Precipitation of Manganese Ammonium Phosphate from Homogeneous Solution by Urea Hydrolysis

352-35

Formation of bi-aryls via a domino palladium catalysis

Synthesis of bi-aryls via a domino Pd-catalyzed reaction of 1-(2-bromophenyl)-2-methylpropan-1-ones/(2-bromophenyl)(cyclohexyl)methanones is presented. The mechanism of the reaction is believed to proceed through a five membered palladacycle that combines with a second molecule of halo-arene to yield the bi-aryls. This method is quite successful to deliver highly sterically crowded bi-aryls with dense functionalities on the aromatic rings

A domino palladium catalysis: Synthesis of 7-methyl-5 H -dibenzo[ a, c ][7] annulen-5-ones

A domino Pd-catalyzed reaction of 1-(2-bromophenyl)ethanones for the synthesis of novel 7-methyl-5H-dibenzo[a,c][7]annulen-5-ones, a carbon core structure present in colchicinoid natural products, is presented. The reaction is proposed to proceed via intermolecular homobiaryl coupling and intramolecular aldol condensatio

Palladium-catalyzed selective α-arylation of ortho -bromoacetophenones

Synthesis of 1-(2-bromophenyl)-2-phenylethanones via an intermolecular Pd-catalyzed α-arylation of 1-(2-bromophenyl)ethanones is presented. The method relies on selective C-H activation (α-arylation) of relatively more reactive external iodo-arenes as coupling partners without affecting the bromo-substituent. Moreover, the scope and generality of the method has been well studied by employing the reaction with iodo-arenes as coupling partners bearing electron-withdrawing, simple, and electron-donating groups on the aromatic ring

CNN Framework for Tumor Classification in MR Brian Images

Deep Learning is the newest and the current trend of the machine learning field that paid a lot of theresearchers' attention in the recent few years. As a proven powerful machine learning tool, deeplearning was widely used in several applications for solving various complex problems that requireextremely high accuracy and sensitivity, particularly in the medical field. In general, the brain tumoris one of the most common and aggressive malignant tumor diseases which is leading to a noticeablyshort expected life if it is diagnosed at a higher grade. Based on that, brain tumor classification is anoverly critical step after detecting the tumor in order to achieve an effective treating plan. In thispaper, we used Convolutional Neural Network (CNN) which is one of the most widely used deeplearning architectures for classifying a dataset of 3064 T1 weighted contrast-enhanced brain MRimages for grading (classifying) the brain tumors into three classes (Glioma, Meningioma, andPituitary Tumor). The proposed CNN classifier is a powerful tool and its overall performance with anaccuracy of 98.93% and sensitivity of 98.18% for the cropped lesions, while the results for theuncropped lesions are 99% accuracy and 98.52% sensitivity and the results for segmented lesionimages are 97.62% for accuracy and 97.40% sensitivity

Direct Torque Control of VSI Fed Induction Motor with Fuzzy Controller

The Direct Torque Control (DTC) methods for AC machines are commonly utilized in many variable speed drives, especially in case the torque control is more desired than speed control. Two major problems that are usually related with DTC drives are: 1) switching frequency that varies with operating conditions and 2) high torque ripple. To solve these problems and at the same time intermit the simple control structure of DTC, a constant switching frequency torque controller is proposed to replace the conventional hysteresis-based controller. The major advantages of the Voltage Source Inverter (VSI) are combines with those of the DTC technique, producing the appropriate voltage vectors under 0.9 input power factor operations. The results prove the high quality and robustness in the system dynamic response and minimize in the both steady-state and transient motor ripple torque. The proposed switching scheme for VSI based DTC of IM drive select the necessary switching vectors for control of torque with small variations of the stator flux within the hysteresis band. This paper presents a novel control scheme based on Fuzzy Logic Controller (FLC). This paper reviews the research and development in direct torque control of VSI fed IM.Such a review helps the highly effective control strategies for AC machine to provide a very fast torque and flux control. In this technical context an overview of VSI fed induction motor has been carried out based on the reports from the literature present in past two recent decades

Treatment of osteonecrosis of femoral head in young patients by surface replacement of femoral head

Background: Osteonecrosis of hip is a pathological condition that affects usually young adults. Articular surface replacement (ASR) is considered to be a viable option in young patients. The study was done with the aim to analyse and to recommend the management of osteonecrosis of femoral head in young patients by surface replacement of femoral head as ideal procedure.Methods: The present study was conducted in 30 patients with osteonecrosis of the femoral head who attended to OPD at Santhiram Medical College and General Hospital, Nandyal, A.P during the period of April 2016 to September 2017. Articular surface replacement of the femoral head was the surgical procedure done in all the patients. The success of the treatment was analysed by Harris hip scoring.Results: Maximum number of patients (60%) was below 40 years of age. Male dominance (77%) was seen in the study. According to Ficat and Arlet classification 12 cases (40%) were under the category of stage II-B and 18 cases (60%) were of stage III. Postoperatively about 90% of patients had postoperative Harris hip score of >80 points. Surgery was succeeded in 10 hips of stage II-B and 15 hips in stage III. According to Harris hip scoring excellent results were obtained in 15 (50%), good in 12 (40%), fair in 2 (6.67%) and poor result 1 (3.3%) patient.Conclusion: The study concludes that the surface replacement is an anatomical hip arthroplasty with preservations of more than 70% of bone stock of femoral head and the ability of the patients to sit cross-legged and squat, which is the desire of the Indian population