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A Short Synthesis of Natural Isocoumarin Glucoside Delphoside

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Chinese Journal of Chemistry 2005年第6期23卷 762-766页

作者： saeed,Aamer DepartmentofChemistry Quaid-l-AzamUniversity45320lslamabadPakistan

A simple synthesis of delphoside, 3‐methyl‐6‐hydroxy‐8‐ O ‐β‐ D ‐glucopyranosyloxy isocoumarin ( 1 ), isolated from Delphinium spp. is described. 3,5‐Dimethoxyhomophthalic anhydride ( 2 ) on treatment with acetyl chloride in the presence of 1,1,3,3‐tetramethylguanidine (TMG) and triethyl amine afforded the 6,8‐dimethoxy‐3‐methylisocoumarin ( 3 ). Regioselective demethylation of the latter furnished 8‐hydroxy‐6‐methoxy‐3‐methylisocoumarin ( 4 ). Glycosylation with O ‐(2,3,4,6‐tetra‐ O ‐acetyl‐ D ‐glucopyranosyl)trichloroacetimidate in presence of catalytic amount of boron trifluoride etherate followed by deacetylation using 5% potassium carbonate afforded 3‐methyl‐6‐methoxy‐8‐ O ‐β‐ D ‐glucopyranosyloxyisocoumarin ( 6 ) that was finally demethylated to yield delphoside 1 .

关键词： isocoumarin glucoside glycosylation total synthesis delphoside

Efficiency of employing fiber-based finite-length plastic hinges in simulating the cyclic and seismic behavior of steel hollow columns compared with other common modelling approaches

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 777-794页

作者： Mojtaba Farahi saeed Erfani Department of Civil Engineering Amirkabir University of Technology

The accuracy and effi ciency of the modelling techniques utilized to model the nonlinear behavior of structural components is a signifi cant issue in earthquake engineering. In this study, the suffi ciency of three diff erent modelling techniques that can be employed to simulate the structural behavior of columns is investigated. A fi ber-based fi nite length plastic hinge (FB-FLPH) model is calibrated in this study. In order to calibrate the FB-FLPH model, a novel database of the cyclic behavior of hollow steel columns under simultaneous axial and lateral loading cycles with varying amplitudes is used. By employing the FB-FLPH model calibrated in this study, the interaction of the axial force and the bending moment in columns is directly taken into account, and the deterioration in the cyclic behavior of these members is implicitly considered. The superiority of the calibrated FB-FLPH modelling approach is examined compared with the cases in which conventional fi ber-based distributed plasticity and concentrated plasticity models are utilized. The effi ciency of the enumerated modelling techniques is probed when they are implemented to model the columns of a typical special moment frame in order to prove the advantage of the FB-FLPH modelling approach.

关键词： cyclic behavior seismic behavior fi ber-based fi nite-length plastic hinge model fi ber-based modelling techniques cyclic strength deterioration axial force-bending moment interaction

Electrical annealing of severely deformed copper: microstructure and hardness

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1158-1168页

作者： saeed Nobakht Mohsen Kazeminezhad Department of Materials Science and Engineering Sharif University of Technology Azadi Avenue Tehran Iran

Commercial pure copper sheets were severely deformed after primary annealing to a strain magnitude of 2.32 through constrained groove pressing. After induction of an electrical current, the sheets were heated for 0.5, 1, 2, or 3 s up to maximum temperatures of 150, 200, 250, or 300℃. To compare the annealing process in the current-carrying system with that in the current-free system, four other samples were heated to 300℃ at holding times of 60, 90, 120, or 150 s in a salt bath. The microstructural evolution and hardness values of the samples were then investigated. The results generally indicated that induction of an electrical current could accelerate the recrystallization process by decreasing the thermodynamic barriers for nucleation. In other words, the current effect, in addition to the thermal effect, enhanced the diffusion rate and dislocation climb velocity. During the primary stages of recrystallization, the grown nuclei of electrically annealed samples showed greater numbers and a more homogeneous distribution than those of the samples annealed in the salt bath. In the fully recrystallized condition, the grain size of electrically annealed samples was smaller than that of conventionally annealed samples. The hardness values and metallographic images obtained indicate that, unlike the conventional annealing process, which promotes restoration phenomena with increasing heating time, the electrical annealing process does not necessarily promote these phenomena. This difference is hypothesized to stem from conflicts between thermal and athermal effects during recrystallization.

关键词： annealing severe plastic deformation copper microstructure hardness

Oxa-Pictet-Spengler reaction in *** of some(±)-1-aryl-6,7-dimethoxyisochromans

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Chinese Chemical Letters 2010年第3期21卷 261-264页

作者： Aamer saeed Department of Chemistry Quaid-I-Azam University

An acid catalyzed oxa-Pictet-Spengler reaction‘on water leading to the synthesis of a variety of l-aryl-6,7-dimethoxyisochro-mans is *** aqueous chemistry is a much cleaner,efficient,cheaper and simple method for ***... 详细信息

关键词： Oxa-Pictet-Spengler reaction In water 1-Aryl-6 7-dimethoxyisochromans Isothiochromans

Genome-wide association analysis for stripe rust resistance in spring wheat(Triticum aestivum L.) germplasm

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Journal of Integrative Agriculture 2020年第8期19卷 2035-2043页

作者： Sher MUHAMMAD Muhammad SAJJAD Sultan Habibullah KHAN Muhammad SHAHID Muhammad ZUBAIR Faisal saeed AWAN Azeem iqbal KHAN Muhammad Salman MUBARAK Ayesha TAHIR Muhammad UMER Rumana KEYANI Muhammad InamAFZAL Irfan MANZOOR Javed iqbal WATTOO Aziz-ur REHMAN Department of Bioinformatics and Biotechnology GC UniversityFaisalabad 38090Pakistan Department of Biosciences COMSATS University Islamabad(CUI)Islamabad 45550Pakistan Centre of Agricultural Biochemistry and Biotechnology(CABB) University of AgricultureFaisalabad 38000Pakistan Department of Plant Breeding and Genetics University of AgricultureFaisalabad 38000Pakistan Department of Biotechnology Faculty of Life SciencesUniversity of Central PunjabLahore 54000Pakistan Wheat Research Institute Ayub Agricultural Research Institute(AARI)Faisalabad 38950Pakistan

Stripe rust is a continuous threat to wheat crop all over the *** causes considerable yield losses in wheat crop every *** deployment of adult plant resistance(APR)genes in newly developing wheat cultivars is the most judicious strategy to combat this ***,we dissected the genetics underpinning stripe rust resistance in Pakistani wheat *** association panel of 94 spring wheat genotypes was phenotyped for two years to score the infestation of stripe rust on each accession and was scanned with 203 polymorphic *** on D’measure,linkage disequilibrium(LD)exhibited between loci distant up to 45 c ***-trait associations(MTAs)were determined using mixed linear model(MLM).Total 31 quantitative trait loci(QTLs)were observed on all 21 wheat *** QTLs were newly discovered as well as 19 QTLs and 35 previously reported Yr genes were validated in Pakistani wheat *** major QTLs were ***.2 AL and ***.3 BS(PVE,11.9%).Dissection of genes from the newly observed QTLs can provide new APR genes to improve genetic resources for APR resistance in wheat crop.

关键词： wheat Puccinia striiformis LD GWAS MTA PCoA

Microwave promoted synthesis of some N-(4-methyl-3-tolylthiazol-2(3H)-ylidene)substituted benzamides

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Chinese Chemical Letters 2009年第9期20卷 1073-1076页

作者： Aamer saeed Department of Chemistry Quaid-I-Azam UniversityIslamabad 45320 Pakistan

N-（4-Methyl-3-tolylthiazol-2（3H）-ylidene） substituted benzamides （2a-o） were synthesized in good to excellent yields by the base-catalyzed direct cyclization of corresponding 1-tolyl-3-aryl thioureas （la-o） with 2-bromoacetone through microwave irradiation in a solvent-free medium. Compared to traditional thermal heating, microwave irradiation provides a much more cleaner, efficient and faster method for synthesis of the title compounds. 2009 Aamer saeed. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： 2-Imino-l,3-thiazoline Green synthesis Microwave-accelerated

An Efficient Cyber Security and Intrusion Detection System Using CRSR with PXORP-ECC and LTH-CNN

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Computers, Materials & Continua 2023年第8期76卷 2061-2078页

作者： Nouf saeed Alotaibi Department of Computer Science College of Science and Humanities Al DawadmiShaqra UniversityShaqra11961Saudi Arabia

Intrusion Detection System(IDS)is a network security mechanism that analyses all users’and applications’traffic and detectsmalicious activities in *** existing IDSmethods suffer fromlower accuracy and lack the required level of security to prevent sophisticated *** problem can result in the system being vulnerable to attacks,which can lead to the loss of sensitive data and potential system ***,this paper proposes an Intrusion Detection System using Logistic Tanh-based Convolutional Neural Network Classification(LTH-CNN).Here,the Correlation Coefficient based Mayfly Optimization(CC-MA)algorithm is used to extract the input characteristics for the IDS from the input ***,the optimized features are utilized by the LTH-CNN,which returns the attacked and non-attacked *** that,the attacked data is stored in the log file and non-attacked data is mapped to the cyber security and data security *** prevent the system from cyber-attack,the Source and Destination IP address is converted into a complex binary format named 1’s Complement Reverse Shift Right(CRSR),where,in the data security phase the sensed data is converted into an encrypted format using Senders Public key Exclusive OR Receivers Public Key-Elliptic Curve Cryptography(PXORP-ECC)Algorithm to improve the data *** Security Laboratory-Knowledge Discovery inDatabases(NSLKDD)dataset and real-time sensor are used to train and evaluate the proposed *** suggested model is evaluated based on accuracy,sensitivity,and specificity,which outperformed the existing IDS methods,according to the results of the experiments.

关键词： Intrusion detection system logistic tanh-based convolutional neural network classification(LTH-CNN) correlation coefficient based mayfly optimization(CC-MA) cyber security

On subsurface box-shaped lined tunnel under incident SH-wave propagation

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 948-960页

作者： Mehdi PANJI saeed MOJTABAZADEH-HASANLOUEI Department of Civil Engineering Zanjan BranchIslamic Azad UniversityZanjan45156-58145Iran

In this paper,a half-plane time-domain boundary element method is applied to obtain the seismic ground response,including a subsurface box-shaped lined tunnel deployed in a linear homogenous elastic medium exposed to obliquely incident *** the boundary around the tunnel is required to be *** prepare an appropriate model by quadratic elements,a double-node procedure is used to receive dual boundary fields at corners as well as change the direction of the normal *** encoding the method in a previously confirmed computer program,a numerical study is carried out to sensitize some effective parameters,including frequency content and incident wave angle for obtaining a surface *** depth and impedance ratio of the lining are assumed to be *** responses are illustrated in the time and frequency domains as two/three-dimensional *** results showed that subsurface openings with sharp corners distorted the propagation path of the anti-plane waves to achieve the critical states on the ground *** present approach can be proposed to civil engineers for preparing simple underground box-shaped models with angular boundaries.

关键词： box-lined tunnel half-plane BEM surface response SH-wave time-domain

A novel approach for constructing a 3D model based on registering a mono image on a 3D model, applicable in Digital Earth

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International Journal of Digital Earth 2012年第2期5卷 91-105页

作者： Amir saeed Homainejad Independent Research Group on Geospatial TehranIran

The effect of Digital Earth on our life is *** and updating Geospatial data in Digital Earth is also *** paper presents the application of a new approach of image registration in Digital *** approach was developed based on registering a mono photograph on a master 3D *** result is a 3D vector model,which can be broadly applied in visualisation,mapping,geographic information system(GIS),planning,change detection,as well as Digital *** approach does not require parameters of correction for *** accuracy of the output depends on the accuracy of the master *** approach is very versatile and able to register any image on the digital elevation model,digital surface model and topographic 3D model.

关键词： Digital Earth image registration 3D model