Teleparallel Energy-momentum Distribution of Locally Rotationally Symmetric Spacetimes

M. Jamil Amir,Tahir Nazir 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.9

In this paper, we explore the energy-momentum distribution of locally rotationally symmetric(LRS) spacetimes in the context of the teleparallel theory of gravity by considering the three metrics,I, II and III, representing the whole class of LRS sapcetimes. In this regard, we use the teleparallelversions of the Einstein, Landau-Lifshitz, Bergmann-Thomson, and M¨oller prescriptions. Theresults show that the momentum density components for the Einstein, Bergmann-Thomson, andM¨oller prescriptions turn out to be same in all cases of the metrics I, II and III, but are differentfrom those of the Landau- Lifshitz prescription, while the energy components remain the same forthese three prescriptions only in all possible cases of the metrics I and II. We mention here thatthe M¨oller energy-momentum distribution is independent of the coupling constant ; that is, theseresults are valid for any teleparallel models.

PRODUCTION PERFORMANCE AND MILK PRODUCING EFFICIENCY IN DIFFERENT FILIAL GROUPS OF H. FRIESIAN × SAHIWAL HALFBREDS

Chaudhry, M.Z.,Tahir, M.J.,Rafique, M. Asian Australasian Association of Animal Productio 1994 Animal Bioscience Vol.7 No.3

Six heifers each of $F_1$, $F_2$, $F_3$, $F_4$ H. Friesian $\times$ Sahjwal halfbreds and pure Sahiwal with overall average initial age and live weight of $315.6{\pm}134.8 days$ and $143.8{\pm}48.5kg$, respectively were used for this study. The under trial animals were fed according to N.R.C. (1978). The overall average age at maturity, first conception and first calving was $563.8{\pm}116.8$, $675.8{\pm}135.6$ and $956.8{\pm}149.8days$ with live weights as $302.2{\pm}58.6$, $342.6{\pm}41.5$ and $433.9{\pm}38.1kg$, respectively. The overall 305 days and total milk yield for 1st lactation was $2,729.0{\pm}669.3$ and $2,992.7{\pm}377.5litre$ while the FCM (at 4%) was $2,934.2{\pm}410.8litre$. The lactation length was $336.6{\pm}69.6days$. The fat and solids not fat contents were $4.5{\pm}0.2$ and $8.2{\pm}0.3percent$, respectively. The milk production in Sahiwal cows was significantly lower than crossbred cows. The services per conception were $2.5{\pm}1.3$. The overall per head per day consumption of DM, TCP and ME was $10.9{\pm}1.2kg$, $1,399{\pm}199gm$ and $22.6{\pm}2.4 M.Cal.$, respectively. The overall milk producing efficiency for the production of one litre of FCM was $1.12{\pm}0.15kg$ of DM, $142.2{\pm}17.76gm$ of TCP and $2.31{\pm}0.27M.Cal.$ of energy while the feeding cost was Rs. $1.46{\pm}0.22$ per litre of FCM produced. The feeding cost per litre FCM was significantly higher in Sahiwal and $F_2$ than in other genetic groups.

Polyaniline-engineered zinc sulphide nanocomposite as a highly efficient electrocatalyst for the oxygen evolution process

Alenad Asma M.,Fatima Sofia,Khalid Usman,Bano Nigarish,Abid Abdul Ghafoor,Manzoor Sumaira,Farid Hafiz Muhammad Tahir,Messali Mouslim,Alzahrani Huda A.,Taha Taha Abdel Mohaymen 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.5

Hydrogen is the ideal future fuel, since it is clean, saves energy, and is abundant in nature. Though there are several methods for producing hydrogen, only a few of them are environmentally friendly. To employ water electrolysis to make hydrogen and solve the energy shortage problem, highly active electrocatalysts must be created. Zinc sulphide/polyaniline (ZnS/PANI) nanocomposite was successfully produced using a straightforward two-step coprecipitation and polymerization procedure. Different analyses were used to characterize the fabricated materials. The findings show that the ZnS/PANI nanocomposite's morphology has a consistent porous shape, and the electrical structure of the active sites determines how well catalysts can make contact with the intermediates. Multiple attempts have been made to create the most affordable, functional electrocatalyst for oxygen evolution reactions (OER). However, clean energy production from such materials is sluggish. In comparison to pure PANI nanofibers (143.14 m2 g−1 and 0.4827 nm) and ZnS nanostructures (249.85 m2 g−1 and 0.4224 nm), the composite ZnS/PANI displays a greater Brunauer–Emmett–Teller (BET) surface area around 372.65 m2 g−1 along with nanoporous size of 0.393 nm due to the interaction, which provides distinctive features in contrast to ZnS and PANI. Synergistically, composite ZnS/PANI indicates lower overpotentials of 132 mV for oxygen evolution performance at 10 mA cm−2. An improved OER activity is observed by composite ZnS/PANIs as high current density, lower overpotential and reduced Tafel value of 53 mV dec−1. This catalyst also exhibited a significant double-layer capacitance and a large electrochemically active surface area. ZnS/PANI is a magnificent electrocatalyst for oxygen evolution.

Morphology controlled facile synthesis of MnO2 adsorbents for rapid strontium removal

Umar Asim,Syed M. Husnain,Naseem Abbas,Faisal Shahzad,Abdul Rehman Khan,Tahir Ali 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.98 No.-

MnO2 nanostructures with three distinct architectures, namelyflower, balk and tube-like, have beensynthesized through a single step microwave assisted hydrothermal method at different reactiontemperatures (110 C, 140 C and 180 C). The characterization of as prepared MnO2 samples wereperformed by means of Fourier transform infrared spectroscopy, X-ray diffraction, scanning electronmicroscopy, and transmission electron microscopy. The N2 adsorption–desorption isotherms revealedthe higher specific surface area and porosity of theflower like MnO2 as compared to balk and tube-likeMnO2. The adsorption behavior of as prepared adsorbents was investigated towards Sr2+ radionuclide. Because of the hierarchal structure and the high surface area (62.64 m2/g), MnO2-110 depicted the bestSr2+ adsorption performance with maximum adsorption capacity of 52 mg/g at pH 6 as compared to otherMnO2 morphologies synthesized at 140 C and 180 C. The kinetic studies revealed that the adsorption ofSr2+ onto MnO2-110 followed the pseudo-first-order model whereas the adsorption equilibrium dataobeyed the Freundlich and Sips model. Moreover, the MnO2-110 adsorbent reached the steady statequickly ( 10 min) and is capable to bind Sr2+ in slightly acidic to alkaline solutions.

A STUDY ON ESTIMATION OF HERITABILITY OF BIRTH WEIGHT AND WEANING WEIGHT OF TEDDY GOATS KEPT UNDER PAKISTANI CONDITIONS

Tahir, M.,Younas, M.,Raza, S.H.,Lateef, M.,Iqbal, A.,Raza, P.N. Asian Australasian Association of Animal Productio 1995 Animal Bioscience Vol.8 No.6

The mean birth weight and weaning weight estimated from 777 kids from 30 bucks of Teddy goats were $1.67{\pm}0.31$ and $8.50{\pm}2.18kg$, respectively. The estimates of heritability of birth weight and weaning weight by half sib correlation method were $0.048{\pm}0.022$ and $0.101{\pm}0.012kg$, respectively. The high heritability estimates of birth weight indicates that selection on the basis of individual's own record will be effective. The low estimates of heritability of weaning weight indicates more emphasis should be given to improve environmental conditions for better achievement.

Performance of steel beams strengthened with pultruded CFRP plate under various exposures

M. Gholami,A.R. Mohd Sam,A.K. Marsono,M.M. Tahir,I. Faridmehr 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.20 No.5

The use of Carbon Fiber Reinforced Polymer (CFRP) to strengthen steel structures has attracted the attention of researchers greatly. Previous studies demonstrated bonding of CFRP plates to the steel sections has been a successful method to increase the mechanical properties. However, the main limitation to popular use of steel/CFRP strengthening system is the concern on durability of bonding between steel and CFRP in various environmental conditions. The paper evaluates the performance of I-section steel beams strengthened with pultruded CFRP plate on the bottom flange after exposure to diverse conditions including natural tropical climate, wet/dry cycles, plain water, salt water and acidic solution. Four-point bending tests were performed at specific intervals and the mechanical properties were compared to the control beam. Besides, the ductility of the strengthened beams and distribution of shear stress in adhesive layer were investigated thoroughly. The study found the adhesive layer was the critical part and the performance of the system related directly to its behavior. The highest strength degradation was observed for the beams immersed in salt water around 18% after 8 months exposure. Besides, the ductility of all strengthened beams increased after exposure. A theoretical procedure was employed to model the degradation of epoxy adhesive.

Performance of partial strength connection connected by thick plate between column flanges

Tahir, Mahmood M.,Juki, Irwan,Ishak, Mohd Y.,Mohammad, Shahrin,Awang, Abdullah Z.,Plank, Roger Techno-Press 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.51 No.2

Traditional beam connections to the minor axis of a column have relatively low strength and stiffness. A modified detail, using a plate welded between the toes of the column flange - referred to as a toe plate connection - is examined in this paper. The results of an experimental investigation for both flush and extended end-plate connections connected to a 25 mm thick end-plate are presented. The tests are complemented by finite element modelling which compares very well with the test observations. The results show a significant increase in both moment resistance and initial stiffness for this connection detail compared with connections made directly to the column web. This offers the prospect of more optimal solutions taking advantage of partial strength frame design for the minor axis as well as major axis.

A Rapid Click Chemistry Using Beta-Cyclodextrin Immobilized on Glass Micro-Particles

Tahir, M.N.,Qamar, R.-u.,Mischnick, P.,Kim, J.,Jung, S. Bentham Science Publishers Ltd 2013 Letters in organic chemistry Vol.10 No.4

Effect of the Volatile Oil of Nigella sativa Seeds and Its Components on Body Temperature of Mice: Elucidation of the Mechanisms of Action

M. M. Ashour,K. E. H. El Tahir,M.G. Morsi,N.A. Aba-Alkhail 한국생약학회 2006 Natural Product Sciences Vol.12 No.1

effect(s) of the volatile oil (VO) of Nigella sativa and its two components, α-pinene and ρ-cymeneon body temperature of male and female conscious mice were studied. Further investigations to delineate themechanism(s) of action of the observed efect(s) by using various blockers involved in the central regulation ofbody temperature were made. VO and α-pinene caused significant reductions in rectal body temperature at is and30 minute after treatment. ρVO and α-pinene-induced hypothermia significantly. Nalbuphine inhibited α-pinene-induced hypothermiasignificantly but did not affect VO-induced hypothermia. Droperidol potentiated VO and α-pinene-inducedhypothermia to a non-significant level; whereas atropine potentiated VO-induced hypothermia non-significantly.The study confirms further the role of serotoninergic receptors in the mechanism(s) of the observedpharmacological efects of the VO of Nigella sativa. It also indicated a possible role of opioid receptors in α-KeywordsNigella sativa, α-pinene, ρ-cymene, receptor blockers, serotoninergic receptors

Soft robotics: A solid prospect for robotizing the natural organisms

Tahir, Ahmad M.,Naselli, Giovanna A.,Zoppi, Matteo Techno-Press 2018 Advances in robotics research Vol.2 No.1

Innovation is considered as key to ensure continuous advancement and firm progress in any field. Robotics, with no exception, has gained triumph and approval based on its strength to address divers range of applications as well as its capacity to adapt new ways and means to enhance its applicability. The core of novelty in robotics technology is the perpetual curiosity of human beings to imitate natural systems. This desire urges to continuously explore and find new feet. In the past, contemporary machines, in different shapes, sizes and capabilities, were developed that can perform variety of tasks. The major advantage of these developments was the ability to exhibit superior control, strength and repeatability than the corresponding systems they were replicating. However, these systems were rigid and composed of hard an underlying structure, which is a constraint in bringing into being the compliance that exists in natural organisms. Inspiration of achieving such compliance and to take the full advantage of the design scheme of biological systems compelled researchers and scientists to develop systems avoiding conventional rigid structures. This ambition, to produce biological duos, needs soft and more flexible materials and structures to realize innovative robotic systems. This new footpath to craft biological mockups facilitates further to exploit new materials, novel design methodologies and new control techniques. This paper presents an appraisal on such innovative comprehensions, conferring to their design specific importance. This demonstration is potentially useful to prompt the novelty of soft robotics.