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Fungi as chemical industries and genetic engineering for the production of biologically active secondary metabolites

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Asian Pacific Journal of Tropical Biomedicine 2014年第11期4卷 859-870页

作者： Abid Ali Khan Nafees Bacha Bashir Ahmad Ghosia Lutfullah Umar Farooq Russell John Cox department of chemistry.comsats institute of information technology Centre of Biotechnology and Microbiology University of Peshawar department of chemistry.comsats institute of information technology Abbottabad School of chemistry University of Bristol Cantock's Close

Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary *** have been used as tool for producing different types of secondary metabolites by providing different nutrients at different laboratory *** fungi have been engineered for the desired secondary metabolites by using different laboratory techniques,for example,homologous and heterologous *** review reported how the fungi are used as chemical industry for the production of secondary metabolites and how they are engineered in laboratory for the production of desirable metabolites:also the biosynthetic pathways of the bio-organic-molecules were reported.

关键词： Fungi Natural products Microbiology Molecular genetics Chemical biology

Flow-injection Spectrophotometric Determination of Uric Acid in Urine via Prussian Blue Reaction

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Chemical Research in Chinese Universities 2011年第6期27卷 929-933页

作者： WASEEM Amir YAQOOB Mohammad NABI Abdul MURTAZA Ghulam HUSSAIN Izhar department of chemistry COMSATS Institute of Information Technology department of chemistry University of Balochistan department of Pharmacy COMSATS Institute of Information Technology

A simple and sensitive flow injection（FI） spectrophotometric method was reported for the determination of uric acid based on the reduction of Fe（III）/ferricyanide in the presence of uric acid. The in situ reduced ions reacted with unreduced portion of ferricyanide/Fe（III） to form soluble Prussian blue, which was monitored at an absorption wavelength of 735 nm. The optimized conditions allow a linear calibration graph in a concentration range of 1―100 μmol/L. The relative standard deviation was in a range of 0.5%―2.5%, with a detection limit（3σ blank） of 0.3 μmol/L and a sampling frequency of 60 injection/h was obtained. The effect of common substances present in human physiological fluids on the determination of uric acid was examined. The method was applied to determining uric acid in human urine samples with the recoveries in a range of 96%―105%. The results agree well with those by spectrophotometric reference method at a confidence level of 95%. Spectrophotometric procedures for uric acid determination in clinical samples were reviewed briefly.

关键词： Flow injection analysis Spectrophotometry Uric acid Prussian blue Urine

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Bioinspired Ultrasensitive Flexible Strain Sensors for Real‑Time Wireless Detection of Liquid Leakage

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Nano-Micro Letters 2025年第3期17卷 310-327页

作者： Weilong Zhou Yu Du Yingying Chen Congyuan Zhang Xiaowei Ning Heng Xie Ting Wu Jinlian Hu Jinping Qu Key Laboratory of Material chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service Failure and Hubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205People’s Republic of China department of Biomedical Engineering City University of Hong KongHong KongSAR 999077People’s Republic of China

Liquid leakage of pipeline networks not only results in considerableresource wastage but also leads to environmental pollution and ecological *** response to this global issue, a bioinspired superhydrophobic thermoplastic polyurethane/carbon nanotubes/graphene nanosheets flexible strain sensor (TCGS) hasbeen developed using a combination of micro-extrusion compression molding andsurface modification for real-time wireless detection of liquid leakage. The TCGSutilizes the synergistic effects of Archimedean spiral crack arrays and micropores,which are inspired by the remarkable sensory capabilities of scorpions. This designachieves a sensitivity of 218.13 at a strain of 2%, which is an increase of 4300%. Additionally, it demonstrates exceptional durability bywithstanding over 5000 usage cycles. The robust superhydrophobicity of the TCGS significantly enhances sensitivity and stability indetecting small-scale liquid leakage, enabling precise monitoring of liquid leakage across a wide range of sizes, velocities, and compositionswhile issuing prompt alerts. This provides critical early warnings for both industrial pipelines and potential liquid leakage scenariosin everyday life. The development and utilization of bioinspired ultrasensitive flexible strain sensors offer an innovative and effectivesolution for the early wireless detection of liquid leakage.

关键词： Thermoplastic polyurethane Bioinspired Cracks Liquid leakage Flexible strain sensor

Enhancing anion conductivity in a highly alkali-stable eta topologic Cu(Ⅰ) framework via strong electrostatic repulsion

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Science China chemistry 2025年

作者： Xiaolu Wang Shaohui Guo Chao Suo Fuqiang Zhang Junhao Wang Wenjing Wang Daqiang Yuan Linfeng Liang Xianming Zhang College of chemistry Taiyuan University of Technology institute of Crystalline Materials Shanxi University School of chemistry and Materials Science Shanxi Normal University State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Metal-organic frameworks （MOFs） based on anion exchange membranes （AEMs） have garnered considerable interest,particularly for their potential to enhance ion conductivity by pre-introducing anions into *** approach is recognized as straightforward and effective for improving ion ***,developing high-performance AEMs is limited by the inherent instability and low resistance of *** study presents a novel 1,3,5-triazineμ3-bridged neutral Cu（I） framework,designated SXU-120 （where SXU represents Shanxi University）.This framework is synthesized using melamine,a widely available industrial product,as the starting material,achieving a high space-time yield exceeding 1.1 kg *** organic ligands and metal ions in SXU-120 are 3-connected,forming a rare eta topology with the point symbol 8～***-120 exhibits exceptional stability,even in a 10 M KOH solution,due to its high density of uncoordinated–NH2and carbonyl ***,the framework’s unique one-dimensional channels,characterized by their electronegativity,interact electrostatically with OH-ions,thereby accelerating OH-ion transfer along these ***,the OH-conductivity of this material reaches an impressive 0.49 S cm-1at 90°C under full humidity for 100 h,representing the highest OH-conductivity reported for MOF-based conductors to *** properties make SXU-120 a promising candidate for efficient AEM materials in next-generation industrial applications.

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Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China chemistry 2025年

作者： Li-Xu You Lan Tian Chun-Ling Guo Shun-Xi Li Yu-Cheng Liu Yu-Long Li Wei Shu College of chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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Flow-injection Determination of Cysteine,N-Acetyl Cysteine and Glutathione in Pharmaceuticals via Potassium Ferricyanide-Fe(Ⅲ) Spectrophotometric System

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Chemical Research in Chinese Universities 2010年第6期26卷 893-898页

作者： WASEEM Amir YAQOOB Mohammad NABI Abdul department of chemistry COMSATS Institute of Information Technology department of chemistry University of Balochistan

A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe（Ⅲ）/ferricyanide,the in situ reduced ions are reacted with unreduced portion of ferricyanide/Fe（Ⅲ） to form soluble Prussian blue,which is monitored at 735 *** calibration graphs are linear in the concentration ranges of（1―100）×10-6 mol/L for cysteine and N-acetyl cysteine,and（1―50）×10-6 mol/L for *** relative standard deviations of 1.8%,2.5% and 1.9% were found for eleven replicate analyses of 5×10-6 mol/L cysteine,N-acetyl cysteine and *** limits of detection（3σ blank） at 5×10-7 mol/L for cysteine,and 3×10-7 mol/L for N-acetyl cysteine and glutathione were *** proposed method allowed 60 injections/*** effects of common substances present in pharmaceuticals and human physiological fluids were *** method was applied to determining cysteine in pharmaceutical formulations with the recoveries in a range of 97% to 106% and the results obtained are agreed well with labeled values.

关键词： Flow injection Spectrophotometry Cysteine Prussian blue Fe(Ⅲ) Ferricyanide Pharmaceutical

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Buried interface bridging for inverted cesium-formamidinium triiodide perovskite solar cells with long operational stability

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Science China chemistry 2025年第01期 163-173页

作者： Chenhui Zhang Chunjun Liang Fulin Sun Ting Zhu Xinghai Huang Yuzhu Guo Xinyu Guo Kunyang Ge Dan Li Fangtian You Zhiqun He Key Laboratory of Luminescence and Optical information Ministry of Education Institute of Optoelectronic TechnologyBeijing Jiaotong University department of Physics School of Physical Science and Engineering Beijing Jiaotong University

In the field of perovskite solar cells(PSCs), the research on defects in the buried interface has been relatively limited due to its non-exposure; however, this interface significantly impacts the performance enhancement of inverted PSCs. This study employs phenylethylammonium chloride(PEACl) molecules as a buffer layer to modify the buried interface of p-i-n structured PSCs,aiming to enhance the uniformity of self-assembled monolayers(SAMs) and facilitate the uniform nucleation and growth of perovskite films on the substrate. Furthermore, the introduction of the PEACl buffer layer effectively passivates defects at the bottom of the perovskite layer and notably enhances the crystal quality of the perovskite film by mitigating residual stress,thereby reducing nonradiative recombination loss. Following these optimizations, the MA-free PSCs treated with PEACl achieve a power conversion efficiency(PCE) of 24.11%, with significant improvements in storage, thermal stability, and operational stability. Particularly noteworthy is the device's performance in an unencapsulated state, whereas after 1,500 hours of continuous light operation stability testing, it retains 97% of its original efficiency. This study not only enriches the systematic understanding of the characteristics of the buried interface in PSCs but also contributes significantly to advancing the commercial production of perovskite photovoltaic technology.

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Three-Stage Transfer Learning with AlexNet50 for MRI Image Multi-Class Classification with Optimal Learning Rate

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 155-183页

作者： Suganya Athisayamani A.Robert Singh Gyanendra Prasad Joshi Woong Cho School of Computing Sastra Deemed to be UniversityThanjavur613401India department of Computational Intelligence SRM Institute of Science and TechnologyKattankulathur603203India department of AI and Software Engineering Kangwon National UniversitySamcheok25913Republic of Korea department of Electronics Information and Communication EngineeringKangwon National UniversitySamcheok25913Republic of Korea

In radiology,magnetic resonance imaging(MRI)is an essential diagnostic tool that provides detailed images of a patient’s anatomical and physiological *** is particularly effective for detecting soft tissue ***,radiologists manually interpret these images,which can be labor-intensive and time-consuming due to the vast amount of *** address this challenge,machine learning,and deep learning approaches can be utilized to improve the accuracy and efficiency of anomaly detection in MRI *** manuscript presents the use of the Deep AlexNet50 model for MRI classification with discriminative learning *** are three stages for learning;in the first stage,the whole dataset is used to learn the *** the second stage,some layers of AlexNet50 are frozen with an augmented dataset,and in the third stage,AlexNet50 with an augmented dataset with the augmented *** method used three publicly available MRI classification datasets:Harvard whole brain atlas(HWBA-dataset),the School of Biomedical Engineering of Southern Medical University(SMU-dataset),and The National institute of Neuroscience and Hospitals brain MRI dataset(NINS-dataset)for *** hyperparameter optimizers like Adam,stochastic gradient descent(SGD),Root mean square propagation(RMS prop),Adamax,and AdamW have been used to compare the performance of the learning ***-dataset registers maximum classification *** evaluated the performance of the proposed classification model using several quantitative metrics,achieving an average accuracy of 98%.

关键词： MRI tumors classification AlexNet50 transfer learning hyperparameter tuning optimizer

Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China chemistry 2025年第1期 152-156页

作者： Lihua Zhang Lingjing Chen Huatian Shi Yue Wei Gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology department of chemistry and institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

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