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古汉语中的合体字与英语中的Compound Word和Derivative Word浅析 被引量:1
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作者 李新新 李克莉 《青海师范大学民族师范学院学报》 2005年第2期25-26,共2页
传统观念认为,英语的"word"与汉语的“词”是一个概念,可是若对英语"word"和汉语中的“字”进行详细分析,我们不难发现,在大多数情况下,说英语的人谈到"word"的场合,说汉语的人说到的就是“字”,也就是说... 传统观念认为,英语的"word"与汉语的“词”是一个概念,可是若对英语"word"和汉语中的“字”进行详细分析,我们不难发现,在大多数情况下,说英语的人谈到"word"的场合,说汉语的人说到的就是“字”,也就是说,“word'’与汉语中的“字”也有多方面说清道不明的联系,有异曲同工之处。尤其是对古代汉“字”的特点去分析之后,更能说明这一点。本文试图通过对古汉“字”与英语中的 compound word和derivative word的分析比较,粗浅地谈一些不成熟的见解。 展开更多
关键词 古汉语 合体字 COMPOUND word和derivative word
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Organic solar cells with D18 or derivatives offer efficiency over 19%
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作者 Erming Feng Chujun Zhang +3 位作者 Jianhui Chang Hengyue Li Liming Ding Junliang Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第5期1-4,共4页
In recent years,organic solar cells(OSCs)have garnered significant attention due to their distinctive attributes,such as flexibility,lightweight,and solution processing,which position them as alternatives for next-gen... In recent years,organic solar cells(OSCs)have garnered significant attention due to their distinctive attributes,such as flexibility,lightweight,and solution processing,which position them as alternatives for next-generation solar technologies[1−5].Thanks to breakthroughs in materials development,the power conversion efficiency(PCE)for single-junction OSCs has already surpassed 19%[6−13].The development of photoactive materials is pivotal in enhancing the PCEs,and several reviews have provided insights into materials design[14−18].Herein,we highlight single-junction OSCs based on D18 and its derivatives[19,20]. 展开更多
关键词 BREAKTHROUGH INSIGHT derivativeS
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Fullerenes and derivatives as electrocatalysts: Promises and challenges
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作者 Kun Guo Ning Li +1 位作者 Lipiao Bao Xing Lu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期7-27,共21页
Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion technologies.Of paramount significance are the establishment of design princi... Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion technologies.Of paramount significance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active sites.Distinct from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis community.For instance,the well-defined atomic and molecular structures,the good electron affinity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modification have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon ma-terials.As increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent progress.This review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its derivatives.The content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deficiencies of these fullerene-based materials are explicitly elaborated.We conclude it by sharing our perspectives on the key aspects that future efforts shall consider. 展开更多
关键词 FULLERENE Fullerene derivative Metal-free catalyst Structural defect ELECTROCATALYST
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Discovery and structure-activity relationship studies of novel tetrahydro-β-carboline derivatives as apoptosis initiators for treating bacterial infections
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作者 Shanshan Su Hongwu Liu +7 位作者 Junrong Zhang Puying Qi Yue Ding Ling Zhang Linli Yang Liwei Liu Xiang Zhou Song Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1259-1273,共15页
Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a... Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a new type of1,2,3,4-tetrahydro-β-carboline(THC)derivatives and evaluated the in vitro and in vivo bioactivities against the Xanthomonas oryzae pv.oryzae(Xoo),Xanthomonas axonopodis pv.citri(Xac),and Pseudomonas syringae pv.actinidiae(Psa).The in vitro bioassay results exhibited that most title molecules possessed good activity toward the three plant pathogenic bacteria,the compound A17 showed the most active against Xoo and Xac with EC50 values of 7.27 and 4.89 mg mL^(-1)respectively,and compound A8 exhibited the best inhibitory activity against Psa with EC50value of 4.87 mg mL^(-1).Pot experiments showed that compound A17 exhibited excellent in vivo antibacterial activities to manage rice bacterial leaf blight and citrus bacterial canker,with protective efficiencies of 52.67 and 79.79%at 200 mgmL^(-1),respectively.Meanwhile,compound A8 showed good control efficiency(84.31%)against kiwifruit bacterial canker at 200 mg mL^(-1).Antibacterial mechanism suggested that these compounds could interfere with the balance of the redox system,damage the cell membrane,and induce the apoptosis of Xoo cells.Taken together,our study revealed that tetrahydro-β-carboline derivatives could be a promising candidate model for novel broadspectrum bactericides. 展开更多
关键词 tetrahydro-β-carboline derivatives antibacterial activity ROS cell apoptosis
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Development and identification of two novel wheat-rye 6R derivative lines with adult-plant resistance to powdery mildew and high-yielding potential
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作者 Guohao Han Jing Wang +10 位作者 Hanwen Yan Tiantian Gu Lijun Cao Shiyu Liu Xiuquan Li Yilin Zhou Jieru Fan Zhipeng Shi Hong Liu Lihui Li Diaoguo An 《The Crop Journal》 SCIE CSCD 2024年第1期308-313,共6页
Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared wit... Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared with the resistance genes from common wheat,alien resistance genes can better withstand infection of this highly variable pathogen.Development of elite alien germplasm resources with powdery mildew resistance and other key breeding traits is an attractive strategy in wheat breeding.In this study,three wheat-rye germplasm lines YT4-1,YT4-2,and YT4-3 were developed through hybridization between octoploid triticale and common wheat,out of which the lines YT4-1 and YT4-2 conferred adult-plant resistance(APR)to powdery mildew while the line YT4-3 was susceptible to powdery mildew during all of its growth stages.Using genomic in situ hybridization,multi-color fluorescence in situ hybridization,multi-color GISH,and molecular marker analysis,YT4-1,YT4-2,and YT4-3 were shown to be cytogenetically stable wheat-rye 6R addition and T1RS.1BL translocation line,6RL ditelosomic addition and T1RS.1BL translocation line,and T1RS.1BL translocation line,respectively.Compared with previously reported wheat-rye derivative lines carrying chromosome 6R,YT4-1 and YT4-2 showed stable APR without undesirable pleiotropic effects on agronomic traits.Therefore,these novel wheat-rye 6R derivative lines are expected to be promising bridge resources in wheat disease breeding. 展开更多
关键词 Powdery mildew Secale cereale Triticum aestivum Wheat-rye 6R derivatives Agronomic performance
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Identification of key genes regulating the synthesis of quercetin derivatives in Rosa roxburghii through integrated transcriptomics and metabolomics
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作者 Liyao Su Min Wu +2 位作者 Tian Zhang Yan Zhong Zongming(Max) Cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期876-887,共12页
Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five differ... Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five different stages of R. roxburghii fruit development. Flavonoids and the genes related to their biosynthesis were found to undergo significant changes in abundance across different developmental stages, and numerous quercetin derivatives were identified. We found three gene expression modules that were significantly associated with the abundances of the different flavonoids in R. roxburghii and identified three structural UDP-glycosyltransferase genes directly involved in the synthesis of quercetin derivatives within these modules. In addition, we found that RrBEH4, RrLBD1 and RrPIF8could significantly increase the expression of downstream quercetin derivative biosynthesis genes. Taken together,these results provide new insights into the metabolism of flavonoids and the accumulation of quercetin derivatives in R. roxburghii. 展开更多
关键词 Rosa roxburghii quercetin derivatives weighted gene co-expression network analysis transcription factor transcriptome METABOLOME
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High-Value-Added Utilization of Turpentine:Screening of Anti-Influenza Virus Agents fromβ-Pinene Derivatives
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作者 Yiwen Li Hongyan Si +7 位作者 Peng Wang Hai Luo Minggui Shen Xiaoping Rao Zhanqian Song Shibin Shang Zongde Wang Shengliang Liao 《Journal of Renewable Materials》 EI CAS 2024年第1期45-56,共12页
Turpentine is a renewable and resourceful forest product.The deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread attention.This study aimed to synthesize 4... Turpentine is a renewable and resourceful forest product.The deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread attention.This study aimed to synthesize 40 derivatives ofβ-pinene,including nopinone,3-cyanopyridines of nopinone,myrtanyl acid,myrtanyl acylthioureas,and myrtanyl amides.We assessed the antiviral activities of theseβ-pinene derivatives against influenza virus A/Puerto Rico/8/34(H1N1)using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.Theβ-pinene derivatives were used before and after cellular infection with the influenza virus to evaluate their preventive and therapeutic effects against the H1N1 virus.The results showed that only compound 10o exhibited a preventive effect against the H1N1 virus with a half-maximal inhibitory concentration(IC50)value of 47.6μmol/L.Among the compounds,4e,4i,and 4l demonstrated therapeutic effects against cellular infection,with compound 4e displaying the most potent therapeutic effect(IC50=17.5μmol/L),comparable to the positive control ribavirin.These findings indicated that certainβ-pinene derivatives exhibited in vitro antiviral activity against the H1N1 influenza A virus,warranting further investigation as potential anti-influenza agents. 展开更多
关键词 Antiviral activity Β-PINENE derivative 3-CYANOPYRIDINE influenza virus
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Sepsis Prediction Using CNNBDLSTM and Temporal Derivatives Feature Extraction in the IoTMedical Environment
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作者 Sapiah Sakri Shakila Basheer +4 位作者 Zuhaira Muhammad Zain Nurul Halimatul Asmak Ismail Dua’Abdellatef Nassar Manal Abdullah Alohali Mais Ayman Alharaki 《Computers, Materials & Continua》 SCIE EI 2024年第4期1157-1185,共29页
Background:Sepsis,a potentially fatal inflammatory disease triggered by infection,carries significant healthimplications worldwide.Timely detection is crucial as sepsis can rapidly escalate if left undetected.Recentad... Background:Sepsis,a potentially fatal inflammatory disease triggered by infection,carries significant healthimplications worldwide.Timely detection is crucial as sepsis can rapidly escalate if left undetected.Recentadvancements in deep learning(DL)offer powerful tools to address this challenge.Aim:Thus,this study proposeda hybrid CNNBDLSTM,a combination of a convolutional neural network(CNN)with a bi-directional long shorttermmemory(BDLSTM)model to predict sepsis onset.Implementing the proposed model provides a robustframework that capitalizes on the complementary strengths of both architectures,resulting in more accurate andtimelier predictions.Method:The sepsis prediction method proposed here utilizes temporal feature extraction todelineate six distinct time frames before the onset of sepsis.These time frames adhere to the sepsis-3 standardrequirement,which incorporates 12-h observation windows preceding sepsis onset.All models were trained usingthe Medical Information Mart for Intensive Care III(MIMIC-III)dataset,which sourced 61,522 patients with 40clinical variables obtained from the IoT medical environment.The confusion matrix,the area under the receiveroperating characteristic curve(AUCROC)curve,the accuracy,the precision,the F1-score,and the recall weredeployed to evaluate themodels.Result:The CNNBDLSTMmodel demonstrated superior performance comparedto the benchmark and other models,achieving an AUCROC of 99.74%and an accuracy of 99.15%one hour beforesepsis onset.These results indicate that the CNNBDLSTM model is highly effective in predicting sepsis onset,particularly within a close proximity of one hour.Implication:The results could assist practitioners in increasingthe potential survival of the patient one hour before sepsis onset. 展开更多
关键词 Temporal derivatives hybrid deep learning predicting sepsis onset MIMIC III machine learning(ML) deep learning
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Laboratory Implementation of Direct Torque Controller based Speed Loop Pseudo Derivative Feedforward Controller for PMSM Drive
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作者 Prabhakaran Koothu Kesavan Umashankar Subramaniam Dhafer J.Almakhles 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期12-21,共10页
This paper,evaluate the effectiveness of a proposed speed loop pseudo derivative feedforward(PDFF)controller-based direct torque controller(DTC)for a PMSM drive against the performance of existing PI speed controller-... This paper,evaluate the effectiveness of a proposed speed loop pseudo derivative feedforward(PDFF)controller-based direct torque controller(DTC)for a PMSM drive against the performance of existing PI speed controller-based DTC and hysteresis current controller(HCC).The proposed PDFF-based speed regulator effectively reduces oscillation and overshoot associated with rotor angular speed,electromagnetic torque,and stator current.Two case studies,one using forward-to-reverse motoring operation and the other involving reverse-to-forward braking operation,has been validated to show the effectiveness of the proposed control strategy.The proposed controller's superior performance is demonstrated through experimental verification utilizing an FPGA controller for a 1.5 kW PMSM drive laboratory prototype. 展开更多
关键词 Direct torque control Pseudo derivative feedforward controller Permanent magnet synchronous motor(PMSM)
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Applications of Metal–Organic Frameworks and Their Derivatives in Electrochemical CO_(2)Reduction 被引量:2
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作者 Chengbo Li Yuan Ji +8 位作者 Youpeng Wang Chunxiao Liu Zhaoyang Chen Jialin Tang Yawei Hong Xu Li Tingting Zheng Qiu Jiang Chuan Xia 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第8期72-115,共44页
Electrochemically reducing CO_(2)to more reduced chemical species is a promising way that not only enables the conversion of intermittent energy resources to stable fuels,but also helps to build a closed-loop anthropo... Electrochemically reducing CO_(2)to more reduced chemical species is a promising way that not only enables the conversion of intermittent energy resources to stable fuels,but also helps to build a closed-loop anthropogenic carbon cycle.Among various electrocatalysts for electrochemical CO_(2)reduction,multifunctional metal–organic frameworks(MOFs)have been employed as highly efficient and selective heterogeneous electrocatalysts due to their ultrahigh porosity and topologically diverse structures.Up to now,great progress has been achieved in the design and synthesis of highly active and selective MOF-related catalysts for electrochemical CO_(2)reduction reaction(CO_(2)RR),and their corresponding reaction mechanisms have been thoroughly studied.In this review,we summarize the recent progress of applying MOFs and their derivatives in CO_(2)RR,with a focus on the design strategies for electrocatalysts and electrolyzers.We first discussed the reaction mechanisms for different CO_(2)RR products and introduced the commonly applied electrolyzer configurations in the current CO_(2)RR system.Then,an overview of several categories of products(CO,HCOOH,CH_(4),CH_(3)OH,and multi-carbon chemicals)generated from MOFs or their derivatives via CO_(2)RR was discussed.Finally,we offer some insights and perspectives for the future development of MOFs and their derivatives in electrochemical CO_(2)reduction.We aim to provide new insights into this field and further guide future research for large-scale applications. 展开更多
关键词 Metal-organic frameworks derivativeS CATALYST CO_(2)reduction reaction ELECTROCATALYSIS
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Advances and challenges in using nirmatrelvir and its derivatives against SARS-CoV-2 infection 被引量:1
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作者 Wujun Chen Bing Liang +3 位作者 Xiaolin Wu Ling Li Chao Wang Dongming Xing 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第3期255-261,共7页
On December 22,2021,the United States Food and Drug Administration approved the first main protease inhibitor,i.e.,oral antiviral nirmatrelvir(PF-07321332)/ritonavir(Paxlovid),for the treatment of early severe acute r... On December 22,2021,the United States Food and Drug Administration approved the first main protease inhibitor,i.e.,oral antiviral nirmatrelvir(PF-07321332)/ritonavir(Paxlovid),for the treatment of early severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.Nirmatrelvir inhibits SARSCoV-2 infection,but high doses or long-term treatment may cause embryonic developmental toxicity and changes in host gene expression.The chiral structure of nirmatrelvir plays a key role in its antiviral activity.Ritonavir boosts the efficacy of nirmatrelvir by inactivating cytochrome P4503A4 expression and occupying the plasma protein binding sites.Multidrug resistance protein 1 inhibitors may increase the efficacy of nirmatrelvir.However,Paxlovid has many contraindications.Some patients treated with Paxlovid experience a second round of coronavirus disease 2019(COVID-19)symptoms soon after recovery.Interestingly,the antiviral activity of nirmatrelvir metabolites,such as compounds 12e18,is similar to or higher than that of nirmatrelvir.Herein,we review the advances and challenges in using nirmatrelvir and its derivatives with the aim of providing knowledge for drug developers and physicians in the fight against COVID-19. 展开更多
关键词 Nirmatrelvir PHARMACOLOGY PHARMACOKINETICS TOXICOLOGY derivativeS COVID-19
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Study of Fractional Order Dynamical System of Viral Infection Disease under Piecewise Derivative 被引量:1
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作者 Kamal Shah Hafsa Naz +1 位作者 Thabet Abdeljawad Bahaaeldin Abdalla 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期921-941,共21页
This research aims to understand the fractional order dynamics of the deadly Nipah virus(NiV)disease.We focus on using piecewise derivatives in the context of classical and singular kernels of power operators in the C... This research aims to understand the fractional order dynamics of the deadly Nipah virus(NiV)disease.We focus on using piecewise derivatives in the context of classical and singular kernels of power operators in the Caputo sense to investigate the crossover behavior of the considered dynamical system.We establish some qualitative results about the existence and uniqueness of the solution to the proposed problem.By utilizing the Newtonian polynomials interpolation technique,we recall a powerful algorithm to interpret the numerical findings for the aforesaid model.Here,we remark that the said viral infection is caused by an RNA type virus which can transmit from animals and also from an infected person to person.Fruits bats which are also known as flying foxes are one of the sources of transmission of NiV disease.Here in this work,we investigate its transmission mechanism through some new concepts of fractional calculus for further analysis and prediction.We present the approximate results for different compartments using different fractional orders.By using the piecewise derivative concept,we detect the crossover ormulti-steps behavior in the transmission dynamics of the mentioned disease.Therefore,the considered form of the derivative is used to deal with problems exhibiting crossover behaviors. 展开更多
关键词 NiV disease fractional calculus piecewise derivative qualitative results newton polynomial RNA virus
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Conformable and Caputo’s Derivatives in Generalized Viscoelastic Models
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作者 Jorge Fujioka Rosalío Fernando Rodríguez Áurea Espinosa-Cerón 《Applied Mathematics》 2023年第9期580-601,共22页
We study two generalized versions of a system of equations which describe the time evolution of the hydrodynamic fluctuations of density and velocity in a linear viscoelastic fluid. In the first of these versions, the... We study two generalized versions of a system of equations which describe the time evolution of the hydrodynamic fluctuations of density and velocity in a linear viscoelastic fluid. In the first of these versions, the time derivatives are replaced by conformable derivatives, and in the second version left-handed Caputo’s derivatives are used. We show that the solutions obtained with these two types of derivatives exhibit significant similarities, which is an interesting (and somewhat surprising) result, taking into account that the conformable derivatives are local operators, while Caputo’s derivatives are nonlocal operators. We also show that the solutions of the generalized systems are similar to the solutions of the original system, if the order α of the new derivatives (conformable or Caputo) is less than one. On the other hand, when α is greater than one, the solutions of the generalized systems are qualitatively different from the solutions of the original system. 展开更多
关键词 Conformable derivatives Caputo’s derivatives Fractional derivatives Viscoelastic Fluids Hydrodynamic Fluctuations
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Modeling Drug Concentration in Blood through Caputo-Fabrizio and Caputo Fractional Derivatives
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作者 Muath Awadalla Kinda Abuasbeh +1 位作者 Yves Yannick Yameni Noupoue Mohammed S.Abdo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2767-2785,共19页
This study focuses on the dynamics of drug concentration in the blood.In general,the concentration level of a drug in the blood is evaluated by themean of an ordinary and first-order differential equation.More precise... This study focuses on the dynamics of drug concentration in the blood.In general,the concentration level of a drug in the blood is evaluated by themean of an ordinary and first-order differential equation.More precisely,it is solved through an initial value problem.We proposed a newmodeling technique for studying drug concentration in blood dynamics.This technique is based on two fractional derivatives,namely,Caputo and Caputo-Fabrizio derivatives.We first provided comprehensive and detailed proof of the existence of at least one solution to the problem;we later proved the uniqueness of the existing solution.The proof was written using the Caputo-Fabrizio fractional derivative and some fixed-point techniques.Stability via theUlam-Hyers(UH)technique was also investigated.The application of the proposedmodel on two real data sets revealed that the Caputo derivative wasmore suitable in this study.Indeed,for the first data set,the model based on the Caputo derivative yielded a Mean Squared Error(MSE)of 0.03095 with a corresponding best value of fractional order of derivative of 1.00360.Caputo-Fabrizio-basedderivative appeared to be the second-best method for the problem,with an MSE of 0.04324 for a corresponding best fractional derivative order of 0.43532.For the second experiment,Caputo derivative-based model still performed the best as it yielded an MSE of 0.04066,whereas the classical and the Caputo-Fabrizio methods were tied with the same MSE of 0.07299.Another interesting finding was that the MSE yielded by the Caputo-Fabrizio fractional derivative coincided with the MSE obtained from the classical approach. 展开更多
关键词 PHARMACOKINETICS caputo fractional derivative stability study Caputo-Fabrizio fractional derivative
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Metal derivative(MD)/g-C_(3)N_(4) association in hydrogen production:A study on the fascinating chemistry behind,current trend and future direction
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作者 Athira Krishnan Muhsina Yoosuf +2 位作者 K.Archana A.S.Arsha Amritha Viswam 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期562-583,I0013,共23页
Metal derivative/graphitic carbon nitride(g-C_(3)N_(4))association is found promising in providing sustainable hydrogen production by photocatalytic water splitting process.Number of works reported on the synthesis an... Metal derivative/graphitic carbon nitride(g-C_(3)N_(4))association is found promising in providing sustainable hydrogen production by photocatalytic water splitting process.Number of works reported on the synthesis and application of various metal based g-C_(3)N_(4)composites are increasing day by day.Mechanism of charge separation varies according to the metal candidate that gets couple with g-C_(3)N_(4).The present article thus explores the interesting chemistry behind various metal based heterojunction and demonstrates the charge separation route.A thorough investigation has been done on the current research trend in the area.As many metal free g-C_(3)N_(4)composites are reported nowadays as an alternative to metal derivatives,here compares metallic and metal free derivatives of g-C_(3)N_(4)based on four critical requirements of an industrial catalyst,ie,activity,stability,cost and toxicity.Challenges and future direction in the area are also discussed with significance.The systematic discussion and schematic illustration of charge transfer process in different heterojunctions with reference to the reported systems,given in the article can definitely contribute to the design and development of more efficient g-C_(3)N_(4)based heterojunctions in future for hydrogen production application. 展开更多
关键词 g-C_(3)N_(4) PHOTOCATALYSIS Hydrogen evolution reaction Water splitting Metal derivatives Non-metal derivatives
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Preparation of Amide-Containing Insecticidal Derivatives from the Renewable Natural Productβ-Pinene
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作者 Jiulong Wang Yanqing Gao +5 位作者 Xiaoping Rao Zongde Wang Shibin Shang Zhanqian Song Hongyan Si Shengliang Liao 《Journal of Renewable Materials》 SCIE EI 2023年第5期2368-2380,共13页
The preparation of bioactive derivatives from the renewable natural product pinene is a hot research topic in the deep processing and utilization of pinene.In this study,β-pinene was used to develop novel molecules a... The preparation of bioactive derivatives from the renewable natural product pinene is a hot research topic in the deep processing and utilization of pinene.In this study,β-pinene was used to develop novel molecules as a promising new precursor of insecticide.A series of amide-containing derivatives ofβ-pinene were synthesized and characterized.The insecticidal activities of these derivatives against Mythimna separate and Semiaphis heraclei were tested.The structure characterization results showed that the characterization data of amide-containing derivatives were in full agreement with their proposed structures.The insecticidal activities evaluation results indicated that amide-containing derivatives exhibited weak insecticidal activity against Mythimna separate,but exhibited moderate to good insecticidal activity against Semiaphis heraclei.After testing for 72 h,the corrected mortality against Semiaphis heraclei of compounds 5c,5e,5f,5 h,5j,and 5 m was 100%at 1000 mg/L.The structure-activity relationship analysis results showed that the introduction of an amide group into the structure of derivatives improved their insecticidal activity against Semiaphis heraclei.Meanwhile,the amide-containing derivatives containing the F and NO_(2) substituted benzene ring might improve their insecticidal activity against Semiaphis heraclei.This study will be helpful for the high value-added utilization of the natural renewable resourceβ-pinene and the development of novel insecticides. 展开更多
关键词 TURPENTINE PINENE derivative AMIDE insecticidal activity
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A Fluorescent Probe based on a Carbazole Derivative for Detecting Brilliant Blue in Food
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作者 YANG Yunqiong YANG Jiaxin +3 位作者 FEI Shaojun ZHANG Zhirui LIU Yang ZHANG Hao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期308-311,共4页
Here a fluorescent probe based on a carbazole derivative(CNS)was developed to increase the detection range and reduce the detection limit of brilliant blue.Characteristics of CNS are studied.Due to the quenching abili... Here a fluorescent probe based on a carbazole derivative(CNS)was developed to increase the detection range and reduce the detection limit of brilliant blue.Characteristics of CNS are studied.Due to the quenching ability of colorants,CNS shows an excellent current response to brilliant blue(from 1 to 10μM)with a detection limit of 2.7×10^(-8)mol/L(3σ/k)in the conditions of a 1:1 volume ratio of water to tetrahydrofuran.And the stability and reproducibility of CNS in the detection of actual samples indicate great potential for application. 展开更多
关键词 fluorescent probe carbazole derivative brilliant blue DETECTION
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Computation of Stiffness and Damping Derivatives of an Ogive in a Limiting Case of Mach Number and Specific Heat Ratio
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作者 Aysha Shabana Asha Crasta +2 位作者 Sher Afghan Khan Abdul Aabid Muneer Baig 《Fluid Dynamics & Materials Processing》 EI 2023年第5期1249-1267,共19页
This work aims to compute stability derivatives in the Newtonian limit in pitch when the Mach number tends to infinity.In such conditions,these stability derivatives depend on the Ogive’s shape and not the Mach numbe... This work aims to compute stability derivatives in the Newtonian limit in pitch when the Mach number tends to infinity.In such conditions,these stability derivatives depend on the Ogive’s shape and not the Mach number.Generally,the Mach number independence principle becomes effective from M=10 and above.The Ogive nose is obtained through a circular arc on the cone surface.Accordingly,the following arc slopes are consideredλ=5,10,15,−5,−10,and−15.It is found that the stability derivatives decrease due to the growth inλfrom 5 to 15 and vice versa.Forλ=5 and 10,the damping derivative declines with an increase inλfrom 5 to 10.Yet,for the damping derivatives,the minimum location remains at a pivot position,h=0.75 for large values ofλ.Hence,whenλ=−15,the damping derivatives are independent of the cone angles for most pivot positions except in the early twenty percent of the leading edge. 展开更多
关键词 Aerodynamic stability derivative Mach number specific heat ratio Ogive
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A Derivative Matrix-Based Covert Communication Method in Blockchain
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作者 Xiang Zhang Xiaona Zhang +3 位作者 Xiaorui Zhang Wei Sun Ruohan Meng Xingming Sun 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期225-239,共15页
The data in the blockchain cannot be tampered with and the users are anonymous,which enables the blockchain to be a natural carrier for covert communication.However,the existing methods of covert communication in bloc... The data in the blockchain cannot be tampered with and the users are anonymous,which enables the blockchain to be a natural carrier for covert communication.However,the existing methods of covert communication in blockchain suffer from the predefined channel structure,the capacity of a single transaction is not high,and the fixed transaction behaviors will lower the concealment of the communication channel.Therefore,this paper proposes a derivation matrix-based covert communication method in blockchain.It uses dual-key to derive two types of blockchain addresses and then constructs an address matrix by dividing addresses into multiple layers to make full use of the redundancy of addresses.Subsequently,to solve the problem of the lack of concealment caused by the fixed transaction behaviors,divide the rectangular matrix into square blocks with overlapping regions and then encrypt different blocks sequentially to make the transaction behaviors of the channel addresses match better with those of the real addresses.Further,the linear congruence algorithm is used to generate random sequence,which provides a random order for blocks encryption,and thus enhances the security of the encryption algorithm.Experimental results show that this method can effectively reduce the abnormal transaction behaviors of addresses while ensuring the channel transmission efficiency. 展开更多
关键词 Covert communication blockchain CONCEALMENT SECURITY capacity derivATION
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Chinese Calligraphy Word Spotting Using Elastic HOG Feature and Derivative Dynamic Time Warping 被引量:1
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作者 Yong Xia Zhi-Bo Yang Kuan-Quan Wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期21-27,共7页
Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document.... Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document. In this paper,we propose a novel Elastic Histogram of Oriented Gradient( EHOG) descriptor for calligraphy word spotting. The presented feature is a modification of Histogram of Oriented Gradient( HOG), widely used in human detection. In our approach,the input word image is partitioned into non-uniform rectangular cells according to the calligraphy character pixel intensity,and then in each cell a histogram of orientation is accumulated dynamically. Moreover,we adopt Derivative Dynamic Time Warping( DDTW) for image feature matching,which achieves good performance in gesture recognition. Experiments demonstrate a very significant improvement when comparing our proposed feature with previously developed ones,and also show DDTW produces superior alignments between two calligraphy character feature series than DTW. 展开更多
关键词 calligraphy word spotting Elastic HOG DDTW
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