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Physical and mechanical properties of hydroponic lettuce for automatic harvesting

Information Processing in Agriculture 2021年第4期8卷 550-559页

作者： Wenqi Wang Yidong Ma Longsheng Fu Yongjie Cui Yaqoob majeed College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYangling 712100China Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Service Yangling 712100China College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003China Centre for Precision and Automated Agricultural Systems Washington State UniversityProsserWA 99350USA

To design an automatic harvesting machine for hydroponic lettuce(Lactuca sativa L.),physical and mechanical properties of hydroponic lettuce were investigated and *** content of stem,root and leaf,geometric characteristics,pulling force,and root cutting force were studied for harvesting hydroponic *** pulling force was examined by a tensile experiment,while the root cutting force was investigated by a shear experiment on the electronic universal testing *** moisture content of hydroponic lettuce was obtained by direct *** data were processed using regression analysis and mathematical statistics method.A regression equation and the law of numerical distribution were *** results showed that the geometric size of different hydroponic lettuce had little difference,and the distribution of physical parameters was *** content was found statistically similar in stem and root(around 91%),while the highest moisture content was found in the leaf of 95.73%.The root cutting force decrease with the increase of cutting speed and decrease with the cutting position move *** minimum average root cutting force in the experiment was 1.41 *** average pulling force was 13 *** study provides adequate theoretical support for the design of the automatic harvesting machine of hydroponic lettuce.

关键词： Greenhouse vegetable Harvester Variance analysis Response surface

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Investigating the influence of gamma ray energies and steel fiber on attenuation properties of reactive powder concrete

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Nuclear Science and Techniques 2017年第10期28卷 113-120页

作者： Shatha D.Mohammed Wasan Z.majeed Nesreen B.Naji Nada Mahdi Fawzi Department of Civil College of EngineeringUniversity of BaghdadBaghdadIraq Department of Physics College of ScienceUniversity of BaghdadBaghdadIraq

The effect of gamma ray energies and volume ratio of micro steel fiber(1 and 1.5%) on attenuation properties of reactive powder concrete(70 MPa compressive strength) was investigated. Different characteristics have been considered such as linear attenuation coefficient,mass attenuation coefficient, and half-value *** iodide crystal with a gamma ray spectrometer and collimated beam of gamma ray has been implemented to perform the experimental test. Three sources(Cs-137, Co-60, and Bi-207) with energies of(0.662, 1.17 1.33, 0.569,and 1.063) MeV were adopted in the test. The results obtained indicated that mass attenuation coefficient is proportioned inversely with gamma ray energies and directly with a volume ratio of micro steel fiber. The linear attenuation coefficient and half-value thickness of the tested samples have been calculated and discussed. The obtained results showed that increasing the volume ratio of steel fiber has modified the adequacy of the reactive powder concrete as a shielding element since it increases the density and reduces the half-value thickness.

关键词：活性粉末混凝土衰减特性射线能量钢纤维性能影响线性衰减系数质量衰减系数纤维体积比

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Formation of crystalline particles from phase change emulsion： Influence of different parameters

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Chinese Journal of Chemical Engineering 2016年第7期24卷 929-936页

作者： Javed Iqbal Zulfiqar Ali Murid Hussain Rizwan Sheikh Khaliq majeed Asad Ullah Khan Joachim Ulrich COMSATS Institute of Information Technology Department of Chemical Engineering Defence Road Off Raiwind Road Lahore Pakistan Martin-Luther-Universitat Halle-Wittenberg Zentrum fur Ingenieurwissenschaften Verfahrenstechnik/TVT D-06099 Halle (Saale) Germany

Solidification or crystallization of phase change emulsion in the form of fine emulsion drops in a direct contact coolant at temperatures below their freezing point was studied. This work is mainly focused on the size and shape of the generated particles from phase change emulsified fats. Size of the particles is the major or key factor being considered during their formation, however, other factors that govern the particle size and shape were also observed. The operating parameters of the process were optimized in order to obtain particles of smaller size ranges in the window of current operating conditions. The crystallization of complex emulsion matrices is very difficult to control in the bulk at desired requirement. Hence, the emulsion drop to particle formation has advantage in comparison with the bulk solidification or crystallization. The main objective of this work is to achieve spherical emulsion particles in a direct contact cooling system. Parameters like: stability, characterization, viscosity, and the effect of different energy inputs were examined. Moreover, the effects of the capillary size, interfacial tension, temperature of the emulsion on the particle size were also monitored.

关键词：结晶颗粒复合乳液物相变化直接接触颗粒大小操作参数操作条件冷却系统

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Biochemical synthesis of silver nanoprticles using filamentous fungi Penicillium decumbens (MTCC-2494) and its efficacy against A-549 lung cancer cell line

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Chinese Journal of Natural Medicines 2016年第8期14卷 615-620页

作者： Shahnaz majeed Mohd Syafiq bin Abdullah Gouri Kumar Dash Mohammed Tahir Ansari Anima Nanda Faculty of Pharmacy and Health Universiti Kuala Lumpur Royal college of Medicine Ipoh Perak Malaysia 30450 Faculty of Bioscience and chemical Engineering Sathyabama University Rajiv Gandhi Salai Chennai 600119 India

Biosynthesis of silver and other metallic nanoparticles is one of the emerging research area in the field of science and technology due to their potentiality, especially in the field of nano-biotechnology and biomedical sciences in order to develop nanomedicine. In our present study, Penicillium decumbens(MTCC-2494) was brought from Institute of Microbial Technology(IMTECH) Chandigarh and employed for extracellular biological synthesis of silver nanoparticles. Ag-NPs formation was appeared with a dark brown color inside the conical flask. Characterization of Ag-NPs were done by UV-Spectrophotometric analysis which showed absorption peak at 430 nm determines the presence of nanoparticles, Fourier transform infrared(FT-IR) spectroscopic analysis, showed amines and amides are the possible proteins involved in the stabilization of nanoparticles as capping agent. Atomic force Microscopy(AFM) confirmed the particle are spherical, size was around 30 to 60 nm and also the roughness of nanoparticles. Field emission scanning electron microscopy(FE-SEM) showed the topology of the nanoparticles and were spherical in shape. The biosynthesis process was found fast, ecofriendly and cost effective. Nano-silver particle was found to have a broad antimicrobial activity and also it showed good enhancement of antimicrobial activity of Carbenicillin, Piperacillin, Cefixime, Amoxicillin, Ofloxacin and Sparfloxacin in a synergistic mode. These Ag-NPs showed good anti-cancer activity at 80 μg·m L^(-1) upon 24 hours of incubation and toxicity increases upon 48 hours of incubation against A-549 human lung cancer cell line and the synergistic formulation of the antibiotic with the synthesized nanoparticles was found more effective against the pathogenic bacteria studied.

关键词： Silver nanoparticles Penicillium decumbens(MTCC-2494) Antibacterial Anti-cancer

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Specific Capacitance and Cyclic Stability of Graphene Based Metal/Metal Oxide Nanocomposites:A Review

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Journal of Materials Science & Technology 2015年第7期31卷 699-707页

作者： Abdul Waheed Anwar Abdul majeed Nadeem Iqbal Wasi Ullah Ahmad Shuaib Usman Ilyas Fozia Bibi Hafiz Muhammad Rafique Nanotechnologies Research Centre Department of PhysicsUniversity of Engineering and Technology Under Graduate Block/School of Physical Sciences University of the Punjab Department of Physics University of the Punjab

Graphene has become a worldwide admired material among researchers and scientists equally due to its unique richness in mechanical strength, electrical conductivity, optical and thermal properties. Re- searchers have explored that the composite materials based on graphene and metal/metal oxide nanostructures possess excellent potential for energy storage technologies. In particular, supercapacitors based on such composite materials have engrossed the extreme interest of researchers for its rapid charging/discharging time, safe operation and longer cyclic constancy. Till now, several fabrication techniques for composite materials and their energy storage applications have been explored. Here, specially, we have concentrated on the hottest research progress for the fabrication of graphene oxide and metal/metal oxide nanocomposites. We also emphasized on the characteristics and properties of supercapacitors fabricated using these composite materials. Moreover, our study is focused on the specific capacitance and cyclic stability of various composites to haul out the most efficient material for supercapacitor applications.

关键词： GrapheneMetal/metal oxide nanostructureSupercapacitor

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Impact of renewable power market penetration on coal power generation capacity growth

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Journal of Coal Science & Engineering(China) 2011年第2期17卷 217-224页

作者： ABDUL majeed Aziz R. Larry Grayson VLADISLAV Kecojevic The Pennsylvania State University（University Park） 16802 USA West Virginia University Morgantown WV26506-6070 USA

Since renewable energy sources are growing in importance, how well they can penetrate the energy market for power generation will be a very important factor in the role the coal industry will play in the future. This paper examined the displacement of coal power plant capacity from 2010 to 2050 by renewables with respect to three drivers assumed under various conditions: the American Recovery and Reinvestment Act (ARRA), Greenhouse Gas (GHG) policy, and varying plant capital cost cases. The results by 2050 illustrate that renewable market penetration captures anywhere from 1.9% to 6.4% of potential coal power generation capacity additions. Renewable power generation capacity additions is expected to outpace coal power plant additions by 89% with respect to ARRA in 2050, however with no GHG policy coal power generation capacity build-outs will outpace renewables by as high as 809%. Finally, coal power generation is still projected to be the largest single energy source contributor to the electricity market making up 28.0% of total available capacity, while renewables are expected to only make up 16.3% of total available capacity.

关键词：可再生能源发电能力煤炭行业能源市场渗透温室气体排放燃煤电厂资本成本

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Bond-selective transient phase imaging via sensing of the infrared photothermal effect

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Light(Science & Applications) 2019年第1期8卷 70-81页

作者： Delong Zhang Lu Lan Yeran Bai Hassaan majeed Mikhail E.Kandel Gabriel Popescu Ji-Xin Cheng Department of Biomedical Engineering Boston UniversityBostonMA 02215USA Department of Physics Zhejiang UniversityHangzhou 310028China National Laboratory on High Power Laser and Physics Shanghai 201800China Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Department of Bioengineering University of Illinois at Urbana-ChampaignChampaignIL 61801USA Department of Electrical and Computer Engineering University of Illinois at Urbana-ChampaignChampaignIL 61801USA Department of Electrical&Computer Engineering Boston UniversityBostonMA 02215USA Photonics Center Boston UniversityBostonMA 02215USA

Phase-contrast microscopy converts the phase shift of light passing through a transparent specimen,e.g.,a biological cell,into brightness variations in an *** ability to observe structures without destructive fixation or staining has been widely utilized for applications in materials and life *** these advantages,phase-contrast microscopy lacks the ability to reveal molecular *** address this gap,we developed a bond-selective transient phase(BSTP)imaging technique that excites molecular vibrations by infrared light,resulting in a transient change in phase shift that can be detected by a diffraction phase *** developing a time-gated pump-probe camera system,we demonstrate BSTP imaging of live cells at a 50 Hz frame rate with high spectral fidelity,sub-microsecond temporal resolution,and sub-micron spatial *** approach paves a new way for spectroscopic imaging investigation in biology and materials science.

关键词： transient phase utilized

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Broadband THz absorption spectrometer based on excitonic nonlinear optical effects

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Light(Science & Applications) 2019年第1期8卷 922-926页

作者： Avan majeed Pavlo Ivanov Benjamin Stevens Edmund Clarke Iain Butler David Childs Osamu Kojima Richard Hogg Department of Electronic and Electrical Engineering University of SheffieldSheffield S14DEUK School of Engineering University of GlasgowGlasgow G128LTUK EPSRC National Centre for Ⅲ-Ⅴ Technologies University of SheffieldBroad LaneSheffield S37HQUK Department of Electrical and Electronic Engineering Graduate School of EngineeringKobe University1-1 RokkodaiNadaKobe 657-8501Japan

A broadly tunable THz source is realized via difference frequency generation,in which an enhancement to χ^((3)) that is obtained via resonant excitation of III–V semiconductor quantum well excitons is *** symmetry of the quantum wells(QWs)is broken by utilizing the built-in electric-field across a p-i-n junction to produce effectiveχ(2)processes,which are derived from the high χ^((3)).This χ^((2)) media exhibits an onset of nonlinear processes at~4Wcm−2,thereby enabling area(and,hence,power)scaling of the THz *** matching is realized laterally through normal incidence *** two collimated 130mW continuous wave(CW)semiconductor lasers with ~1-mm beam diameters,we realize monochromatic THz emission that is tunable from 0.75 to 3 THz and demonstrate the possibility that this may span 0.2-6 THz with linewidths of ~20 GHz and efficiencies of ~1×10^(-5),thereby realizing ~800 nW of THz ***,transmission spectroscopy of atmospheric features is demonstrated,thereby opening the way for compact,low-cost,swept-wavelength THz spectroscopy.

关键词： tunable thereby nonlinear

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Varying Track Etch Rates along the Fission Fragments＇ Trajectories in CR-39 Detectors

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Chinese Physics Letters 2010年第5期27卷 76-79页

作者： N. All E. U. Khan A. Waheed S. Karim F. Khan A. majeed DPAM PLEAS P.O. Nilore Islamabad Pakistan P.D PINSTECH P.O. Nilore Islamabad Pakistan International Islamic University Islamabad Pakistan Department of Physics CIIT Islamabad Pakistan

We determine the behavior of track etch rate VT along the tracks in CR-39 detectors exposed to fission fragments from ^252Cf source. CR-39 detectors are etched at 70℃ in different concentrations of Na2COa-mixed 6M NaOH solutions for different etching time intervals of 5-10min starting from 15 min up to 210min. Two values of track etch rate are determined along the fission fragment trajectories. The variation in VT is correlated with the energy loss rate of the fission fragment in the detector material.

关键词： track etch etch rate rate

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Characterization and identification of leaf morphology of Populus deltoides Bartr. clones

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Forestry Studies in China 2011年第4期13卷 270-275页

作者： Ajaz LONE Altamah BASHIR Salil K. TEWARI Mumtaz majeed Faculty of Plant Breeding and Genetics Sher-e-e-Kashmir University of Agricultural Sciences & Technology of Kashmir Faculty of Forestry Sher-e-e-Kashmir University of Agricultural Sciences & Technology of Kashmir Department of Silviculture G.B. Pant University of Agriculture and Technology

Leaves are of fundamental importance to plants, representing their facility to generate power and are the sensing units of plants towards the environment. An attempt was made to characterize and compare the variations of leaf morphology of various Populus deltoides Bartr. clones by studying the winter buds and other leaf parameters of fully developed leaves. To achieve these objectives, forty-three exotic and indigenous clones ofP. deltoides Bartr. were evaluated for different parameters. On the basis of various morphological characteristics the results reveal that each clone has a distinct color pattern of leaves. Different colors observed in these clones varied from light green through green to dark green. Two distinct lengths of the leaf apex were found, i.e., short and long; as well both acuminate and acute apex types were found. Erratic distribution of serration of leaves was also found. In this study, the morphological traits of leaves provided discriminatory grounds for separating various populations of P. deltoides Bartr. clones. Winter bud studies indicate that different clones vary considerably with regard to shape, color, shape of leaf scars and exudation.

关键词： Populus deltoides Bartr. leaves morphology winter buds

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