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Production of biodiesel from palm fatty acid distillate using sulfonated-glucose solid acid catalyst:Characterization and optimization

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Chinese Journal of Chemical Engineering 2015年第11期23卷 1857-1864页

作者： Ibrahim M.Lokman Umer Rashid yun hin taufiq-yap Catalysis Science and Technology Research Centre Faculty of ScienceUniversiti Putra Malaysia Department of Chemistry Faculty of ScienceUniversiti Putra Malaysia School of Chemistry Faculty of Applied SciencesUniversiti Teknologi MARA Institute of Advanced Technology Universiti Putra Malaysia

A palm fatty acid distillate （PFAD） has been used for biodiesel production. An efficient sulfonated-glucose acid catalyst （SGAC） was prepared by sulfonation to catalyze the esterification reaction. The effect of three variables i.e. methanol-to-PFAD molar ratio, catalyst amount and reaction time, on the yield of PFAD esters was studied by the response surface methodology （RSM）. The optimum reaction conditions were： 12.2：1 methanol-to- PFAD molar ratio, 2.9% catalyst concentration and 134 rain of time as predicted by the RSM. The reaction under the optimum conditions resulted in 94.5% of the free fatty acid （FFA） conversion with 92.4% of the FAME yield. The properties of the PFAD esters were determined according to biodiesel standards.

关键词： Palm fatty acid distillate (PFAD)5ulfonated-glucose solid acid catalystEsterificationOptimizationPFAD methyl ester

铋和镍对钒磷氧化物催化剂性能的影响(英文)

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催化学报 2014年第2期35卷 270-276页

作者： yun hin taufiq-yap Choon Seon Yuen Nawi Mohamed Nurul Suziana Ramli Irmawati Catalysis Science and Technology Research Centre Faculty of ScienceUniversity Putra Malaysia Department of Chemistry Faculty of ScienceUniversiti Putra Malaysia

Vanadium phosphorus oxide (VPO) catalysts were synthesized by the dihydrate method which involved the two steps for the preparation of the dihydrate (VOPO4 2H2 O) and the precursor hemi-hydrate (VOHPO4 0.5H2 O). Bi and Ni salt were added into the mixture of VOPO4 2H2 O and isobu-tanol, and the obtained precursors were calcined in a flow of a n-butane/air mixture to produce the promoted VPO catalysts. The catalysts were characterized by X-ray diffraction (XRD), N2 adsorp-tion- desorption, inductively coupled plasma-atomic emission spectroscopy, scanning electron mi-croscopy (SEM), and H2 temperature-programmed reduction (H2 -TPR). Their catalytic properties were tested using a fixed-bed microreactor. All the catalysts gave main XRD peaks at 2θ = 22.9°, 28.5°, and 30.0°, attributing to the (020), (204), and (221) planes of the pyrophosphate phase (VO)2 P2 O7, respectively. The promoted catalysts have smaller crystallite size and higher specific surface areas. SEM micrographs revealed the formation of more prominent plate-like crystallites that were arranged as rosette clusters. H2 -TPR results showed that the promoted catalysts had lower reduction peak temperatures and possessed higher amounts of V5+-O2– and V4+-O– pairs, which gave higher selectivity and activity in the selective oxidation of n-butane to maleic anhydride.

关键词：氧化物催化剂钒磷氧化物催化性能电感耦合等离子体原子发射光谱法 Bi 镍盐 VPO催化剂扫描电子显微镜

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掺Ni钒磷氧化物催化剂的合成和表征

催化学报 2007年第12期28卷 1037-1040页

作者： taufiq-yap yun hin ABDUL GHANI Abdul Aziz 博特拉大学科学院化学系博特拉科学和技术实验室

以VOPO4.2H2O为原料制备了钒磷氧化物催化剂,考察了镍掺杂(1%,2%和5%)对该催化剂的影响.低掺杂量的Ni明显提高了活性晶格氧物种O-的数量,降低了V5+和V4+相的还原峰温.粉末X射线衍射、程序升温还原和化学分析结果表明,高掺杂量的Ni促使V5... 详细信息

以VOPO4.2H2O为原料制备了钒磷氧化物催化剂,考察了镍掺杂(1%,2%和5%)对该催化剂的影响.低掺杂量的Ni明显提高了活性晶格氧物种O-的数量,降低了V5+和V4+相的还原峰温.粉末X射线衍射、程序升温还原和化学分析结果表明,高掺杂量的Ni促使V5+物相生成并抑制V4+物相出现.高含量与V5+相关的氧物种会降低正丁烷的转化率,但会提高马来酸酐的选择性.

关键词：焦磷酸钒酰镍正丁烷氧化马来酸酐

Synthesis, Characterization and Phytotoxicity Assessment of Intercalated Insect Pheromone, Lignoceric Acid-Zinc Layered Hydroxide Nanohybrid

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Journal of Environmental Science and Engineering(B) 2023年第2期12卷 75-91页

作者： Rozita Ahmad Mohd Zobir Hussein Siti Halimah Sarijo Wan Rasidah Wan Abdul Kadir taufiq-yap yun hin Forest Biotechnology Division Forest Research Institute MalaysiaKepong 52109SelangorMalaysia Institute of Nanoscience and Nanotechnology Universiti Putra MalaysiaSerdang 43400SelangorMalaysia Faculty of Applied Science Universiti Teknologi MARAShah Alam 40540SelangorMalaysia Chemistry Department Faculty of ScienceUniversiti Putra MalaysiaSerdang 43400SelangorMalaysia

A long chain insect pheromone for subterranean termites, LC (Lignoceric Acid), was intercalated into the inorganic interlayer, ZLH (Zinc Layered Hydroxide), resulting in the formation of a new nanohybrid, labelled as LCN (Lignocerate Nanohybrid). The formation of this inorganic-organic structure nanohybrid was synthesized by the co-precipitation method using ZnO (Zinc Oxide) as the starting material. The PXRD (Powder X-Ray Diffraction) results confirmed the intercalation process although the diffraction patterns of the resultant nanohybrid and the unbound pheromone were fairly similar but both have different basal spacings values. The FTIR (Fourier Transform Infrared) profiles and the chemical composition test supported the intercalation process with the percentage loading of LC into ZLH calculated to be 85%. The thermal stability of the free anion, LC was enhanced when it was transformed into LCN, increasing from 257 °C to 352 °C. The release of LC from the nanohybrid behaved in a sustained manner, governed by the pseudo-second order kinetic model with higher release of LC in sodium carbonate solution than the pH aqueous media. The synthesized nanohybrid was found to be safe for plant germination when the two seed types were successfully germinated in all the tested nanohybrid concentrations. However, the percentage seed germination and the radical seed length from the nanohybrid showed lower values compared to its counterpart anion, LC.

关键词： Insect pheromone ZLH ZnO controlled release termite

Image-Based Automatic Diagnostic System for Tomato Plants Using Deep Learning

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Computers, Materials & Continua 2021年第4期67卷 595-612页

作者： Shaheen Khatoon Md Maruf Hasan Amna Asif Majed Alshmari yun-Kiam yap College of Computer Science and Information Technology King Faisal UniversityAl-Ahsa31982Saudi Arabia College of Science King Faisal UniversityAl-Ahsa31982Saudi Arabia

Tomato production is affected by various threats,including pests,pathogens,and nutritional deciencies during its growth *** control is not timely,these threats affect the plant-growth,fruit-yield,or even loss of the entire crop,which is a key danger to farmers’livelihood and food *** plant disease diagnosis methods heavily rely on plant pathologists that incur high processing time and huge *** and cost-effective methods are essential for timely detection and early intervention of basic food threats to ensure food security and reduce substantial economic *** developments in Articial Intelligence(AI)and computer vision allow researchers to develop image-based automatic diagnostic tools to quickly and accurately detect *** this work,we proposed an AI-based approach to detect diseases in tomato *** goal is to develop an end-to-end system to diagnose essential crop problems in real-time,ensuring high *** paper employs various deep learning models to recognize and predict different diseases caused by pathogens,pests,and nutritional *** Convolutional Neural Networks(CNNs)are trained on a large dataset of leaves and fruits images of tomato *** compared the performance of ShallowNet(a shallow network trained from scratch)and the state-of-theart deep learning network(models are ne-tuned via transfer learning).In our experiments,DenseNet consistently achieved high performance with an accuracy score of 95.31%on the test *** results verify that deep learning models with the least number of parameters,reasonable complexity,and appropriate depth achieve the best *** experiments are implemented in Python,utilizing the Keras deep learning library backend with TensorFlow.

关键词： Tomato plant disease classication and prediction deep learning convolutional neural network RestNet VGGNet DenseNet

Rectal arterio-portal fistula: An unusual cause of persistent bleeding per rectum following a proximal spleno-renal shunt

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World Journal of Gastroenterology 2013年第25期19卷 4087-4090页

作者： Hao yun yap Ser Yee Lee Yaw Fui Alexander Chung Kiang Hiong Tay Albert Su-Chong Low Choon Hua Thng Krishnakumar Madhavan Department of General Surgery Singapore General Hospital Department of Surgical Oncology National Cancer Centre Singapore Department of Diagnostic Radiology Singapore General Hospital Department of Oncologic Imaging National Cancer Centre Singapore Department of General Surgery National University Hospital Singapore

Gastrointestinal arterio-venous malformations are a known cause of gastrointestinal bleeding. We present a rare case of persistent rectal bleeding due to a rectal arterio-portal venous fistula in the setting of portal hypertension secondary to portal vein thrombosis. The portal hypertension was initially surgically treated with splenectomy and a proximal splenorenal shunt. However, rectal bleeding persisted even after surgery, presenting us with a diagnostic dilemma. The patient was re-evaluated with a computed tomography mesenteric angiogram which revealed a rectal arterio-portal fistula. Arterio-portal fistulas are a known but rare cause of portal hypertension, and possibly the underlying cause of continued rectal bleeding in this case. This was successfully treated using angiographic localizationand super-selective embolization of the rectal arterioportal venous fistula via the right internal iliac artery. The patient subsequently went on to have a full term pregnancy. Through this case report, we hope to high-light awareness of this unusual condition, discuss the diagnostic workup and our management approach.

关键词： Portal hypertension Esophageal varices Splenorenal shunt Arteriovenous malformations Portal vein thrombosis

Efficient transcription of the larvicidal cry4Bagene from Bacillus thuringiensisin transgenic chloroplasts of the green algal Chlamydomonas reinhardtii

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Advances in Bioscience and Biotechnology 2012年第4期3卷 362-369页

作者： Thanate Juntadech Kittisak Yokthongwattana Sithichoke Tangphatsornruang yun-kiam yap Gerd Katzenmeier Chanan Angsuthanasombat Department of Biochemistry and Center for Excellence in Protein Structure and Function Faculty of Science Mahidol University Bangkok Thailand DivisionInstitute of Molecular Biosciences Mahidol University Salaya Campus Nakornpathom Thailand National Center for Genetic Engineering and Biotechnology Thailand Science Park Pathumthani Thailand

Unicellular micro-alga Chlamydomonas reinhardtii has been recognized as a promising host for expressing recombinant proteins albeit its limited utility due to low levels of heterologous protein expression. Here, transcription of the 3.4-kb mosquito-larvicidal cry4Ba gene from Bacillus thuringiensis in transgenic C. reinhardtii chloroplasts under control of the promoter and 5’-untranslated region of photosynthetic psbA gene was accomplished. Inverted repeats in chloroplast genomes of the host strain with deleted endogenous psbA genes were selected as recombination targets. Two transformant lines were obtained by dual-phenotypic screening via exhibition of resistance to spectinomycin and restoration of photosynthetic activity. Stable and site-specific integration of intact cry4Ba and psbA genes into chloroplast genomes found in both transgenic lines implied homoplasmy of organelle populations. Achievement in cotranscription of cry4Ba and psbA transgenes revealed by RT-PCR and Northern blot analyses demonstrates the sufficiency of this system’s transcription machinery, offering the further innovation for insecticidal protein production.

关键词： Chlamydomonas reinhardtii Chloroplast Transformation Inverted Repeats Bt-cry4Ba Transcript psbA Promoter

Mechanisms of ductular reaction in non-alcoholic steatohepatitis

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World Journal of Gastroenterology 2022年第19期28卷 2088-2099页

作者： Yue Chen Wen-Kang Gao Yan-yun Shu Jin Ye Division of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

Non-alcoholic fatty liver disease(NAFLD)is a disease spectrum caused in part by insulin resistance and genetic *** disease is primarily characterized by excessive lipid accumulation in hepatocytes in the absence of alcohol abuse and other causes of liver ***,NAFLD is divided into several periods:simple steatosis,non-alcoholic steatohepatitis(NASH),hepatic fibrosis,cirrhosis,and hepatocellular *** the increasing prevalence of obesity and hyperlipidemia,NAFLD has become the main cause of chronic liver disease *** a result,the pathogenesis of this disease is drawing increasing *** reaction(DR)is a reactive bile duct hyperplasia caused by liver injury that involves hepatocytes,cholangiocytes,and hepatic progenitor ***,DR is shown to play a pivotal role in simple steatosis progression to NASH or liver fibrosis,providing new research and treatment *** study reviews several DR signaling pathways,including Notch,Hippo/yap-TAZ,Wnt/β-catenin,Hedgehog,HGF/c-Met,and TWEAK/Fn14,and their role in the occurrence and development of NASH.

关键词： Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis Ductular reaction Mechanisms Signaling pathways

Relief of yap-mediated inhibition by IKKε promotes innate antiviral immunity

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Cellular & Molecular Immunology 2018年第6期15卷 642-644页

作者： Nayoung Kim yun-Yong Park Chul Hyun Joo Hun Sik Kim Department of Convergence Medicine Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505Korea Asan Institute for Life Sciences Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505Korea Department of Microbiology Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505Korea Department of Biomedical Sciences Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505Korea

The innate immune response to invading viruses is critical for the mounting of protective immunity,in which type I interferons(IFN),for example,IFN-αandβ,are potent effector molecules.1 Most cell types,particularly fibroblasts and epithelial cells,produce IFN-β,whereas hematopoietic cells,notably plasmacytoid dendritic cells,are the predominant sources of IFN-α.IFNs potently stimulate a variety of innate and adaptive immune cells,including macrophages,NK cells and T *** binding of type I IFN to its cognate receptor triggers the activation of the Janus kinase signal transducer and activator of transcription pathway,which results in the transcription of IFNstimulated genes that play key roles in host resistance to viral infections.

关键词： immunity protective mount