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Ultra‑Efficient and Cost‑Effective Platinum Nanomembrane Electrocatalyst for Sustainable Hydrogen Production
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作者 Xiang Gao Shicheng Dai +8 位作者 Yun Teng Qing Wang Zhibo Zhang Ziyin Yang Minhyuk Park Hang Wang Zhe Jia Yunjiang Wang Yong Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期95-110,共16页
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 electro... 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. 展开更多
关键词 platinum Hydrogen evolution reaction Lattice distortion Heterogeneous strain
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Phase composition,conductivity,and sensor properties of cerium-doped indium oxide
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作者 M.I.Ikim G.N.Gerasimov +2 位作者 V.F.Gromov O.J.Ilegbusi L.I.Trakhtenberg 《Nano Materials Science》 EI CAS CSCD 2024年第2期193-200,共8页
The hydrothermal synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these compounds.During the synthesis of In_(2)O_(3),intermediate products In(OH)_(3)... The hydrothermal synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these compounds.During the synthesis of In_(2)O_(3),intermediate products In(OH)_(3)and InOOH are formed,which are the precursors of stable cubic(c-In_(2)O_(3))and metastable rhombohedral(rh-In_(2)O_(3))phases,respectively.A transition from c-In_(2)O_(3)to rh-In_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-In_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)O_(3).The data on the sensor activity of the composites correlate with XPS results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)O_(3).The reverse situation is observed in composites based on c-In_(2)O_(3).Compared to In_(2)O_(3)and CeO_(2)–In_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)O_(3)and CeO_(2). 展开更多
关键词 cerium oxide Indium oxide NANOCOMPOSITE Hydrothermal method Cubic phase Rhombohedral phase Sensor response CONDUCTIVITY HYDROGEN Response/recovery time
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Association between homologous recombination deficiency and outcomes with platinum and platinum-free chemotherapy in patients with triple-negative breast cancer 被引量:2
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作者 Yimeng Chen Xue Wang +8 位作者 Feng Du Jian Yue Yiran Si Xiaochen Zhao Lina Cui Bei Zhang Ting Bei Binghe Xu Peng Yuan 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第2期155-168,共14页
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 treatm... 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. 展开更多
关键词 Homologous recombination deficiency triple-negative breast cancer platinum SURVIVAL BRCA
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Cerium-tungsten oxides supported on activated red mud for the selective catalytic reduction of NO_(x) 被引量:1
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作者 Qiuzhun Chen Dong Wang +7 位作者 Chuan Gao Bin Wang Shengli Niu Gaiju Zhao Yue Peng Junhua Li Chunmei Lu John Crittenden 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期173-182,共10页
Activated red mud(RM)has been proved to be a promising base material for the selective catalysis reduction(SCR)of NOx.The inherent low reducibility and acidity limited its low-temperature activity.In this work,molybde... Activated red mud(RM)has been proved to be a promising base material for the selective catalysis reduction(SCR)of NOx.The inherent low reducibility and acidity limited its low-temperature activity.In this work,molybdenum oxide,tungsten oxide,and cerium oxide were used to reconfigure the redox sites and acid sites of red mud based catalyst.When activated red mud was reconfigured by cerium-tungsten oxide(Ce-W@RM),the NOx conversion kept above 90%at 219-480℃.The existence of Ce^(3+)/Ce^(4+) redox electron pairs provided more surface adsorbed oxygen(O_(α)) and served as a redox cycle.Positive interactions between Ce,W species and Fe oxide in red mud occurred,which led to the formation of unsaturated chemical bond and promoted the activation of adsorbed NH_(3) species.WO_(3) and Ce_(2)(WO_(4))_(3)(formed by solid-state reaction between Ce and W species)could provide more Brønsted acid sites(W-O modes of WO_(3),W=O or W-O-W modes of Ce_(2)(WO_(4))_(3)).CeO_(2) species could provide more Lewis acid sites.The Langmuir-Hinshelwood(L-H)routes and Eley-Rideal(E-R)routes occurred in the low-temperature SCR reaction on the Ce-W@RM surface.NH_(4)^(+) species on Brønsted acid sites,NH_(3) species on Lewis acid sites,bidentate nitrate and bridging nitrate species were key active intermediates species. 展开更多
关键词 Air pollution control NOx Selective catalytic reduction cerium TUNGSTEN
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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 被引量:1
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作者 Siow Ming Lee Christian Schulz Kumar Prabhash 《四川生理科学杂志》 2023年第8期1332-1332,共1页
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 pe... 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. 展开更多
关键词 PATIENTS platinum random
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Cerium Methacrylate Assisted Preparation of Highly Thermally Conductive and Anticorrosive Multifunctional Coatings for Heat Conduction Metals Protection
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作者 Fei Xu Peng Ye +7 位作者 Jianwen Peng Haolei Geng Yexiang Cui Di Bao Renjie Lu Hongyu Zhu Yanji Zhu Huaiyuan Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第11期172-184,共13页
Preparing polymeric coatings with well corrosion resistance and high thermal conductivity(TC)to prolong operational life and ensure service reliability of heat conductive metallic materials has long been a substantive... Preparing polymeric coatings with well corrosion resistance and high thermal conductivity(TC)to prolong operational life and ensure service reliability of heat conductive metallic materials has long been a substantive and urgent need while a difficult task.Here we report a multifunctional epoxy composite coating(F-CB/CEP)by synthesizing cerium methacrylate and ingeniously using it as a novel curing agent with corrosion inhibit for epoxy resin and modifier for boron nitride through"cation-π"interaction.The prepared F-CB/CEP coating presents a high TC of 4.29 W m^(−1)K^(−1),which is much higher than other reported anti-corrosion polymer coatings and thereby endowing metal materials coated by this coating with outstanding thermal management performance compared with those coated by pure epoxy coating.Meanwhile,the low-frequency impedance remains at 5.1×10^(11)Ωcm^(2)even after 181 days of immersion in 3.5 wt%NaCl solution.Besides,the coating also exhibits well hydrophobicity,self-cleaning properties,temperature resistance and adhesion.This work provides valuable insights for the preparation of high-performance composite coatings with potential to be used as advanced multifunctional thermal management materials,especially for heat conduction metals protection. 展开更多
关键词 Epoxy coatings Thermal conductivity ANTI-CORROSION HYDROPHOBICITY cerium methacrylate
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Cerium-promoted conversion of dinitrogen into high-energy-density material CeN_(6) under moderate pressure
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作者 Yuanyuan Wang Zhihui Li +4 位作者 Shifeng Niu Wencai Yi Shuang Liu Zhen Yao Bingbing Liu 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第3期55-64,共10页
Synthesis pressure and structural stability are two crucial factors for highly energetic materials,and recent investigations have indicated that cerium is an efficient catalyst for N2 reduction reactions.Here,we syste... Synthesis pressure and structural stability are two crucial factors for highly energetic materials,and recent investigations have indicated that cerium is an efficient catalyst for N2 reduction reactions.Here,we systematically explore Ce–N compounds through first-principles calculations,demonstrating that the cerium atom can weaken the strength of the N≡N bond and that a rich variety of cerium polynitrides can be formed under moderate pressure.Significantly,P1-CeN_(6) possesses the lowest synthesis pressure of 32 GPa among layered metal polynitrides owing to the strong ligand effect of cerium.The layered structure of P1-CeN_(6) proposed here consists of novel N_(14) ring.To clarify the formation mechanism of P1-CeN_(6),the reaction path Ce+3N2→trans-CeN_(6)→P1-CeN_(6) is proposed.In addition,P1-CeN_(6) possesses high hardness(20.73 GPa)and can be quenched to ambient conditions.Charge transfer between cerium atoms and N_(14) rings plays a crucial role in structural stability.Furthermore,the volumetric energy density(11.20 kJ/cm^(3))of P1-CeN_(6) is much larger than that of TNT(7.05 kJ/cm^(3)),and its detonation pressure(128.95 GPa)and detonation velocity(13.60 km/s)are respectively about seven times and twice those of TNT,and it is therefore a promising high-energy-density material. 展开更多
关键词 stability cerium
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Three-dimensional numerical simulation of heating and melting behaviors of cerium oxide powders in radio frequency thermal plasma
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作者 李雪迎 周志伟 +1 位作者 李容毅 朱海龙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第5期147-158,共12页
The present study aims at the numerical simulations of the melting process of cerium oxide particles in RF thermal plasma.The physical model and the calculating method were described firstly;the interaction between ce... The present study aims at the numerical simulations of the melting process of cerium oxide particles in RF thermal plasma.The physical model and the calculating method were described firstly;the interaction between cerium oxide particles and plasma was analyzed;specific attention was given to the effects of particle initial size,injection velocity on the particle melting and trajectory in plasma.The influence of the temperature field and velocity field distribution of the plasma around the particle trajectory on the melting effect is analyzed,and the relationship between the heat absorption efficiency of the particles and the particle size reduction process is further determined.It is also found that there exists an optimal particle initial injection velocity which led to a more concentrated final particle size distribution and a more significant reduction of particle size.The results could provide effective guidance for understanding the plasma spheroidization process of uranium dioxide and cerium dioxide powder particles. 展开更多
关键词 particle behaviors radio frequency thermal plasma SPHEROIDIZATION cerium oxide
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A Graphene-Based Aerogel Was Prepared as Solid Adsorbent for the Enrichment of Platinum (IV) at Trace Concentration
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作者 Lei Chen Han Diao +1 位作者 Qijiang Shu Tao Yang 《Advances in Materials Physics and Chemistry》 CAS 2023年第2期17-29,共13页
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 connecte... 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. 展开更多
关键词 GRAPHENE platinum (IV) AEROGEL Sample Preparation Three-Dimensional
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Cerium Oxide Nanoparticles Protect against Oxaliplatin Induced Testicular Damage: Biochemical, Histological, Immunohistochemical, and Genotoxic Study
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作者 Dalia M. Amin Marwa T. Abaza +2 位作者 Shimaa H. Ameen Ghada A. Elsammak Samar M. Reda 《Occupational Diseases and Environmental Medicine》 2023年第1期1-29,共29页
Oxaliplatin is a chemotherapeutic drug used for colorectal cancer treatment. The testicular toxic effect is one of its recorded toxicities which resulted in a few studies. Oxidative stress could be a direct cause of t... Oxaliplatin is a chemotherapeutic drug used for colorectal cancer treatment. The testicular toxic effect is one of its recorded toxicities which resulted in a few studies. Oxidative stress could be a direct cause of this testicular toxicity. Cerium oxide nanoparticles (CONPs) are optimistic antioxidants for applications in medicine. The aim of the work is to study the protective effect of CONPs on testicular toxicity induced by oxaliplatin in rats. Forty adult male albino rats were divided into 4 groups: Control group, CONPs group (60 mg/kg, 5 times/week), Oxaliplatin group (4 mg/kg, twice/week), and Oxaliplatin & CONPs group, for 4 weeks. Seventy-two hours after the last administration, blood samples were taken for hormonal levels and testes were used for both histopathology and immunohistochemical microscopic examination. Sperm smears were also performed and their results were statistically analyzed to detect any sperm abnormalities. Oxaliplatin increased MDA levels. SOD and GPx activity was decreased. GSH levels were decreased. Also, it decreased the sperm cell count and serum testosterone, and anti-Müllerian hormon. In the testicular sections, significant histopathology changes were seen and immunohistochemical examination confirmed these results. Upon supplementation of CONPs with oxaliplatin decreased MDA levels. SOD and GPx activity was increased, and GSH did not change. In testicular sections, normal morphology was seen. Also, there was an increase in the sperm cell count and serum testosterone anti-Müllerian with significant improvement of testicular architecture, and immunohistochemical examination confirmed these results. The utilization of CONPs produced significant protection against all of the above-mentioned changes. 展开更多
关键词 cerium Oxide Nanoparticles OXALIPLATIN Oxidative Stress TESTIS Toxicity
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Nano transdermal system combining mitochondria-targeting cerium oxide nanoparticles with all-trans retinoic acid for psoriasis
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作者 Wei Wang Xinyi Xu +4 位作者 Yanling Song Lan Lan Jun Wang Xinchang Xu Yongzhong Du 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第5期112-124,共13页
Psoriasis is an inflammatory skin disease that is intricately linked to oxidative stress.Antioxidation and inhibition of abnormal proliferation of keratinocytes are pivotal strategies for psoriasis.Delivering drugs wi... Psoriasis is an inflammatory skin disease that is intricately linked to oxidative stress.Antioxidation and inhibition of abnormal proliferation of keratinocytes are pivotal strategies for psoriasis.Delivering drugs with these effects to the site of skin lesions is a challenge that needs to be solved.Herein,we reported a nanotransdermal delivery system composed of all-trans retinoic acid(TRA),triphenylphosphine(TPP)-modified cerium oxide(CeO2)nanoparticles,flexible nanoliposomes and gels(TCeO_(2)-TRA-FNL-Gel).The results revealed that TCeO_(2)synthesized by the anti-micelle method,with a size of approximately 5 nm,possessed excellent mitochondrial targeting ability and valence conversion capability related to scavenging reactive oxygen species(ROS).TCeO_(2)-TRA-FNL prepared by the film dispersion method,with a size of approximately 70 nm,showed high drug encapsulation efficiency(>96%).TCeO_(2)-TRA-FNL-Gel further showed sustained drug release behaviors,great transdermal permeation ability,and greater skin retention than the free TRA.The results of in vitro EGF-induced and H2O2-induced models suggested that TCeO_(2)-TRA-FNL effectively reduced the level of inflammation and alleviated oxidative stress in HaCat cells.The results of in vivo imiquimod(IMQ)-induced model indicated that TCeO_(2)-TRA-FNL-Gel could greatly alleviate the psoriasis symptoms.In summary,the transdermal drug delivery system designed in this study has shown excellent therapeutic effects on psoriasis and is prospective for the safe and accurate therapy of psoriasis. 展开更多
关键词 PSORIASIS cerium oxide nanoparticles All-trans retinoic acid Flexible nanoliposomes Transdermal delivery
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Cooperative catalytic platinum species accelerating polysulfide redox reactions for Li-S batteries
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作者 Yujie Qi Ning Chai +7 位作者 Qinhua Gu Junnan Chen Zhaofeng Zhai Ming Lu Yiming Niu Nan Huang Xia Zhang Bingsen Zhang 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期123-135,I0005,共14页
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 fo... 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. 展开更多
关键词 Lithium-sulfur batteries platinum species N-doped carbon spheres Bidirectional catalysis Polysulfide conversion
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Interfacial engineering of holey platinum nanotubes for formic acid electrooxidation boosted water splitting
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作者 Zi-Xin Ge Yu Ding +6 位作者 Tian-Jiao Wang Feng Shi Pu-Jun Jin Pei Chen Bin He Shi-Bin Yin Yu Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期209-216,I0006,共9页
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 syn... 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. 展开更多
关键词 Holey platinum nanotubes Chemical functionalization Formic acid oxidation reaction Hydrogen evolution reaction Water splitting
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从铂化合物制备尾液中回收超细铂粉的研究
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作者 毕向光 王文思 +5 位作者 余泽锦 刘辉 冯丰 赵云昆 余建民 卿山 《贵金属》 CAS 北大核心 2024年第2期59-63,68,共6页
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... 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。 展开更多
关键词 铂类化合物 制备尾液 还原剂 超细铂粉
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石墨烯基介孔锰铈氧化物催化剂:制备和低温催化还原NO
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作者 王艳莉 钱心怡 +1 位作者 沈春银 詹亮 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第1期81-89,I0005,共10页
锰铈氧化物由于较强的氧化还原活性、优良的低温脱硝性能,已被广泛用于选择性催化还原(SCR)脱硝反应,但是锰铈氧化物存在活性组分易团聚、比表面积较低等问题,限制其催化剂活性的提高。本研究以介孔结构的石墨烯基SiO_(2)(G@SiO_(2))纳... 锰铈氧化物由于较强的氧化还原活性、优良的低温脱硝性能,已被广泛用于选择性催化还原(SCR)脱硝反应,但是锰铈氧化物存在活性组分易团聚、比表面积较低等问题,限制其催化剂活性的提高。本研究以介孔结构的石墨烯基SiO_(2)(G@SiO_(2))纳米材料为模板,采用水热法制备了系列石墨烯基介孔锰铈氧化物(G@MnO_(x)-CeO_(2))催化剂,并考察了该催化剂在低温下(100~300℃)的SCR脱硝性能。结果表明,与石墨烯基铈氧化物(G@CeO_(2))相比,G@MnO_(x)-CeO_(2)催化剂具有较高脱硝活性。当Mn、Ce与模板G@SiO_(2)质量比分别为0.35、0.90时,G@Mn(0.35)Ce(0.9)催化剂的脱硝活性最佳,220℃下NO转化率达到最高(80%)。添加适量MnO_(x),提高了G@MnO_(x)-CeO_(2)催化剂的比表面积、孔容,降低了催化剂的结晶度;并且MnO_(x)-CeO_(2)以纳米尺度(2~3 nm)较为均匀地分散于石墨烯片层表面。此外,由于MnO_(x)与CeO_(2)之间存在协同作用,Mn原子可以部分替代Ce原子掺杂于CeO_(2)的晶体结构中形成MnO_(x)-CeO_(2)固溶体,使G@Mn(0.35)Ce(0.9)催化剂表面存在较高含量的高价态Mn^(3+)和Mn^(4+)、Ce^(4+)以及较高的化学吸附氧浓度,从而展现出较高的脱硝性能。该工作为MnO_(x)-CeO_(2)基催化剂在低温NH3-SCR中的实际应用提供了基础数据。 展开更多
关键词 石墨烯 铈氧化物 锰氧化物 NO 选择性催化还原
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加热温度对工业规模CeCl_(3)喷雾焙烧反应器影响的数值模拟
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作者 董云芳 张松松 +3 位作者 王振峰 伍永福 刘中兴 刘铃声 《有色金属(冶炼部分)》 CAS 北大核心 2024年第6期85-96,共12页
CeO_(2)颗粒由于具有优异的性能,市场对CeO_(2)颗粒的需求逐年增加。为探究使用在氧化铁颗粒工业化生产的Ruthner型喷淋焙烧反应器生产CeO_(2)颗粒的可能性,结合单液滴失重试验,使用ANSYS Fluent软件,分别探究550、650、750和850℃四种... CeO_(2)颗粒由于具有优异的性能,市场对CeO_(2)颗粒的需求逐年增加。为探究使用在氧化铁颗粒工业化生产的Ruthner型喷淋焙烧反应器生产CeO_(2)颗粒的可能性,结合单液滴失重试验,使用ANSYS Fluent软件,分别探究550、650、750和850℃四种不同加热温度对反应器的影响。单液滴失重试验表明,氯化铈和氯化铁、氯化亚铁的热解过程基本一致,使用该型反应器制备CeO_(2)颗粒理论上可行。对小型工业反应器进行等比例建模,研究反应器内部化学反应的具体过程。结果表明,550℃是最合适的温度,对工业生产具有一定指导意义。 展开更多
关键词 氯化铈 喷雾热解 Ruthner型喷淋焙烧反应器 数值模拟
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喷雾热解法加热壁温对铈锆固溶体生产过程的影响
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作者 伍永福 栗志 +5 位作者 赵爽 刘中兴 王振峰 董云芳 刘玉宝 马守营 《中国粉体技术》 CAS CSCD 2024年第2期1-11,共11页
【目的】为了探究喷雾热解过程中加热壁温对铈锆固溶体生产过程的影响,分析热解炉内的流量场和浓度场的变化情况,实现对热解炉的设计优化。【方法】采用数值模拟的方法,建立喷雾热解炉的物理模型,分别探讨加热壁温对铈锆固溶体在热解炉... 【目的】为了探究喷雾热解过程中加热壁温对铈锆固溶体生产过程的影响,分析热解炉内的流量场和浓度场的变化情况,实现对热解炉的设计优化。【方法】采用数值模拟的方法,建立喷雾热解炉的物理模型,分别探讨加热壁温对铈锆固溶体在热解炉的不同阶段及热解炉中水蒸气分布和HCl分布的影响。【结果】当热解温度为850℃时,液滴的反应主要分2个阶段,在炉膛高度为0~0.05 m处,为加热蒸发阶段,在炉膛高度为0.05~0.6 m处,为稳态热解阶段。当炉壁温度为550~650℃时,在炉膛高度为0.9 m处温度变化放缓,喷雾处于稳定热解阶段;而壁温在750~850℃时,在炉膛高度为0.6 m处温度变化放缓;当壁温为850℃时,在炉膛高度为0.1~0.6 m处的温度曲线斜率最大,液滴达到稳定蒸发阶段的时间缩短,水分蒸发变快,热解时间变短。【结论】炉壁加热区的温度越高,HCl生成的速度越快,速度的最大值越小,在炉膛高度为0.4 m处速度变化最大,达到1.6 m/s左右;并且整体HCl生成的量随温度的升高而增大,平均速度变化随着热空气温度的升高而减小。 展开更多
关键词 喷雾热解 铈锆固溶体 稳态热解 稳定热解
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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
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作者 张晓欲 左金玲 +1 位作者 董娜 高淑凤 《中国性科学》 2024年第4期109-113,共5页
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,... 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。 展开更多
关键词 上皮性卵巢癌 铂类化疗 D-二聚体 血栓调节蛋白 化疗敏感性
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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
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作者 鲜亮 田小霞 +1 位作者 马婧 李伟 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2024年第3期137-146,共10页
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... 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。 展开更多
关键词 超细铂纳米颗粒 富勒烯 光化学法 降解p-硝基苯酚
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铂耐药卵巢癌复发现状及相关因素
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作者 刘建 廖宗敏 胡红波 《吉林医学》 CAS 2024年第5期1030-1033,共4页
目的:分析铂耐药卵巢癌复发现状及相关因素。方法:选取粤北人民医院2013年1月~2020年1月收治的86例复发性卵巢癌患者为研究对象,分为对照组(n=66)与观察组(n=20),单因素、多因素Logistic回归分析铂耐药卵巢癌复发的危险因素。结果:Logis... 目的:分析铂耐药卵巢癌复发现状及相关因素。方法:选取粤北人民医院2013年1月~2020年1月收治的86例复发性卵巢癌患者为研究对象,分为对照组(n=66)与观察组(n=20),单因素、多因素Logistic回归分析铂耐药卵巢癌复发的危险因素。结果:Logistic回归分析:脉管癌栓、初治时腹水量≥1000 ml、腹水有癌细胞、糖类抗原125(CA125)≥200 U/ml、FIGO分期、白蛋白(ALB)≤35 g/L、淋巴细胞与单核细胞比值(LMR)<5.12、血小板与淋巴细胞比值(PLR)≥124是卵巢癌复发的危险因素,差异有统计学意义(P<0.05)。结论:铂耐药卵巢癌复发与脉管癌栓、初治时腹水量、腹水有癌细胞、FIGO分期、人附睾蛋白4(HE4)、CA125、AIB、LMR、PLR异常等因素有关,应及早给予针对性处理,最大限度降低复发率。 展开更多
关键词 铂耐药 卵巢癌 复发 相关因素
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