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201.
202.
Industry 4.0 is a buzzword in current research and in the manufacturing environment. However, despite this limited research has focused on how a company can determine the likely benefits of Industry 4.0 technologies and its influence on the supply chain. Additionally, the aspect of customer experience is gaining significant importance in the new Industry 4.0 supply chain. There is a research gap in implementation strategies of Industry 4.0 concepts for small and medium sized enterprises (SMEs). This paper addresses this gap through an in-depth case study of an SME and highlights how the company can develop competitive advantage. First, a framework was developed to determine the realization of Industry 4.0 predicted benefits for SMEs, which was tested in a case company. Based on input from the case the five-step framework for Industry 4.0 realization is adjusted. It enables practitioners to determine the actual status for their company towards Industry 4.0 realization and thereby functions as a guide for further implementation strategies. 相似文献
203.
H.M.S. Iqbal S. Bhowmik J.A. Poulis R. Benedictus 《Polymer Engineering and Science》2010,50(8):1505-1511
This investigation highlights the adhesion performance of carbon fiber‐ and glass fiber‐reinforced polyphenylene sulfide when joined by high‐performance neat epoxy adhesive and nanofilled epoxy adhesive. A significant increase in the surface energy of these materials is observed after the surface modification with atmospheric plasma treatment. An increase in surface roughness is observed after exposing the surface to plasma. Lap shear testing of untreated and plasma‐treated joints is carried out to correlate the improvement in adhesion properties with the joint strength. A considerable increase in joint strength is observed when the surfaces of these materials are modified by atmospheric pressure plasma. There is a further increase in joint strength when the composites are joined by nanofilled epoxy adhesive, and subsequent exposure to electron beam radiations results in minor increase in the joint strength. Finally, the fractured surfaces of the joints are examined and the analysis is performed. POLYM. ENG. SCI., 50:1505–1511, 2010. © 2010 Society of Plastics Engineers 相似文献
204.
Mohammad A. Khanfar Diaa T. A. Youssef Prof. Khalid A. El Sayed Prof. 《ChemMedChem》2010,5(2):274-285
The microfilament cytoskeleton protein actin plays an important role in cell biology and affects cytokinesis, morphogenesis, and cell migration. These functions usually fail and become abnormal in cancer cells. The marine‐derived macrolides latrunculins A and B, from the Red Sea sponge Negombata magnifica, are known to reversibly bind actin monomers, forming 1:1 stoichiometric complexes with G‐actin, disrupting its polymerization. To identify novel therapeutic agents for effective treatment of metastatic breast cancer, several semisynthetic derivatives of latrunculin A with diverse steric, electrostatic, and hydrogen bond donor and acceptor properties were rationally prepared. Analogues were designed to modulate the binding affinity toward G‐actin. Examples of these reactions are esterification, acetylation, and N‐alkylation. Semisynthetic latrunculins were then tested for their ability to inhibit pyrene‐conjugated actin polymerization, and subsequently assayed for their antiproliferative and anti‐invasive properties against MCF7 and MDA‐MB‐231 cells using MTT and invasion assays, respectively. 相似文献
205.
Karim Chkirate Gamal Al Ati Khalid Karrouchi Saad Fettach Hind Chakchak Joel T. Mague Smaail Radi N. N. Adarsh My El Abbes Faouzi El Mokhtar Essassi Yann Garcia 《Chembiochem : a European journal of chemical biology》2023,24(20):e202300331
Three dinuclear coordination complexes generated from 1-n-butyl-2-((5-methyl-1H-pyrazole-3-yl)methyl)-1H-benzimidazole ( L ), have been synthesized and characterized spectroscopically and structurally by single crystal X-ray diffraction analysis. Reaction with iron(II) chloride and then copper(II) nitrate led to a co-crystal containing 78 % of [Cu(NO3)(μ-Cl)( L’ )]2 ( C1 ) and 22 % of [Cu(NO3)(μ-NO3)( L’ )]2 ( C2 ), where L was oxidized to a new ligand L’ . A mechanism is provided. Reaction with copper chloride led to the dinuclear complex [Cu(Cl)(μ-Cl)( L) ]2 ( C3 ). The presence of N−H⋅⋅⋅O and C−H⋅⋅⋅O intermolecular interactions in the crystal structure of C1 and C2 , and C−H⋅⋅⋅N and C−H⋅⋅⋅Cl hydrogen bonding in the crystal structure of C3 led to supramolecular structures that were confirmed by Hirshfeld surface analysis. The ligands and their complexes were tested for free radical scavenging activity and ferric reducing antioxidant power. The complex C1 / C2 shows remarkable antioxidant activities as compared to the ligand L and reference compounds. 相似文献
206.
Heavy duty gas turbine power plants may cause severe instability in grid connected operation under load fluctuations. To overcome such instability problems, an attempt has been made to develop proportional-integral-derivative controller for all the heavy duty gas turbine models with Speedtronic governor. Proportional-integral-derivative gains are tuned by Ziegler-Nichols and performance index methods and the step responses are obtained by using MATLAB/Simulink considering various droop settings. Simulation results of all the models reveal that the integral of squared error tuned proportional-integral-derivative controller provide better response. In order to improve the stability further, fuzzy self-tuning proportional-integral-derivative controller has been proposed in this article for all the heavy duty gas turbine models. On analyzing the simulation results, the proposed fuzzy self-tuning proportional-integral-derivative controller is found to be adaptive for all the heavy duty gas turbine models irrespective of the droop settings and yield better transient and steady state responses than Ziegler Nichols and Performance index methods. 相似文献
207.
A new distance-relaying algorithm for single-phase-to-ground faults on series-compensated parallel transmission lines is proposed in this article. Fault impedance can be calculated using this algorithm without any parameters requirement of mutual coupling and series capacitor device (series capacitor/metal oxide arrestor/discharging gap). The series capacitor device is simplified as linearized impedance during faults. The parameters of mutual coupling and a series capacitor device can be used as variables in the fault loop equations. Real-time digital simulator tests show that the proposed distance-relaying algorithm can obtain more accurate results than traditional distance-relaying algorithms for series-compensated parallel transmission lines. 相似文献
208.
Analysis of cooling curve to determine the end point of freezing 总被引:1,自引:0,他引:1
M. Shafiur Rahman Nejib Guizani Mohammed Al-Khaseibi Salim Ali Al-Hinai Salha Saleh Al-Maskri Khalid Al-Hamhami 《Food Hydrocolloids》2002,16(6):111
The cooling curve method used for the measurement of freezing point of food is further analyzed to explore whether it can be used to identify the end point of freezing or glass transition. In this method, slope of the cooling curve is determined and plotted as a function of time to identify the end point of freezing (T′m). Initially, the slope is decreased and then reached a minimum value, which is identified as the nucleation of ice. Then the slope is increased until the end point of freezing. The end point of freezing is identified when the slope starts to decrease from its highest value or plateau. Sucrose solutions and starch gels were used to measure its T′m in identifying validity of the proposed method. The measured values of T′m by the proposed method is very close to the literature values. 相似文献
209.
Proteins soluble in tris-acetate buffer (pH9.0) were fractionated by DEAE-cellulose, DEAE-Sephadex A-50 and Sephadex G-200 column chromatography. The purified proteins which contained 5–6% carbohydrate, had molecular weights of 125 900 and 22 390 amu. The high molecular weight fraction was homogeneous by polyacrylamide gel electrophoresis. Proteins extracted in phosphate buffer (0.1M , pH7.6) when subjected to Sephadex G-200 gel chromatography were resolved into three fractions, all of which showed considerable trypsin inhibitor activity. Germination for 3 days reduced the trypsin inhibitor activity of the seed by about 30%. 相似文献
210.
Shabnum Shaheen Muhammad Asaf Khan Muhammad Naveed Shahid Zeeshan Shamim Bilal Rasool Khadim Hussain Sana Khalid Nidaa Harun Riffat Siddique Romaisha Sonia Farah Khan 《Microscopy research and technique》2022,85(2):623-629
Present research work was carried out to clarify the variations among species of genus Paspalum morphologically and palynologically as this genus is taxonomically difficult due to having multiple similar morphologically overlapping characters which make it difficult to identify. Henceforth present research work was carried out to delimit taxa within the same genus by morphological and palynological tools through light microscopy (LM) and scanning electron microscopy (SEM). Both these tools are considered as the most useful taxonomic characters for taxonomically problematic genera. The results showed a lot of variations among morphological characters. In Paspalum dilatatum, the upper glume was ovate whereas in the other two species, the upper glume was elliptic. The upper glume apex found in P. dilatatum and Paspalum scrobiculatum was obtuse whereas in Paspalum distichum, upper glume apex was acute. Glume nerves showed variation in all three species. Paspalum distichum was 3 nerved, P. scrobiculatum was 5–7 nerved, and P. dilatatum was 5–9 nerved. All three species showed variation in lemma nerves. Paspalum scrobiculatum had 3 nerved lemma whereas in P. distichum 3–5 nerved and P. dilatatum 5–9 nerved lemma were present. In polar and equatorial view, pollen grains ranged from 25 (20–30) to 37.5 (30–45) μm. Paspalum distichum appeared to be the smallest in size whereas P. dilatatum was the largest. Exine thickness ranged from 0.75 (0.5–1) to 1.35 (1.2–1.5) μm. The higher value of pollen fertility was found in P. scrobiculatum as 87.69% and the lowest value was in P. distichum as 78.08%. Morphological keys were also given for correct identification. 相似文献