In this study 0.5LiMn 2 O 3 .0.5LiNi 1/3 Mn 1/3 Co 1/3 O 2 , a layered lithium-manganese rich nickel manganese cobalt (LMR-NMC) oxide, was a carefully selected composition for use as a cathode material in Li ion batteries. The effect of synthesis method and doping on this layered lithium-manganese rich, mixed metal oxides is presented. First part of this study deals with the effect of synthesis route on the electrochemical properties of the 0.5LiMn 2 O 3 .0.5LiNi 1/3 Mn 1/3 Co 1/3 O 2 material. A comparison between Co- precipitation, low temperature (90°C) sol-gel synthesised and high temperature (120°C) sol- gel synthesised LMR composite materials is presented. The study demonstrated that synthesis procedure and conditions strongly influence the electrochemical properties of the synthesized material. Co-precipitation and sol-gel synthesised LMR composites revealed obvious differences in capacity and cycle life, which give the impression from X-ray photoelectron spectra to be strongly related to the particles‘ surface reactivity. In the second part of study, the LMR-NMC materials were doped with varying amounts of aluminium. Small amounts of Al doping to the sol-gel material were shown to improve the rate capability and cyclability, in addition to decreasing voltage fade. The results were interpreted in terms of charge discharge studies and supported by differential capacity plots, impedance measurements and cyclic voltammetry data. The electrochemistry of an aluminium doped material was revealed to be highly dependent on the degree of aluminium doping – with the behaviour of 1% doped material giving a maximum capacity of 201 mAhg -1 at 150 mAg -1 and a capacity retention of 88% after 200 cycles. An attempt has been made to study the effect of Cr doping as well on the electrochemical properties of the LMR-NMC materials. It results in an increase in the initial charge/discharge capacity of the material while decreasing the capacity retention. However, the Cr as a dopant could not be assigned as an improvement in the LMR mixed metal oxide material. The study established the comparative role of co-precipitation and sol-gel methods on the improvement of electrochemical properties of the LMR-NMC oxides. Additionally, controlled Al doped samples substantially improved the discharge capacity while maintaining capacity retention event at very high C-rate.
جبر پر جو کتاب لکھوں گا پیار میں انتخاب لکھوں گا بے بسی دیکھ کر میری تو نے درد کو لذتوں کا رنگ دے کر حکم آیا غبار راہ ہو جا ہر ادا خود میں سمو لیتا ہے پھرے اویس آزردہ و آوارہ سا
صرف تم ،انتساب لکھوں گا تیری ایک ایک بات لکھوں گا جو کیا احتساب لکھوں گا وہی ہے امر خواب لکھوں گا بند قسمت کا باب لکھوں گا شیشہ بے حجاب لکھوں گا ہونگے وہ بھی بیتاب لکھوں گا
Former Egyptian Muḥaddithīn of the each centuries have played a well-regarded, venerated and esteemed role in services of Ḥadīth and its sciences. Their outstanding contribution in this regard has been appreciated in each century of Islamic history. Those Muḥaddithīn have left valuable work on Ḥadīth and its sciences in their popular and basic sources of Ḥadīth for coming generations. Muḥaddithīn of 20th century were not less than the former in their involvement in the field of Hadith. Their dynamic and marvelous efforts are needed to be unveiled for scholars and students of Ḥadīth. Al-shaykh Abdur Raḥmān al Banna Al sāʻātī is known as one of the prominent Egyptian Muḥaddithīn in 20th century. He made extraordinary efforts in the field of Ḥadīth and its sciences through compiling and writing various remarkable books in this regard. His marvelous work in Alfatḥ Al-Rabbānī li Tartīb Musnad Al-Imām Aḥmad bin Hanbal Al-Shaybānī on Musnad Imām Aḥmad bin Hanbal in its rearranging, categorizing and organizing its Ḥadīth is deserved to be cherished and focused on due to its significance and importance in the field of Ḥadīth. He is the first Muḥaddith who presented the Aḥādīth of Musnad in seven outstanding chapters to facilitate the researchers in their accessing to the main theme of the Musnad. In this paper the life sketch of Al-Shayk Abdur Raḥmān, his scholarly contribution in the field of Ḥadīth and his methodology in his renowned book alfatḥ al-Rabbānī has been discussed and highlighted its valuable aspects.
Background: Preoperative anxiety is a common perioperative complication, according to studies done it is seen in approximately 11-80% of adults undergoing surgery. Various pharmacological and non pharmacological techniques have been used to reduce preop anxiety. One of the goals of the preanaesthesia clinic is to allay anxiety. Literature shows that a preanaesthesia clinic evaluation reduces anxiety however b current studies done on anxiety and the preanaesthesia clinic have not quantified this reduction. Objective: To determine the reduction in anxiety in patients evaluated in the clinic versus those evaluated in the ward. Study Design: A cohort and before – after study Setting: The surgical outpatient clinics, the gynaecological outpatient clinic, the antenatal clinic, the wards and operating theatres at the Aga Khan University Hospital, Nairobi. Population: All the adult patients scheduled for non-cardiac elective surgical procedures during the study period. Sample size: 44 adult patients with 22 patients in each of the 2 groups i.e. anaesthesia clinic (AC) group and the ward group (W). Methods: 51 adult patients with 28 patients in anaesthesia clinic group and another 23 in the ward were sequentially recruited from both the surgical outpatient clinic, gynaecology outpatient clinic and antenatal clinic. The patient’s State Trait Anxiety Index (STAI) was taken once the patient was booked for theatre. The patient then had a preanaesthesia evaluation either in the preanaesthesia outpatient clinic (PAC) or in the wards. Another STAI score was taken in the preoperative area in theatre on the day of surgery. The patients were then traced back as to whether they had their intervention in the ward or the clinic and hence divided into two groups. The difference in the change of STAI scores in both groups was then analysed. Results: 51 adult patients were recruited i.e. 28 in the clinic group and 23 in the ward group. The majority of the recruited patients were female (n=38). Statistically significant difference was seen in the reduction of the anxiety scores between the clinic group 2.143(C.I=1.384-2.902) and ward group 0.739(C.I=0.168-1.311) with a p value=0.0051.There was also significant difference in reduction in anxiety scores within ward group in the patients with no prior anaesthetic experience having a greater reduction than those a prior anaesthetic experience. There were no other significant differences between the 2 groups. Conclusion: Patients evaluated in the anaesthesia clinic had a greater reduction in their anxiety but it was not as much as hypothesised which may