化学•材料最新文献

{"title":"How Isomer and Conformer Structures Impact Dissociation Dynamics of Alkane Radical Cations.","authors":"Madison K Minvielle, Mikaela Aftel, Timothy Hill, Hugo A López Peña, Katharine Moore Tibbetts","doi":"10.1021/acs.jpca.5c04290","DOIUrl":"https://doi.org/10.1021/acs.jpca.5c04290","url":null,"abstract":"<p><p>Ionization of alkanes to form radical cations activates their otherwise unreactive C-H bonds, facilitating important chemical processes such as hydrocarbon cracking. This work investigates the radical cation dissociation dynamics of hexane (C₆H₁₄) structural isomers by using femtosecond time-resolved mass spectrometry and quantum chemical calculations. All five isomers exhibit competition between the yields of fragment ions arising from direct C-C bond cleavage or dissociative rearrangement with hydrogen migration on dynamical time scales of ∼50-300 fs, suggesting that hydrogen migration in the metastable cations operates on such short time scales. Additional isomer- and conformer-specific dynamics are observed. Preferential dissociation pathways in the branched isomers are found to arise from geometric relaxation to cation structures with one elongated C-C bond. Coherent vibrational excitation along this elongated C-C bond in 3-methylpentane and 2,3-dimethylbutane results in ion yield oscillations in the first ∼300-400 fs after ionization. Enhanced depletion of the molecular ion signal in <i>n</i>-hexane compared to that in the branched isomers is attributed to a strongly coupled excited state in the most populated conformer that can be accessed by a two-photon transition. Collectively, these results provide a foundational understanding of dissociation dynamics in alkane radical cations and how these dynamics are affected by specific isomer and conformer structures.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145013522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Catalytic C-N Bond-Forming Processes from Inorganic Ammonium Salts.","authors":"Lan Tian,Hao-Ran Zhang,Yu-Long Li,Yu-Feng Ren,Wei Shu","doi":"10.1021/acs.joc.5c01676","DOIUrl":"https://doi.org/10.1021/acs.joc.5c01676","url":null,"abstract":"Catalytic C-N coupling reactions are among the most important bond-forming events in synthetic chemistry. Ammonium salts are economic and easily available inorganic compounds, serving as ideal nitrogen sources for nitrogen-containing organic compounds. The use of ammonium salts highlights the synthesis of N-containing organic compounds from inorganic compounds. Therefore, it is of great significance to develop catalytic methods for the C-N reaction from ammonium salts. This JOCSynopsis focuses on the representative processes of catalytic C-N bond formation from ammonium salts.","PeriodicalId":57,"journal":{"name":"Journal of Organic Chemistry","volume":"31 1","pages":""},"PeriodicalIF":4.354,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145008843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of renewable energy-based products application for battery thermal management","authors":"Farbod Esmaeilion ,&nbsp;Siamak Hoseinzadeh ,&nbsp;Safiye Shafiei ,&nbsp;Ebrahim Pilali ,&nbsp;Alireza Taklifi ,&nbsp;M. Soltani ,&nbsp;Davide Astiaso Garcia","doi":"10.1016/j.rser.2025.116247","DOIUrl":"10.1016/j.rser.2025.116247","url":null,"abstract":"<div><div>Battery overheating can have detrimental effects on battery performance, safety, longevity, and environmental sustainability. Implementing effective thermal management strategies and safety measures to prevent overheating and ensure the safe and reliable operation of batteries in numerous applications is decisive. Reduced battery lifespan, safety hazards, performance degradation, loss of functionality, environmental impacts, and costs of replacement or repair are the detrimental impacts of battery operation in electric cars, renewable energy storage facilities, consumer appliances, and grid-scale energy storage systems. Renewable energy-based products can be effectively utilized for Battery Thermal Management Systems (BTMS) in several ways, confirming the ideal performance, longevity, and protection of batteries. The analysis demonstrates that renewable-integrated BTMS reduced peak battery temperatures by up to 15 °C, significantly lowering the risk of thermal runaway and extending battery lifespan. Solar-powered ventilation systems decreased cooling energy consumption by nearly 70 % compared with conventional methods, while biomass-driven PCMs maintained battery temperatures below 60 °C under high C-rate discharges. By integrating renewable energy-based products for BTMS, such as solar-powered ventilation systems, geothermal cooling technologies, wind-powered ventilation/cooling systems, hydroelectric facilities, and biomass energy-driven systems, the integration of renewable energy-based products enables maintainable and systematic operation of battery systems while dropping dependence on non-renewable energy resources and diminishing environmental influence. Geothermal-PVT hybrid systems improved overall energy efficiency by 53 % and decreased total energy consumption by 25.7 %, whereas hydrogen-based cooling stabilized battery temperatures below 30.5 °C with thermal gradients under 7 °C. Hybrid RES–BTMS configurations reduced the levelized cost of energy to 0.094 USD/kWh and lowered greenhouse gas emissions by up to 3.5 million kg CO₂ annually, indicating substantial environmental and economic benefits. The identified trend provides a practical pathway to attain the required specifications for environmentally benign, economic, and efficient performance. The proposed concept of renewable-energy-based BTMS enables electricity, material, and fuel production as a solution for future operations in the BTMS. A comprehensive examination of the concept has been presented in the review.</div></div>","PeriodicalId":418,"journal":{"name":"Renewable and Sustainable Energy Reviews","volume":"226 ","pages":"Article 116247"},"PeriodicalIF":16.3,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145007630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A CuBi2O4/TiO2 p–n Heterojunction for Enhancing the Barrier Protection of a Nickel-Based Layer on the Magnesium Alloy","authors":"Yu Wen, Yanghua Teng, Yue Liu, Xiaoqiang Fan, Liang Wu, Zhi-Hui Xie","doi":"10.1021/acs.jpclett.5c02258","DOIUrl":"https://doi.org/10.1021/acs.jpclett.5c02258","url":null,"abstract":"Herein, CuBi₂O₄ microspheres were first deposited on TiO₂ nanotube arrays to develop a p–n CuBi₂O₄/TiO₂ heterojunction by a facile hydrothermal protocol. The variations in the photoinduced open-circuit potential, photocurrent, and electrochemical parameters of the nickel-plated magnesium alloy (Mg/Ni) demonstrated the remarkably strengthened photoelectrochemical efficiency and photocathodic protection (PCP) capability caused by the CuBi₂O₄ modification. This enhancement is attributed to establishing a built-in electric field and intensified light absorption in a broadened wavelength spectrum, confirmed by the valence band XPS and ultraviolet–visible spectra. The as-prepared photoanode showed an unprecedentedly high photocurrent density compared with that of current heterojunctions based on CuBi₂O₄ and TiO₂ semiconductors. The heterojunction continuously provided PCP to the Mg/Ni couple and suppressed the galvanic corrosion between the Mg and nickel–phosphorus alloy. This study proposed a new strategy for constructing a heterojunction with a novel morphology and considerably enhanced photoelectrochemical performance.","PeriodicalId":62,"journal":{"name":"The Journal of Physical Chemistry Letters","volume":"40 1","pages":""},"PeriodicalIF":6.475,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145007157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electron Pushing: Variants That Alter the Catalytic Distribution of Electrons in Dihydroorotate Dehydrogenase 1B from <i>Lactococcus lactis</i>.","authors":"Corine O Smith, Richa Khatiwada, Pengfei Li, Graham R Moran","doi":"10.1021/acs.biochem.5c00409","DOIUrl":"https://doi.org/10.1021/acs.biochem.5c00409","url":null,"abstract":"<p><p>Dihydroorotate dehydrogenase 1B (DHOD1B) is one of several flavoproteins that utilize active half-sites. These enzymes have two flavin cofactors (FAD and FMN) that each interact with a specific reductant/oxidant substrate/product. Electrons gained at one-half-site must be transmitted to the other half-site and iron-sulfur centers between the flavin cofactors serve in this role. DHOD1B from <i>Lactococcus lactis</i> (LlDHOD1B) is a heterodimeric protein that has been shown to fractionally accumulate a flavin bisemiquinone state comprised of equimolar anionic and neutral forms, demonstrating an internal electron distribution equilibrium. Variant forms of LlDHOD1B were designed to perturb predicted or claimed pathways for internal transmission of electrons. Lysine 48 of the PyrD subunit is positioned near the FMN isoalloxazine N5 and the orotate C6-carboxylate. The K48M variant revealed that the anionic semiquinone resides at the FMN cofactor and that the lysine's role is electrostatic, influencing both the p<i>K</i>_a and reduction potential of the FMN. Glutamate 221 of the PyrK subunit stacks with the FAD isoalloxazine. The E221Q variant established that this charge influences the rate of hydride transfer from NADH and the rate of reduction of orotate and accumulates little of the flavin bisemiquinone observed with the WT enzyme. Cysteine 135 of the PyrD subunit serves as the active half-site acid/base. The C135A variant prevented reduction of orotate, permitting the influence of orotate binding on the reduction potential of the FMN cofactor to be determined indicating a +70 mV change in the FMN reduction potential with the association of orotate.</p>","PeriodicalId":28,"journal":{"name":"Biochemistry Biochemistry","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145013452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rice Husk-Derived Silicon Carbide Mixed-Matrix Membranes for Enhanced Oil-Water Emulsion Separation.","authors":"Bakdash Rashed S, Chanbasha Basheer, Aljundi Isam H","doi":"10.1002/asia.202500390","DOIUrl":"https://doi.org/10.1002/asia.202500390","url":null,"abstract":"<p><p>In this study, a silicon carbide (SiC) mixed-matrix membrane for oil-water separation was successfully fabricated within the nanofiltration range. Silicon carbide was synthesized using rice husk ash (RHA), an agricultural waste material, combined with polydimethylsiloxane (PDMS) and subsequently incorporated into a mixed matrix membrane for oil-water separation. Polysulfone (PSF) and polyvinylpyrrolidone (PVP) were employed as polymer supports for fabricating the SiC-based mixed matrix membrane, which was tested in a dead-end filtration setup. The synthesized SiC and mixed matrix membrane were characterized using SEM-EDX, XPS, TGA, and Raman spectroscopy to evaluate their chemical and physical properties. Key operational parameters, including applied pressure, oil concentration, and membrane composition, were systematically optimized to enhance rejection efficiency. The functionalized SiC membrane exhibited outstanding performance, achieving up to 96% oil rejection at an oil concentration of 500 mg L^-1 and a pressure of 2 bar, with a contact angle of 36°, outperforming previously reported conventional commercial SiC-based mixed matrix membranes.</p>","PeriodicalId":145,"journal":{"name":"Chemistry - An Asian Journal","volume":" ","pages":"e00390"},"PeriodicalIF":3.3,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145013505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ssDNA and ssRNA Promote Phase Condensation of SAMHD1.","authors":"Brandon E Smith, Ankita Pohnerkar, Benjamin Orris, Shridhar Bhat, Matthew Egleston, James T Stivers","doi":"10.1021/acs.biochem.5c00422","DOIUrl":"https://doi.org/10.1021/acs.biochem.5c00422","url":null,"abstract":"<p><p>SAMHD1 (SAM domain and HD domain-containing protein 1) is a deoxynucleoside triphosphate triphosphohydrolase (dNTPase) with functions in viral restriction, R-loop resolution, DNA repair, telomere maintenance, ssRNA homeostasis, and regulation of self-nucleic acids. As a dNTPase, SAMHD1 functions as an allosterically activated tetramer, where binding of GTP to the A1 activator site of each monomer initiates dNTP-dependent tetramerization. cEM structures reveal that the nucleic-acid-related functions of SAMHD1 involve binding of guanine residues to the A1 site, leading to oligomeric forms that appear as beads-on-a-string on single-stranded RNA and DNA. SAMHD1's cellular activities and known protein interactions involve liquid-liquid phase separation (LLPS), although there are no reports that SAMHD1 itself exhibits phase separation properties. The protein phase separation prediction algorithm MolPhase indicated an overall phase separation probability score of 0.65 and suggested that the amino terminal SAM domain and the disordered carboxyl terminus (CT) may promote phase separation. Although no phase separation behavior was observed in physiological buffer, in the presence of 9% PEG 2000 and ssDNA or ssRNA, SAMHD1 condensed into liquid-like droplets. These droplets were disrupted by deletion of the SAM or CT domains, showed fusion behavior, and were rapidly disrupted by the addition of A1 site ligands GTP, dGTP, and small-molecule inhibitors. We also observed that SAMHD1-ssDNA condensates within the nuclei of human cells in microinjection experiments, supporting a biological relevance for such complexes. LLPS by SAMHD1 could serve a regulatory role in cells and provide a new therapeutic target for the treatment of cancer and viral infections.</p>","PeriodicalId":28,"journal":{"name":"Biochemistry Biochemistry","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145005676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microplastic Diversity as a Potential Driver of Soil Denitrification Shifts.","authors":"Tian-Gui Cai,Da Lin,Bang Ni,Tian-Lun Zhang,Yi-Fei Wang,Dong Zhu","doi":"10.1021/acs.est.5c04981","DOIUrl":"https://doi.org/10.1021/acs.est.5c04981","url":null,"abstract":"Microplastics (MPs) are raising significant global concerns due to their environmental impacts. While most studies have focused on the effects of individual MP types, MPs in natural environments typically coexist as multiple types, and their combined effects remain poorly understood. In this study, we conducted a microcosm experiment with four levels of MP diversity (0, 1, 3, and 5 types) to investigate the effects of MP diversity on soil ecosystem functions using metagenomic sequencing. Our results revealed that increasing MP diversity significantly raised soil pH and organic carbon content while reducing available nitrogen. Notably, bacterial alpha diversity (Shannon and Invsimpson indices) increased significantly with higher MP diversity. Moreover, increasing MP diversity markedly shifted bacterial life-history strategies to adapt to the altered environment. Importantly, the abundance of nitrogen-related functional genes also increased with MP diversity. In particular, the abundance of denitrifying genes, predominantly driven by Rhodocyclaceae, was notably enhanced, resulting in a reduction of soil available nitrogen. Collectively, these findings offer valuable insights into the impact of MP diversity on soil function─especially within the nitrogen cycle─and have important implications for soil management strategies under MP stress.","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":"25 1","pages":""},"PeriodicalIF":9.028,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strong Metal-Support Interactions in Catalytic Oxidation of VOCs: Mechanistic Insights, Support Engineering Strategies, and Emerging Catalyst Design Paradigms.","authors":"Ziyue Jiang,Yongtao Li,Ziyu Tang,Dingkun Yuan,Fawei Lin","doi":"10.1021/acs.est.5c09511","DOIUrl":"https://doi.org/10.1021/acs.est.5c09511","url":null,"abstract":"Volatile organic compounds (VOCs) significantly impact air quality as photochemical smog precursors and health hazards. Catalytic oxidation is a leading VOC abatement method but suffers from catalyst deactivation due to metal sintering and competitive adsorption in complex mixtures. Strong metal-support interactions (SMSIs) provide atomic level control of interfacial electronic and geometric structures. SMSI enables bidirectional charge transfer, d band center modulation, oxygen vacancy generation, and tunable encapsulation that together promote O2 activation, lower barriers, and impart thermal and chemical robustness. This review synthesizes mechanistic insights and recent progress in SMSI-enabled VOC oxidation, integrating in situ and operando probes with kinetics. Reactivity and selectivity across aromatics, alkanes, oxygenates, and chlorinated species are rationalized by SMSI-mediated tuning of adsorption and intermediate evolution. Practical levers include control of particle size and dispersion, core-shell architectures, metal loading, and support acidity or basicity. Emerging directions include single atom catalysts, high entropy alloys, and nonmetal supports. Key challenges concern the dynamic evolution of SMSI under realistic feeds and the scalable, reproducible synthesis of interfaces. Future developments combining in situ characterization with data-driven catalyst design hold promise for achieving durable, high-performance VOC abatement with reduced precious metal usage.","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":"16 1","pages":""},"PeriodicalIF":9.028,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanistic and Kinetic Insights into Nitrogen Chemistry: NH₂-Mediated H-Abstraction and HCN Addition Pathways in NH₃/Ethanol Combustion.","authors":"Tong Yan, Pan Wang, Jianmin Liu, Jinsheng Zhang, Lidong Zhang","doi":"10.1021/acs.jpca.5c03451","DOIUrl":"https://doi.org/10.1021/acs.jpca.5c03451","url":null,"abstract":"<p><p>To elucidate possible mechanisms of nitrogen chemistry between ammonia (NH₃) and ethanol, the potential pathways of ethanol radicals (Wa, Wb, and Wc) following H-abstraction by NH₂ radicals were primarily investigated including HCN addition, H-transfer, and dissociation reactions by quantum chemical calculations. The rate constants were solved in the master equation based on RRKM and TST theory and fitted to the Arrhenius equation. The results demonstrate that H-abstraction from C₂H₅OH by NH₂ at the b-site is the most competitive, facilitating subsequent HCN addition. The HCN addition-entranced channel exhibits a negative temperature coefficient (NTC) behavior at 0.01 atm, and the onset of this effect is progressively delayed with pressure. The low-temperature reaction path of ethanol radicals with HCN is dominated by the initial adduct (WaHCN, WbHCN, and WcHCN) formation and subsequent isomerization. The multiple dissociation product channels become more competitive with temperature, especially the HCNH elimination. Findings from this study identify new growth pathways for NPAHs and OPAHs in the reaction of straight-chain molecules with HCN and provide comprehensive kinetic insights.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145008039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}