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Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction media

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Chinese Journal of Chemistry 2024年第4期42卷 406-429页

作者： Csaba Árvai lászló T.mika Department of Chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial *** carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical ***,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction ***,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction *** this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVl),2-methyltetrahydrofuran(2-meTHF),ionic liquids(Ils),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： Carbonylation Catalysis Solvents Green chemistry Carbon monoxide Transition metals Homogeneous catalysis Palladium

Characteristics of Emission Non-nulling Pulsars Through Simulation

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Research in Astronomy and Astrophysics 2024年第4期24卷 91-102页

作者： rai Yuen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key laboratory of Radio Astrophysics Chinese Academy of SciencesUrumqi 830011China Key laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China SIfA School of PhysicsUniversity of SydneySydneyNSW2006Australia

We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar *** from a pulsar is identified as non-nulling if(i)the emission does not cease across the whole pulse profile,and(ii)the emission is ***(i),we adopt a model for switching in the plasma charge density,and emission persists if the charge density is ***(ii),we assume that detectable emission originates from source points where it is emitted tangentially to the magnetic field-line and parallel to the *** find that pulsars exhibiting non-nulling emission possess obliquity angles with an average of 42°.5,and almost half the samples maintain a duty cycle between 0.05 and ***,the pulsar population is not fixed but dependent on the obliquity angle,with the population peaking at 20°.In addition,three evolutionary phases are identified in the pulsar population as the obliquity angle evolves,with the majority of samples having an obliquity angle between 20°and 65°.Our results also suggest that emission from a pulsar may evolve between nulling and non-nulling during its lifetime.

关键词： radiation mechanisms:non thermal stars:neutron (stars:)pulsars:general

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： Ranjeet rai R.R.SAHOO mechanical Engineering Department GLA UniversityMathura281406India mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(l16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** l16 Orthogonal Array is obtained through Taguchi's experimental design approach using minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the l16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GRG HC CO and NO

Establishing the relationship between land use land cover,normalized difference vegetation index and land surface temperature:A case of lower Son River Basin,India

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Geography and Sustainability 2024年第2期5卷 265-275页

作者： Shipra Singh Pankaj Kumar Rakhi Parijat Barbaros Gonengcil Abhinav rai Department of Geography Miranda HouseUniversity of DelhiDelhiIndia Department of Geography Delhi School of EconomicsUniversity of DelhiDelhiIndia Department of Geography Istanbul UniversityIstanbulTurkey

The study explores the intricate interplay between land use land cover(lUlC),normalized difference vegetation index(NDVI),and land surface temperature(lST)within the lower Son River Basin in India from 1991 to *** region’s ecological balance has been increasingly strained due to rapid urbanization and changing land use *** a combination of landsat Tm&OlI/TIRS satellite imageries and geospatial analysis techniques,this study unveils the intricate connection between land use and land cover changes,vegetation,and land surface temperature *** study area is classified into three altitudinal zones(Zone I:39–300 m,Zone II:301–600 m and Zone III:601–1,247 m)to examine the changes in *** area has seen significant changes in lUlC,vegetation and lST in all the three altitudinal *** findings hold significant implications for sustainable land management and environmental conservation strategies in the lower Son River *** per the result,103,438 ha of vegetation was converted into agriculture land and 82,572 ha of agricultural land was transformed into settlements from 1991 to *** trend shows human pressure on the land resource in the study *** increase in water body is seen which is attributed to commissioning of Bansagar *** I has seen highest settlement growth while Zone III experienced severe deforestation of around 15%.Zone II and III needs attention for holistic *** of lST shows that it has increased by 0.82℃ from 1991 to 2020 which is a red *** study underscores the critical importance of balanced land use practices to preserve ecological integrity and mitigate the adverse effects of urbanization and climate change.

关键词： lower Son River Basin lUlC lST NDVI Correlation

Carbon monoxide as C1 Building Block in Fine Chemical Synthesis

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Chinese Journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.B.Carrilho mario J.F.Calvete Gabor mikle laszlo Kollar mariette m.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ElKH-PTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide Fine chemicals Carbonylation Hydroformylation C-H functionalization

multiplexed fluorescence and scatter detection with single cell resolution using on-chip fiber optics for droplet microfluidic applications

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microsystems & Nanoengineering 2024年第2期10卷 207-218页

作者： Preksha Gupta Ambili mohan Apurv mishra Atindra Nair Neeladri Chowdhury Dhanush Balekai Kavyashree rai Anil Prabhakar Taslimarif Saiyed Discovery Innovation Accelerator Centre for Cellular and Molecular PlatformsBellary RoadBengaluru560065KarnatakaIndia Department of Electrical Engineering Indian Institute of Technology MadrasChennai600036Tamil NaduIndia

Droplet microfluidics has emerged as a critical component of several high-throughput single-cell analysis techniques in biomedical research and *** significant progress in the development of individual assays,multiparametric optical sensing of droplets and their encapsulated contents has been *** current approaches,most commonly involving microscopy-based high-speed imaging of droplets,are technically complex and require expensive instrumentation,limiting their widespread *** address these limitations,we developed the OptiDrop platform;this platform is a novel optofluidic setup that leverages the principles of flow *** platform enables on-chip detection of the scatter and multiple fluorescence signals from the microfluidic droplets and their contents using optical *** highly customizable on-chip optical fiber-based signal detection system enables simplified,miniaturized,low-cost,multiparametric sensing of optical signals with high sensitivity and single-cell resolution within each *** demonstrate the ability of the OptiDrop platform,we conducted a differential expression analysis of the major histocompatibility complex(mHC)protein in response to IFNγ*** results showed the platform’s ability to sensitively detect cell surface biomarkers using fluorescently labeled ***,the OptiDrop platform combines the versatility of flow cytometry with the power of droplet microfluidics to provide wide-ranging,scalable optical sensing solutions for research and diagnostics.

关键词： scatter enable resolution

Spectrum of COVID-19 induced liver injury:A review report

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World Journal of Hepatology 2024年第4期16卷 517-536页

作者： lokjan Singh Anil Kumar maya rai Bibek Basnet Nishant rai Pukar Khanal Kok-Song lai Wan-Hee Cheng Ahmed morad Asaad Shamshul Ansari Department of microbiology Karnali Academy of Health ScienceTeaching HospitalJumla 21200KarnaliNepal Health Sciences Asian College of Advance StudiesPurbanchal UniversitySatdobato 24122LalitpurNepal Department of Biotechnology Graphic Era(Deemed to be University)Dehradun 248002UttarakhandIndia Department of Pharmacology&Toxicology KLE College of PharmacyBelagaviKLE Academy of Higher Education and ResearchBelagavi 590010KarnatakaIndia Division of Health Sciences Abu Dhabi Women's CollegeHigher Colleges of TechnologyAbu Dhabi 41012United Arab Emirates Health and life Sciences INTI International UniversityNilai 71800Malaysia Department of microbiology College of MedicineZagazig UniversityZagazig 44519Egypt

The coronavirus disease 2019(COVID-19)pandemic has caused changes in the global health system,causing significant setbacks in healthcare systems *** pandemic has also shown resilience,flexibility,and creativity in reacting to the *** severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection targets most of the respiratory tract,resulting in a severe sickness called acute respiratory distress syndrome that may be fatal in some *** the lung is the primary organ targeted by COVID-19 viruses,the clinical aspect of the disease is varied and ranges from asymptomatic to respiratory ***,due to an unorganized immune response and several affected mechanisms,the liver may also experience liver cell injury,ischemic liver dysfunction,and drug-induced liver injury,which can result in respiratory failure because of the immune system’s disordered response and other compromised processes that can end in multisystem organ *** with liver cirrhosis or those who have impaired immune systems may be more likely than other groups to experience worse results from the SARS-CoV-2 *** thus intend to examine the pathogenesis,current therapy,and consequences of liver damage concerning COVID-19.

关键词： Autoimmune liver disease COVID-19 Clinical manifestation of liver Drug-induced liver injury SARS-CoV-2

Effect of cold-working on corrosion induced damage in lug joints

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Defence Technology（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath m.N Chikmath l. murthy H. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

lug joints are preferred joineries for transferring heavy loads to parent components in aerospace *** experience corrosion due to environmental conditions,improper surface finishes and rubbing displacement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is modelled as a through-pit at one of the identified critical locations through stress *** effect of this pit on fatigue crack initiation life is ***-hole is pre-stressed by cold-working and the benefits of inducing plastic wake on the intended performance of the lug joint during the damages due to corrosion are brought out and compared with non-cold-worked *** analysis is performed on this lug joint with *** results obtained highlight the benefits of cold-working and the methodology can be extended to damage growth and analyse the effect of surface treatments for better structural integrity of components of aerospace vehicles.

关键词： lug joint Corrosion Crack initiation Cold-working Structural integrity

On calculating glacial isostatic adjustment

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Geodesy and Geodynamics 2024年第5期15卷 441-452页

作者： l.m.Cathles Cornell University

modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity profile. Here, we compare two methods for calculating the viscoelastic response to surface loading. In one, the elastic equation of motion is converted to a viscoelastic equation using the Correspondence Principle. In the other, elastic deformation is added to the viscous flow as isostatic adjustment proceeds. The two modeling methods predict adjustment histories that are different enough to potentially impact the interpretation of the observed glacial isostatic adjustment(GIA). The differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic pre-stress. The methods agree if they use the same equations and boundary conditions. The origin of the differences is determined by varying the boundary conditions and pre-stress application.

关键词： Correspondence principle Elastic buoyancy Glacial isostatic adjustment Hydrostatic pre-stress Viscoelastic normal modes