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排序方式: 共有490条查询结果,搜索用时 15 毫秒
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Asma Ayaz Wajid Zaman Fazal Ullah Saddam Saqib Shayan Jamshed Saraj Bahadur Abdul Shakoor Bushra Arshad 《Microscopy research and technique》2020,83(1):81-87
In all over the world, herbal drugs are usually adulterated with similar species or varieties due to incorrect identification. Most of herbal products devoid purity and quality, therefore an attempt was carried out to identify plant species and authenticate its herbal drug products from Mentha suaveolens. Microscopy tools provide an excellent platform to identify plants at species level. In this study, microscopic and pharmacokinetic parameters of M. suaveolens were observed. Plant species were collected from high diverse areas of Northern Pakistan. Macro and micro‐morphology including palynology and anatomical features were analyzed to study M. suaveolens. Species characteristics were studied, while implementing microscopic techniques for the delimitation and identification of the species. Traditionally Mentha species are used to cure several diseases that is, digestive disorders, respiratory disorders. Micromorphology (stem, leaves, flowers structure, length etc.), palynology (shape, size of pollen etc.), and anatomical characters (types of stomata, epidermal cell shape, and trichomes) were studied. Micromorphology and anatomical characters were of great interest and significance to discuss the taxonomy of the species. Taxonomic characters were studied to characterize and authenticate the species. The aim of the present study is to observe in detail the taxonomic identification of the species in term of morphology, palynology, and foliar epidermal anatomy for the correct identification along with their medicinal uses in the area. 相似文献
3.
Measurement of Inlet Drop Size Distribution of Secondary Dispersions by Laser Particle Size Analyzer
Knowledge of the Oil drop size distribution, in addition to the mean drop size, is necessary in order to characterize secondary dispersions. Furthermore, the capture efficiency for any drop flowing through a packed bed depends upon its Oil inlet drop diameter. The Oil/Water secondary dispersions produced by the centrifugal pump were analyzed at regular intervals during an experiment to ascertain the drop size distribution and to check that the feed to the coalescence bed was consistent. New techniques that were developed for measurement of drop size distribution of secondary dispersions using Laser Particle Size Analyzer, which consisted of (He/Ne) laser emitter and laser receiver and lenses. The Laser Particle Size Analyzer was fixed directly to the experimental equipment by using the special designed circular cell. The measurement of drop size distribution was done by computer system with application software package. The new mean drop diameter (i.e., d21) equation has been derived theoretically and the results that predicted from this equation exhibited a maximum error of ±15% from the experimental data. 相似文献
4.
Bakos E T Hegedüs Z Holló E Welker GE Tusnády GJ Zaman MJ Flens A Váradi B Sarkadi 《Canadian Metallurgical Quarterly》1996,271(21):12322-12326
The membrane topology of the human multidrug resistance-associated protein (MRP) was examined by flow cytometry phenotyping, immunoblotting, and limited proteolysis in drug-resistant human and baculovirus-infected insect cells, expressing either the glycosylated or the underglycosylated forms of this protein. Inhibition of N-linked glycosylation in human cells by tunicamycin did not inhibit the transport function or the antibody recognition of MRP, although its apparent molecular mass was reduced from 180 kDa to 150 kDa. Extracellular addition of trypsin or chymotrypsin had no effect either on the function or on the molecular mass of MRP, while in isolated membranes limited proteolysis produced three large membrane-bound fragments. These experiments and the alignment of the MRP sequence with the human cystic fibrosis transmembrane conductance regulator (CFTR) suggest that human MRP, similarly to CFTR, contains a tandem repeat of six transmembrane helices, each followed by a nucleotide binding domain, and that the C-terminal membrane-bound region is glycosylated. However, the N-terminal region of MRP contains an additional membrane-bound, glycosylated area with four or five transmembrane helices, which seems to be a characteristic feature of MRP-like ATP-binding cassette transporters. 相似文献
5.
A decision aid for scheduling production in glass fiber manufacturing industry is described. The methodology combines a linear programming (LP) optimization model with a heuristic model. The LP model determines production goals; the heuristic model then uses the LP output to incorporate system-specific constraints in developing processing sequences. 相似文献
6.
Touqeer Haseeb Zaman Shakir Amin Rashid Hussain Mudassar Al-Turjman Fadi Bilal Muhammad 《The Journal of supercomputing》2021,77(12):14053-14089
The Journal of Supercomputing - The Internet of Things is a rapidly evolving technology in which interconnected computing devices and sensors share data over the network to decipher different... 相似文献
7.
Haitham Badi Sabah Hasan Hussein Sameem Abdul Kareem 《Neural computing & applications》2014,25(3-4):733-741
The main objective of this study is to explore the utility of a neural network-based approach in hand gesture recognition. The proposed system presents two recognition algorithms to recognize a set of six specific static hand gestures, namely open, close, cut, paste, maximize, and minimize. The hand gesture image is passed through three stages: preprocessing, feature extraction, and classification. In the first method, the hand contour is used as a feature that treats scaling and translation of problems (in some cases). However, the complex moment algorithm is used to describe the hand gesture and to treat the rotation problem in addition to scaling and translation. The back-propagation learning algorithm is employed in the multilayer neural network classifier. The second method proposed in this article achieves better recognition rate than the first method. 相似文献
8.
Nor?Azowa?IbrahimEmail author Faraj?Abu-Ilaiwi Mohamad?Zaki?Ab.?Rahman Mansor?B.?Ahmad Khairul?Zaman?M.?Dahlan Wan?Md?Zin?Wan?Yunus 《Journal of Polymer Research》2005,12(3):173-179
Grafting of acrylamide (AAm) onto oil palm empty fruits bunch fiber using hydrogen peroxide as initiator and methyl acrylate as comonomer was investigated. The amount of comonomer needed to make grafting of acrylamide possible was determined. The percentage of poly(acrylamide) and the comonomer in the final graft copolymer was estimated by elemental analysis. Results obtained indicated that methyl acrylate facilitated the incorporation of acrylamide monomer onto OPEFB. The reactivity ratios for both monomers were determined by using Fineman–Ross plot. The effects of reaction temperature and period as well as amount of the initiator, solvent, monomer and comonomer on the percentage of grafting at fixed amount of comonomer (11 mmol) were studied. Maximum percentage of grafting was achieved when the amount of initiator and solvent 3.98×10−3 mol and 50 mL respectively. The optimum reaction temperature was 50 ○C and the reaction period was 90 min. Highest percentage of grafting was 232% when 25.6 mmol of acrylamide was used under these optimum conditions. The presence of functional group in the grafted polymer is characterized by infrared spectroscopy and the surface morphology is observed by scanning electron microscopy. Thermoanalytic investigation on OPEFB and OPEFB-g-PAAM were carried out to evaluate the thermal stability and respective activation energy of the materials. 相似文献
9.
Facial features under variant-expressions and partial occlusions could have degrading effect on overall face recognition performance. As a solution, we suggest that the contribution of these features on final classification should be determined. In order to represent facial features contribution according to their variations, we propose a feature selection process that describes facial features as local independent component analysis(ICA) features. These local features are acquired using locally lateral subspace(LLS) strategy.Then, through linear discriminant analysis(LDA) we investigate the intraclass and interclass representation of each local ICA feature and express each feature s contribution via a weighting process. Using these weights, we define the contribution of each feature at local classifier level. In order to recognize faces under single sample constraint, we implement LLS strategy on locally linear embedding(LLE) along with the proposed feature selection. Additionally, we highlight the efficiency of the implementation of LLS strategy. The overall accuracy achieved by our approach on datasets with different facial expressions and partial occlusions such as AR, JAFFE,FERET and CK+ is 90.70%. We present together in this paper survey results on face recognition performance and physiological feature selection performed by human subjects. 相似文献
10.
Babar Zaman Muhammad Riaz Saddam Akbar Abbasi 《Quality and Reliability Engineering International》2016,32(2):663-671
There are two main types of variations, namely, common and special causes leading to in‐control and out‐of‐control states, respectively. Control charts are popular tools used to differentiate between these two states of a process. Implementation of runs rules schemes with control charts is an attractive approach for process monitoring. This study is designed to describe the methodology of runs rules schemes and discuss their implementation for different types of control charts. We have considered memory‐less charts, namely, , S, and R charts for our study purposes. It is examined that the efficiency gain depends on the number of decision points utilized to implement a given rule. Moreover, superiority of runs rules schemes may vary for different types of location and dispersion charts. An application example using a dataset is also included in the study for practical considerations. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献