell carcinoma

Antibody-drug conjugates(ADCs)are a new type of targeting antibodies that conjugate with highly toxic anticancer drugs via chemical linkers to exert high specificity and efficient killing of tumor cells,thereby attracting considerable attention in precise oncology therapy.Cetuximab(Cet)is a typical antibody that offers the benefits of good targeting and safety for individuals with advanced and inoperable cutaneous squamous cell carcinoma(cSCC);however,its anti-tumor activity is limited to a single use.Cisplatin(CisPt)shows good curative effects;however,its adverse effects and non-tumor-targeting ability are major drawbacks.In this study,we designed and developed a new ADC based on a new cytotoxic platinum(IV)prodrug(C8Pt(IV))and Cet.The so-called antibody-platinum(IV)prodrugs conjugates,named Cet-C8Pt(IV),showed excellent tumor targeting in cSCC.Specifically,it accurately delivered C8Pt(IV)into tumor cells to exert the combined anti-tumor effect of Cet and CisPt.Herein,metabolomic analysis showed that Cet-C8Pt(IV)promoted cellular apoptosis and increased DNA damage in cSCC cells by affecting the vitamin B6 metabolic pathway in tumor cells,thereby further enhancing the tumor-killing ability and providing a new strategy for clinical cancer treatment using antibody-platinum(IV)prodrugs conjugates.

Association between homologous recombination deficiency and outcomes with platinum and platinum-free chemotherapy in patients with triple-negative breast cancer

Objective:The choice of chemotherapeutic regimen for triple-negative breast cancer(TNBC)remains controversial.Homologous recombination deficiency(HRD)has attracted increasing attention in informing chemotherapy treatment.This study was aimed at investigating the feasibility of HRD as a clinically actionable biomarker for platinum-containing and platinum-free therapy.Methods:Chinese patients with TNBC who received chemotherapy between May 1,2008 and March 31,2020 were retrospectively analyzed with a customized 3D-HRD panel.HRD positivity was defined by an HRD score≥30 or deleterious BRCA1/2 mutation.A total of 386 chemotherapy-treated patients with TNBC were screened from a surgical cohort(NCT01150513)and a metastatic cohort,and 189 patients with available clinical and tumor sequencing data were included.Results:In the entire cohort,49.2%(93/189)of patients were identified as HRD positive(40 with deleterious BRCA1/2 mutations and 53 with BRCA1/2 intact with an HRD score of≥30).In the first-line metastatic setting,platinum therapy was associated with longer median progression-free survival(mPFS)than platinum-free therapy[9.1 vs.3.0 months;hazard ratio(HR),0.43;95%confidence interval 0.22–0.84;P=0.01].Among HRD-positive patients,the mPFS was significantly longer in those treated with platinum rather than platinum-free therapy(13.6 vs.2.0 months;HR,0.11;P=0.001).Among patients administered a platinum-free regimen,HRD-negative patients showed a PFS significantly superior to that of HRD-positive patients(P=0.02;treatment-biomarker P-interaction=0.001).Similar results were observed in the BRCA1/2-intact subset.In the adjuvant setting,HRD-positive patients tended to benefit more from platinum chemotherapy than from platinum-free chemotherapy(P=0.05,P-interaction=0.02).Conclusions:HRD characterization may guide decision-making regarding the use of platinum treatment in patients with TNBC in both adjuvant and metastatic settings.

First-line atezolizumab monotherapy versus single-agent chemotherapy in patients with non-small-cell lung cancer ineligible for treatment with a platinum-containing regimen(IPSOS):a phase 3,global,multicentre,open-label,randomised controlled study

Background:Despite immunotherapy advancements for patients with advanced or metastatic non-small-cell lung cancer(NSCLC),pivotal first-line trials were limited to patients with an Eastern Cooperative Oncology Group performance status(ECOG PS)0-1 and a median age of 65 years or younger.We aimed to compare the efficacy and safety of first-line atezolizumab monotherapy with single-agent chemotherapy in patients ineligible for platinum-based chemotherapy.Methods:This trial was a phase 3,open-label,randomised controlled study conducted at 91 sites in 23 countries across Asia,Europe,North America,and South America.Eligible patients had stage IIIB or IV NSCLC in whom platinum-doublet chemotherapy was deemed unsuitable by the investigator due to an ECOG PS 2 or 3,or alternatively,being 70 years or older with an ECOG PS 0-1 with substantial comorbidities or contraindications for platinum-doublet chemotherapy.Patients were randomised 2:1 by permuted-block randomisation(block size of six)to receive 1200 mg of atezolizumab given intravenously every 3 weeks or single-agent chemotherapy(vinorelbine[oral or intravenous]or gemcitabine[intravenous];dosing per local label)at 3-weekly or 4-weekly cycles.The primary endpoint was overall survival assessed in the intention-to-treat population.Safety analyses were conducted in the safety-evaluable population,which included all randomised patients who received any amount of atezolizumab or chemotherapy.This trial is registered with ClinicalTrials.gov,NCT03191786.

A Graphene-Based Aerogel Was Prepared as Solid Adsorbent for the Enrichment of Platinum (IV) at Trace Concentration

A three-dimensional graphene-based composite was prepared by a simple one-step in-site reduced-oxide method under atmospheric pressure. The obtained hydrogel was modified with 4-amino-benzenesulfonic acid and connected with ethylenediamine, and freeze-dried into an aerogel, which was characterized. Then the surface interaction with platinum (Pt, IV) was explored. The obtained aerogel showed good adsorption for Pt (IV) at acid conditions, giving a rising to the adsorption rate > 98% while pH ≥ 6. Using hexadecyl trimethyl ammonium bromide of 2% (m/V) as an eluent to desorb the Pt (IV) from the surface of the aerogel, a desorption rate of 81.1% was obtained in this process. Urea, buffer aquation and other surfactants were used in the desorption experiment to understand the adsorption mechanism between the aerogel and Pt (IV). In this work, hydrogen bond, van der Waals force and electronic interaction force mainly drove the adsorption process. For obtaining more purified Pt (IV), we used 0.5% CTAB to desorb Pd (II). A new three-dimensional graphene-based composite was prepared and the surface interaction between Pt (IV) and composite was experimented for understanding the adsorption mechanism and exploring its potential application in sample preparation in low concentration.

Cooperative catalytic platinum species accelerating polysulfide redox reactions for Li-S batteries

The shuttle effect derived from diffusion of lithium polysulfides(LiPSs) and sluggish redox kinetic bring about poor cycling stability and low utilization of sulfur,which have always been the key challenging issues for the commercial application of lithium-sulfur(Li-S) batteries.Rational design of cathode materials to catalyze Li_(2)S dissociation/nucleation processes is an appealing and valid strategy to develop high-energy practical Li-S batteries.Herein,considering the synergistic effect of bidirectional catalysis on LiPSs conversion and enhanced chemical immobilization for LiPSs by heteroatom doping,Pt nanoparticles loaded on nitrogen-doped carbon spheres(Pt/NCS composites) were constructed as cathode materials.According to the dynamic evolution of Pt catalysts and sulfur species,Pt~0 and Pt^(2+) species were identified as active species for the accelerated dissociation and nucleation of Li_(2)S,respectively.Meanwhile,in-situ Raman results demonstrated the expedited conversion of sulfur species resulted from bidirectional catalysis of active Pt species,corresponding to boosted redox kinetics.Consequently,Pt/NCS cathode exhibited improved long-term cyclability with high initial capacity,along with enhanced rate capability.This work provides a facile approach to construct cathode materials with bidirectional catalysis on Li_(2)S dissociation/nucleation,and sheds light on a more global understanding of the catalytic mechanism of metal catalysts during LiPSs conversion.

Interfacial engineering of holey platinum nanotubes for formic acid electrooxidation boosted water splitting

Both structure and interface engineering are highly effective strategies for enhancing the catalytic activity and selectivity of precious metal nanostructures.In this work,we develop a facile pyrolysis strategy to synthesize the high-quality holey platinum nanotubes(Pt-H-NTs)using nanorods-like Pt^(Ⅱ)-phenanthroline(PT)coordination compound as self-template and self-reduction precursor.Then,an up-bottom strategy is used to further synthesize polyallylamine(PA)modified Pt-H-NTs(Pt-HNTs@PA).PA modification sharply promotes the catalytic activity of Pt-H-NTs for the formic acid electrooxidation reaction(FAEOR)by the direct reaction pathway.Meanwhile,PA modification also elevates the catalytic activity of Pt-H-NTs for the hydrogen evolution reaction(HER)by the proton enrichment at electrolyte/electrode interface.Benefiting from the high catalytic activity of Pt-H-NTs@PA for both FAEOR and HER,a two-electrode FAEOR boosted water electrolysis system is fabricated by using Pt-H-NTs@PA as bifunctio nal electrocatalysts.Such FAEOR boosted water electrolysis system only requires the operational voltage of 0.47 V to achieve the high-purity hydrogen production,showing an energy-saving hydrogen production strategy compared to traditional water electrolysis system.

Three Dimensional Electric Circuits with Multiple Capacitors and Resistors

Two cubical 3D electric circuits with single and double capacitors and twelve ohmic resistors are considered. The resistors are the sides of the cube. The circuit is fed with a single internal emf. The charge on the capacitor(s) and the current distributions of all twelve sides of the circuit(s) vs. time are evaluated. The analysis requires solving twelve differential-algebraic intertwined symbolic equations. This is accomplished by applying a Computer Algebra System (CAS), specifically Mathematica. The needed codes are included. For a set of values assigned to the elements, the numeric results are depicted.

旋转部件温度参数同步无线测量技术研究

针对旋转部件温度参数原位同步测量和数据无线传输应用需求,研究了电能无线传输技术和空间光通信技术,设计了一套8通道小型温度参数遥测系统。该系统通过热电偶和铂电阻传感器实现8路温度参数的高精度准确测量,采用电磁感应和红外光通信技术实现电能和采集数据的同步无线传输。系统分析软件完成数据的实时存储、解析和可视化显示。搭建了20000 r/min的模拟旋转环境测试平台,进行系统功能和性能验证。系统温度采集精度优于0.15%,无线传输距离为15 mm,电能传输输出峰值功率可达5 V/400 mA,实测通信速率为10 Mbit/s,8通道同步采样速率为56 kHz。该系统实现了温度参数的分布式、高精度获取,为旋转部件的研制和维护提供了准确的温度依据。

从铂化合物制备尾液中回收超细铂粉的研究

将不同的铂化合物制备尾液经过氯化铵沉淀,实现与其他杂质元素的分离,将铂转化为氯铂酸铵中间体,经液相化学还原得到超细铂粉。研究了中间体形态、(NH_(4))2PtCl6溶液浓度、分散剂种类及加入量对铂粉粒度、比表面积、形貌的影响。结果表明,铂化合物尾液种类不影响超细铂粉的形貌及颗粒尺寸,以PVP为分散剂,硼氢化钠为还原剂,在优化条件下制备的铂粉平均粒度约150nm,纯度99.99%,直收率97.8%,颗粒形貌均匀、分散程度高、比表面积及颗粒尺寸均符合超细铂粉国家标准,方法可用于从多种铂类化合物制备尾液直接制备超细铂粉。

计及杂散参数的柔性直流启动电阻冲击电压分布特性研究

针对柔性直流输电系统中启动电阻异常放电问题。首先,从启动电阻温升、绝缘水平、电流应力及冲击能量几方面进行校核分析;然后,对现场启动电阻进行拆解,定量分析启动电阻放电原因;最后,利用Ansys搭建电阻器杂散电容求解模型,根据分布电容求解结果,基于PSCAD搭建电阻塔的宽频等效模型,仿真分析启动电阻在冲击电压下的电位分布规律,验证启动电阻异常放电机理并提出优化改进措施。研究结果可为今后柔性直流输电系统启动电阻的选型设计提供参考。

Pd(111)与Pt(111)上NO氧化的第一性原理研究

随着排放法规的日益严格,发动机的氮氧化物(NO_(x))后处理已成为当今研究的重点问题.针对目前可有效降低稀燃汽油机NO_(x)的稀燃氮氧化物捕集器中铂(Pt)和钯(Pd)两种贵金属之间的替换问题,进行了密度泛函理论(density functional theory,DFT)计算研究.首先,对一氧化氮(NO)、氧气(O_(2))、二氧化氮(NO_(2))在两种催化剂(111)表面的吸附进行了研究,之后,在两催化剂表面对比研究了氧化过程中涉及的O_(2)解离与NO氧化两反应过程,揭示了NO在Pd与Pt催化剂上的氧化机理.结果显示:3种物质在催化剂表面的吸附强度为NO>O_(2)>NO_(2).氧覆盖度将会改变氮氧化物的最佳吸附构型,随着表面氧原子的增加NO会由三重空位式吸附转变为顶点吸附,NO_(2)会由μ-N,O-亚硝基吸附转变为硝基吸附.在O_(2)解离过程中Pt的催化能力优于Pd,但是两者对NO氧化的催化能力接近.在Pd和Pt表面反应限速步骤都是O_(2)的解离,Pd对O_(2)较弱的解离能力导致了其NO的转化效率低于Pt.氧覆盖度对氧化过程存在影响,通过电子结构分析发现,氧覆盖度的提升使催化剂与吸附物质之间的吸附能下降,这导致了反应由吸热变为放热,使催化可以自发进行.反应生成的NO_(2)需要1.00 eV以上的能量完成脱附,这在原子层面解释了NO_(2)对NO氧化反应的抑制作用.

铁捕集法从失效铝基催化剂中富集铂的研究

进行了从失效铝基丙烷脱氢催化剂中回收铂的研究,采用火法熔炼铁捕集法实现铂的高效富集。重点研究了在熔炼温度为1400℃的条件下,熔炼时间、捕集剂(磁铁矿)用量、造渣剂(CaO、SiO_(2))用量、助熔剂(Na_(2)CO_(3)、硼砂)用量对铂回收率的影响。结果表明,在熔炼温度1400℃,熔炼时间4 h,加入质量为失效催化剂60%的磁铁矿、50%的CaO、35%的SiO_(2)、30%的Na_(2)CO_(3)、60%硼砂的条件下,铂平均回收率为99.31%。

基于MMC的分布式储能系统及其快速SOC均衡控制策略

提高基于模块化多电平换流器(modular multilevel converter,MMC)的分布式储能系统(distributed energy storage systems,DESS)的能量利用率,解决储能子模块(energy sub-module,ESM)荷电状态(state of charge,SOC)均衡问题至关重要。针对现有的SOC均衡控制策略的不足,提出内外分层的快速SOC均衡控制策略。外层针对桥臂间或相间的SOC差异,通过改进MMC模型预测控制(model predictive predictive control,MPC),配合自适应均衡系数,快速调整功率差额。内层引入自适应虚拟电阻法,根据ESM的SOC情况确定主导ESM,自适应调节各单元的虚拟电阻,产生相应的电压梯度,结合MMC排序算法使ESM按照各自SOC进行功率分配,从而实现ESM的SOC快速均衡,提高DESS能量利用率。通过在Matlab/Simulink构建仿真模型,证明了所提控制策略的有效性和可行性。

血浆D-二聚体、血栓调节蛋白与上皮性卵巢癌肿瘤细胞减灭术后铂类药物化疗敏感性的关系

目的分析血浆D-二聚体(D-D)、血栓调节蛋白(TM)与上皮性卵巢癌肿瘤细胞减灭术后铂类药物化疗敏感性的关系。方法选取2019年6月至2022年5月唐山市妇幼保健院收治的137例行铂类药物化疗的上皮性卵巢癌患者作为研究对象,均完成肿瘤减灭术,在化疗前进行血液检查,检查项目包括肿瘤标志物、血浆D-D、TM及相关指标。根据化疗结束后复发时间定义复发类型,复发时间<6个月定义为铂耐药复发,反之定义为铂敏感复发,采用Cox回归分析血浆D-D、TM对上皮性卵巢癌肿瘤细胞减灭术后铂耐药复发的影响。结果137例患者成功随访6个月,其中25例在随访6个月内肿瘤复发,铂耐药复发率为18.25%。铂耐药患者国际妇产科联盟(FIGO)分期Ⅳ期、分化程度G_(3)级、手术满意度R1比例高于铂敏感患者,血清糖类抗原125(CA125)、人附睾蛋白4(HE4)、血浆D-D、TM表达高于铂敏感患者(P<0.05)。Cox回归分析结果显示,G_(3)级分化程度、手术满意度R1、血清CA125、HE4及血浆D-D、TM表达上调是上皮性卵巢癌铂耐药复发的影响因素(P<0.05)。结论血浆D-D、TM表达上调与上皮性卵巢癌铂耐药复发风险增加有关,铂类药物化疗前的血浆D-D、TM表达对于评估铂耐药复发风险具有一定意义。

一种新型可移动TEM喇叭辐射波模拟器的模拟优化

为改善基于TEM喇叭的辐射波模拟器的低频辐射特性从而展宽其辐射近场半高宽,首次提出了在指数型TEM喇叭上/下两个极板的端口加上2个金属直板、并通过倾斜金属板和并联电阻相连的新型可移动模拟器的设计方案。基于FDTD方法模拟分析了该新型模拟器的特性参数对其近场辐射性能的影响,并给出了优化后的模拟器及其阵列的辐射特性。计算结果表明:尺寸为6 m×6 m×6.24 m的优化后的新型模拟器在距离口面3 m的中心位置的辐射近场脉宽能达到18.95 ns,而达到相同低频辐射性能的常规模拟器尺寸为9 m×12 m×6.8 m。且与常规模拟器相比,优化后的模拟器的场峰值更大。与前人的研究相比,优化后的模拟器场在保持高峰值的同时,时域波形后延震荡的幅度与主峰的比值明显减小。优化后的模拟器2×2阵列模型的测试平面中心点场峰值最大,且在测试平面上满足6 dB均匀性要求的有效测试区最大;有效测试区在横向上范围最大的是2×2阵列模型,其次是2×1阵列模型;在纵向上范围最大的是2×2阵列模型及1×2阵列模型。

超细铂纳米催化剂的光化学合成及其催化还原硝基苯酚的应用

以乙二醇(EG)为还原剂,通过波长为395 nm近紫外光和450、650 nm的可见光照射C_(60)及K_(2)[PtCl_(4)]混合液,制备了超细铂纳米颗粒(Pt/C_(60)-E)。利用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱(XPS)以及高分辨率透射电子显微镜(HR-TEM)等表征手段对Pt/C_(60)催化剂的组成及形貌进行了研究,结果表明,铂纳米颗粒在C_(60)表面分散良好,平均粒径约为2.6 nm。在催化p-NP还原实验中,在近紫外光(395 nm)照射下所制备催化剂(Pt/C_(60)-E3)表现出最高的催化活性,其速率常数k=0.12 min^(-1)。在催化剂循环实验中,多次循环催化剂仍具有较高的活性,实验证明光化学法对前驱体铂催化剂制备起到良好的作用。

基于铂类耐药相关基因的卵巢癌分型和预后研究

目的本研究利用铂类耐药相关(Platinum resistance-related,PRR)基因对卵巢癌患者进行分型研究,建立预后风险模型,以期为卵巢癌患者临床个体化治疗及相关机制研究提供参考。方法利用单因素Cox回归分析筛选有预后价值的PRR基因,利用无监督共识聚类进行分型,并比较各亚型间预后差异;LASSO回归分析进一步筛选预后相关基因,构建PRR基因预后标签,联合临床信息,构建卵巢癌患者预后风险模型。结果单因素Cox回归分析筛选出68个与患者预后相关的PRR基因,无监督共识聚类获得2个卵巢癌亚型,C1组患者预后较好;12个基因用于构建PRR基因得分(Platinum resistance-related gene score,PRR-GS)预后标签,1、3、5年ROC曲线下面积均高于0.700。多因素Cox回归分析中,年龄、分期和PRR-GS为预后的独立影响因素,模型C指数为0.719,1、3、5年总生存率ROC曲线下面积分别为0.774、0.758、0.768,校准曲线和决策曲线分析表明模型预测效果良好。结论获得卵巢癌患者的2个亚型,各亚型在免疫微环境、预后等方面均存在差异;PRR-GS是独立危险因素,联合临床变量可有效预测患者生存结局。

某电源模块厚膜电阻硫化机理及防护对策

针对本单位某型电子产品内主板的电源模块上的厚膜电阻首次出现硫化的问题,开展了行业现状调研,研究了厚膜电阻硫化机理,分析了电源模块上厚膜电阻硫化的原因。从器件选型、设计优化、工艺改进三个方面提出了提升电源模块抗硫化能力的防护措施。重点论述了涂覆三防漆的改善措施,且经工艺验证可行,能够起到提升电源模块防硫化能力的作用。

奥拉帕利对铂敏感复发BRCA突变卵巢癌患者PD-1/PD-L1信号通路的影响

目的探讨奥拉帕利与含铂方案对铂敏感复发乳腺癌易感基因(BRCA)突变卵巢癌(OC)患者肿瘤血管生成相关因子及程序性死亡受体-1(PD-1)/程序性死亡-配体1(PD-L1)信号通路的影响。方法回顾性选取2018年5月至2020年5月该院95例铂敏感复发BRCA突变OC患者,依据治疗方案不同分为两组,对照组47例接受紫杉类+铂类治疗,观察组48例接受奥拉帕利片。对比两组疗效、安全性、肿瘤血管生成相关因子[血管生成素-2(Ang-2)、血管内皮生长因子(VEGF)、基质细胞衍生因子-1α(SDF-1α)]、外周血CD4^(+)T细胞PD-1、PD-L1水平。结果观察组DCR比对照组高,差异有统计学意义(P<0.05)。观察组恶心、疲劳与乏力、呕吐、贫血、腹泻、白细胞减少、中性粒细胞减少及食欲减退发生率与对照组比较,差异无统计学意义(P>0.05)。观察组治疗3、6个周期血清VEGF、Ang-2及SDF-1α水平低于对照组,差异有统计学意义(P<0.05)。观察组治疗3、6个周期外周血CD4^(+)T细胞PD-1、PD-L1水平低于对照组,差异有统计学意义(P<0.05)。结论奥拉帕利应用于铂敏感复发BRCA突变OC患者中,可调控PD-1/PD-L1信号通路,降低肿瘤血管生成相关因子水平,提升治疗效果。