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Optimization of ionic liquid-based microwave-assisted extraction of polyphenolic content from Peperomia pellucida (L) kunth using response surface methodology

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Asian Pacific Journal of Tropical Biomedicine 2017年第7期7卷 660-665页

作者： Islamudin ahmad Arry Yanuar Kamarza Mulia abdul Mun'im Department of Pharmaceutical Sciences Faculty of Pharmacy Mulawarman University Samarinda East Kalimantan Indonesia Department of Pharmaceutical Sciences Faculty of Pharmacy Universitas Indonesia Depok 16424 West Java Indonesia Department of Chemical Engineering Faculty of Engineering Universitas Indonesia Depok 16424 West Java Indonesia

Objective: To optimize the ionic liquid based microwave-assisted extraction(IL-MAE)of polyphenolic content from Peperomia pellucida(L) ***: The IL-MAE factors as experimental design parameters, including microwave power, extraction time, ionic liquid concentration, and liquid–solid ratio had been involved. Response surface methodology and Box–Behnken design were used to obtain predictive model(multivariate quadratic regression equation) and optimization of the extraction process. The response surface was analyzed by using the yields of total polyphenolic content as response ***: Based on the obtained results the optimum extraction condition, including microwave power of 30% Watts, extraction time of 18.5 min, the ionic liquid concentration of 0.79 mol/L, and the liquid–solid ratio of 10.72 mL/g 1-Buthyl-3-methylimidazolium tetrafluoroborate([bmim]BF_4) as a solvent was selected. The regression model was obtained to predicts the yields from Peperomia pellucida:Y = 30.250 – 1.356X_1+ 2.655X_2+ 2.252X_3– 0.565X_4+ 0.990 X_1X_3– 8.172X_1X_4– 3.439 X_3X_4– 4.178 X_1~2– 3.210 X_3~2– 6.786 X_4~2– 7.290 X_1~2X_3+ 5.575X1_X_3~2– 4.843 X_3~2X_4 with R^2= 0.82519. Scale-up confirmation test was obtained the maximum yields of total polyphenolics content with the amount of 31.172 5 mg GAE/***: The IL-MAE method produced a higher extraction polyphenolic and performed rapidly, easily and efficiently.

关键词： Peperomia pellucida (L) Kunth 1-buthyl-3-methylimidazolium Tetrafluoroborate 反应表面方法论 Box-Behnken 设计 Polyphenolic 内容

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Biochemical studies on malathion resistance, inheritance and association of carboxylesterase activity in brown planthopper, Nilaparvata lugens complex in Peninsular Malaysia

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Insect Science 2010年第6期17卷 517-526页

作者： M. A. latif Mohd Yosuh Omar Soon Guan Tan S.S. Siraj abdul Rahim Ismail Department of Crop Science Faculty of Agriculture Department of Biology Faculty of Science Department of Cell and Molecular Biology Faculty of Biotechnology and Molecular Science Department of Aquaculture Faculty of Agriculture Universiti Putra Malaysia Serdang Selangor Malaysia

Two sympatric populations of brown planthopper （BPH）, one from rice and the other from Leersia hexandra were collected from each of five locations in Malaysia. All the tested malathion-resistant individuals of the rice BPH population and F1 generation （cross between malathion-resistant [usually caught on rice] and malathion- susceptible [usually caught on Leersia]） showed high esterase activity, while all malathion- susceptible individuals on L. hexandra showed low esterase activity. In the F2 generation, all the individuals tested against malathion were approximately 75% resistant and 25% susceptible and the inheritance pattern of esterase activity （high and low esterase activity） segregated in the same manner to a 3：1 ratio. This confirms that resistance to malathion is mono-factorial and inheritance pattern ofesterase activity is also linked to malathion resistance. Carboxylesterase or total esterase activity in BPH is inherited in a simple Mendelian fashion that is encoded by a single dominant gene. For the total esterase assay, average esterase activity levels in the rice-infesting population ranged from 17.64 to 19.37 nmoles 1-napthol/mg protein while that in the Leersia-infesting population ranged from 5.29 to 6.11 nmoles 1-napthol/mg protein. In terms of esterase activity, the two sympatric Nilaparvata lugens populations separated into two distinct groups. Results based on the tube color intensity test showed 96% and 98% resistant and susceptible individuals were present in the rice- and Leersia-infesting populations, respectively. In a filter paper test, the rice-infesting population had 94% with high esterase activity while the Leersia-infesting population had 96% with low esterase activity.

关键词： brown planthopper carboxylesterase assay inheritance study insecticide resistance rice

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An unusual bioactive oleanane triterpenoid from Rhododendron campanulatum ***

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Chinese Chemical Letters 2011年第5期22卷 575-579页

作者： Mudasir ahmad Tantry Reehana Khan Seema Akbar abdul Rouf Dar abdul Sami Shawl Mohammad Sarwar Alam Drug Standardisation Research Unit Regional Research Institute of Unani Medicine(CCRUM)Naseem Bagh CampusUniversity of KashmirSrinagar 190006KashmirIndia Natural Product Chemistry Division Indian Institute of Integrative Medicine(CSIR)SanatnagarSrinagar 190005KashmirIndia Department of Chemistry Jamia Hamdard UniversityHamdard NagarNew Delhi 110062India Bioorganic Chemistry Division Indian Institute of Integrative Medicine(CSIR)Canal RoadJammu Tawi 180001JammuIndia

An unusual oleanane triterpene（1） was isolated from aerial parts of Rhododendron *** compound had shown prominent antibacterial and immunomodulatory *** structure of the compound was determined by spectroscopic data... 详细信息

关键词： Rhododendron campanulatum Oleanane triterpenoid Antibacterial Immunomodulatory

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Synthesis of titanium oxycarbonitride by carbothermal reduction and nitridation of ilmenite with recycling of polyethylene terephthalate (PET)

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International Journal of Minerals,Metallurgy and Materials 2017年第4期24卷 444-454页

作者： Eltefat ahmadi ahmad Fauzi Hashim Hussin Norlia Baharun Kamar Shah Ariffin Sheikh abdul Rezan School of Materials & Mineral Resources Engineering Universiti Sains Malaysia Engineering Campus 14300 Nibong Tebal Penang Malaysia

An innovative and sustainable carbothermal reduction and nitridation(CTRN) process of ilmenite(FeTiO_3) using a mixture of polyethylene terephthalate(PET) and coal as the primary reductant under an H_2–N_2 atmosphere was proposed. The use of PET as an alternative source of carbon not only enhances the porosity of the pellets but also results in the separation of Fe from titanium oxycarbonitride(TiOxCyNz) particles because of the differences in surface tension. The experiments were carried out at 1250°C for 3 h using four different PET contents ranging from 25wt% to 100wt% in the reductant. X-ray diffraction(XRD),scanning electron microscopy(SEM) in conjunction with energy-dispersive X-ray spectroscopy(EDX),and LECO elemental analysis were used to study the phases and microstructures of the reduced samples. In the case of 75wt% PET,iron distinctly separated from the synthesized Ti OxCyNz phase. With increasing PET content in the sample,the reduction and nitridation rates substantially increased. The synthesis of an oxycarbonitride with stoichiometry of TiO_(0.02)C_(0.13)N_(0.85) with minimal intermediate titanium sub-oxides was achieved. The results also showed that the iron particles formed from CTRN of FeTiO_3 exhibited a spherical morphology,which is conducive for Fe removal via the Becher process.

关键词： carbothermal reduction nitridation polyethylene terephthalate titanium oxycarbonitride ilmenite

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Brain Tumor Classification Based on Fine-Tuned Models and the Ensemble Method

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Computers, Materials & Continua 2021年第6期67卷 3967-3982页

作者： Neelum Noreen Sellapan Palaniappan abdul Qayyum Iftikhar ahmad Madini O.Alassafi Department of Information Technology Malaysia University of Science and TechnologySelangor47810Malaysia Department of Information and Engineering Le2i Laboratory University of Burgundy Dijon21078France Department of Information Technology Faculty of Computing and Information Technology King abdulaziz University Jeddah21589Saudi Arabia

Brain tumors are life-threatening for adults and ***,accurate and timely detection can save *** study focuses on three different types of brain tumors:Glioma,meningioma,and pituitary *** studies describe the analysis and classification of brain tumors,but few have looked at the problem of feature *** are needed to overcome the drawbacks of manual diagnosis and conventional featureengineering *** automatic diagnostic system is thus necessary to extract features and classify brain tumors *** progress continues to be made,the automatic diagnoses of brain tumors still face challenges of low accuracy and high false-positive *** model presented in this study,which offers improvements for feature extraction and classification,uses deep learning and machine learning for the assessment of brain *** learning is used for feature extraction and encompasses the application of different models such as fine-tuned Inception-v3 and fine-tuned *** classification of brain tumors is explored through deep-and machine-learning algorithms including softmax,Random Forest,Support Vector Machine,K-Nearest Neighbors,and the ensemble *** results of these approaches are compared with existing *** Inception-v3 model has a test accuracy of 94.34%and achieves the highest performance compared with other recently reported *** improvement may be sufficient to support a significant role in clinical applications for brain tumor ***,this type of approach can be used as an effective decisionsupport tool for radiologists in medical diagnostics as a second opinion based on the magnetic resonance imaging(MRI)*** may also save valuable time for radiologists who have to manually review numerous MRI images of patients.

关键词： Inception Xception classification deep learning feature extraction MRI

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Neuro-heuristic computational intelligence for solving nonlinear pantograph systems

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Frontiers of Information Technology & Electronic Engineering 2017年第4期18卷 464-484页

作者： Muhammad Asif Zahoor RAJA Iftikhar ahmad Imtiaz KHAN Muhammed Ibrahem SYAM abdul Majid WAZWAZ Department of Electrical Engineering COMSA Ts Institute of Information Technology Attock 43200 Pakistan Department of Mathematics University of Gujrat Gujrat 50700 Pakistan Department of Mathematics Preston University lslamabad Campus Kohat Islamabad 44000 Pakistan Department of Mathematical Scienees United Arab Emirates University Al-Ain Box 15551 UAE Department of Mathematics Saint Xavier University Chicago IL 60655 USA

本文提出了一种启发式神经网络计算平台,用于解决基于不同阶数泛函微分方程的非线性受电弓系统(Pantograph systems based on functional differential equations,P-FDEs)中的初值问题(Initial value problems,IVPs)。该方案利用了前馈人工神经网络(Artificial neural networks,ANNs)、基于遗传算法(Genetic algorithms,GAs)的进化计算技术,以及内点技术(Interior-point technique,IPT)。通过设定一个无监督学习误差,针对完全和不完全满足初始条件两种情况,利用ANNs创建了系统的两种数学模型。采用GA–IPT混合算法,对ANN模型的设计参数进行了优化。在GA–IPT中,GA是有效的全局搜索工具,IPT则用于快速的局部收敛。针对三种不同类型的1–3阶P-FDEs的IVPs对该方案进行了测试。通过对比现有的精确解,确认了该方案的正确性。通过采用不同数量神经元的ANN模型进行了大量的数值实验,进一步验证了该方案的准确性和收敛性。

关键词：神经网络初值问题(IVP) 函微分方程(FDE) 无监督学习遗传算法(GAs) 内点技术(IPT)

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A low complexity online controller using fuzzy logic in energy harvesting WSNs

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Science China(Information Sciences) 2019年第4期62卷 167-176页

作者： Talha AZFAR Waqas AHMED abdul HASEEB Rizwan ahmad Sufi Tabassum GUL Fu-Chun ZHENG Department of Electrical Engineering Pakistan Institute of Engineering and Applied Sciences (PIEAS) School of Electrical Engineering and Computer Science National University of Sciences and Technology (NUST) School of Electronic and Information Engineering Harbin Institute of Technology

In this paper, we present a fuzzy logic based scheme for a two hop energy harvesting(EH)wireless sensor network(WSN). Incorporating data and energy causality constraints, discrete transmission rates, finite energy and data buffers, a fuzzy model is developed which uses network throughput, battery level and channel gain as inputs. The fuzzy scheme is then compared with optimum, modified optimum, and Markov decision process(MDP) schemes in terms of computational complexity, throughput, battery level and data buffer capacity. The throughput results show that the fuzzy online scheme preforms closely to the compared schemes and avoids battery depletion even when the number of discrete transmission rates are increased.

关键词： wireless sensor networks energy harvesting cooperative communications fuzzy logic

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Simulation of snowmelt-runoff under climate change scenarios in a data-scarce mountain environment

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International Journal of Digital Earth 2019年第8期12卷 910-930页

作者： Adnan ahmad Tahir Samreen abdul Hakeem Tiesong Hu Huma Hayat Muhammad Yasir Department of Environmental Sciences COMSATS Institute of Information TechnologyAbbottabadPakistan State Key Laboratory of Water Resources and Hydropower Engineering Sciences Wuhan UniversityWuhanPeople’s Republic of China

Pakistan is an agriculture-based economy and major proportion of irrigation water for its cultivated lands is abstracted from the Upper Indus Basin(UIB).UIB water supplies are mostly contributed from the high-altitude snow and glacier fields situated in the Hindukush–Karakoram–Himalayan *** change in the flows of these river catchments due to climate variability may result in the form of catastrophic events like floods and droughts and hence will adversely affect the economy of *** study aims to simulate snowmelt runoff in a mountainous sub-catchment(Shyok River basin)of the UIB under climate change *** Runoff Model(SRM)coupled with remotely sensed snow cover product(MOD10A2)is used to simulate the snowmelt runoff under current and future climate scenarios in the study *** results indicate that(a)SRM has efficiently simulated the flow in Shyok River with average Nash–Sutcliff coefficient value(R2)of 0.8(0.63–0.93)for all six years(2000–2006)of basin-wide and zone-wise simulations,(b)an increase of 10%(by 2050)and 20%(by 2075)in SCA will result in a flow rise of∼11%and∼20%,respectively,and(c)an increase of 1℃(by 2025),2℃(by 2050),3℃(by 2075)and 4℃(by 2100)in mean temperature will result in a flow rise of∼26%,∼54%,∼81%and∼118%,*** study suggests that SRM equipped with remotely sensed snow cover data is an effective tool to estimate snowmelt runoff in high mountain data-scarce environments.

关键词： Upper Indus Basin(UIB) Shyok River basin MOD10A2 Snowmelt Runoff Model(SRM) climate change

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Influence of diversion angle on water and sediment flow into diversion channel

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International Journal of Sediment Research 2020年第6期35卷 600-608页

作者： Nashwan Kamalaldeen Alomari Badronnisa Yusuf Thamer ahmad Mohammad abdul Halim Ghazali Department of Dams and Water Resources College of EngineeringUniversity of Mosul Department of Civil Engineering Faculty of EngineeringUniversiti Putra MalaysiaUPM Serdang Department of Water Resources Engineering University of Baghdad

Accumulation of the sediment in the stream of the diversion channels adversely affects its operational *** channels are often constructed perpendicular to the main *** this study,the water flow and sediment transport in the diversion channel with different angles were investigated in an attempt to maximize water discharge and minimize sediment discharge.A physical model with movable bed was used to simulate water and sediment flow with five diversion angles(θ) between(30°-90°).Moreover,three bed width ratios(Br)(the relation between diversion to main channel bed width) between 30% and 50% and five total discharges between(7.25 L/s to 12.25 L/s) were considered for each case of(θ).The results showed,up to 10%,increasing in proportion discharge ratios for 30 and 45 diversion angles compared with 90° diversion *** results also showed that the lowest diversion sediment concentration was provided by the(0) of *** all scenarios,the average proportion concentration reduction was 64%,compared with 90°diversion *** observation of the diversion system mechanism confirmed that decreased(θ) result in decreased sediment concentrations in the diversion *** conclusion,the diversion channel water and sediment discharge could be effectively managed by changing the(θ) to 30° or 45° instead of 90°.

关键词： Diversion channel Diversion angle Lowest diversion sediment concentration Bed width ratio Sediment concentration

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Standardization of proton-induced x-ray emission technique for analysis of thick samples

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Chinese Physics B 2015年第9期24卷 171-176页

作者： Shad Ali Johar Zeb abdul Ahad Ishfaq ahmad M.Haneef Jehan Akbar Department of Physics Hazara University National Center of Physics (NCP)

This paper describes the standardization of the proton-induced x-ray emission（PIXE） technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials（SRMs） were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 Me V obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.

关键词： standardization thick samples PIXE analysis

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