Maximising utility savings through appropriate implementation of combined heat and power scheme

Combined Heat And Power (CHP) Scheme, Also Known As Cogeneration Is Widely Accepted As A Highly Efficient Energy Saving Measure, Particularly In Medium To Large Scale Chemical Process Plants. The Advantages Of A CHP Scheme For A Chemical Plant Are Two-Fold: (I) To Drastically Reduce Electricity Bill From On-Site Power Generation (Ii) To Save On Fuel Bills Through Recovery Of The Quality Waste Heat From Power Generation For Process Heating. In Order To Be Effective, A CHP Scheme Must Be Placed At The Right Temperature Level, In The Context Of An Overall Process System. Failure To Do So Might Render A CHP Venture Worthless. This Paper Describes The Procedure For An Effective Implementation Of A CHP Scheme Using An Ethyl Benzene Process As A Case Study. A Key Visualisation Tool In Pinch Analysis Technique Known As The Grand Composite Curve Is Used To Guide CHP Integration, And Allows It To Be Optimally Placed Within The Overall Process Scenario. The Study Shows That Appropriate CHP Integration With The Ethyl Benzene Process Above The Pinch Can Potentially Result In Significant Savings On Electricity Cost Of Up To 87%

Electrically driven magnetization of diluted magnetic semiconductors actuated by Overhauser effect

It is well-known that the Curie temperature, and hence the magnetization, in diluted magnetic semiconductor (DMS) like Ga$_{1-x}$Mn$_x$As can be controlled by changing the equilibrium density of holes in the material. Here, we propose that even with a constant hole density, large changes in the magnetization can be obtained with a relatively small imbalance in the quasi-Fermi levels for up-spin and down-spin electrons. We show, by coupling mean field theory of diluted magnetic semiconductor ferromagnetism with master equations governing the Mn spin-dynamics, that a mere splitting of the up-spin and down-spin quasi-Fermi levels by 0.1 meV will produce the effect of an external magnetic field as large as 1 T as long as the alternative relaxation paths for Mn spins (i.e. spin-lattice relaxation) can be neglected. The physics is similar to the classic Overhauser effect, also called the dynamic nuclear polarization, with the Mn impurities playing the role of the nucleus. We propose that a lateral spin-valve structure in anti-parallel configuration with a DMS as the channel can be used to demonstrate this effect as quasi-Fermi level splitting of such magnitude, inside the channel of similar systems, have already been experimentally demonstrated to produce polarization of paramagnetic impurity spins.Comment: Title, abstract and the body of the paper was modified although the basic conclusions remain unchanged. The modified version contains 7 pages, 4 figures

An Interacting Scenario for Dark Energy in Bianchi Type-I Universe

We study the interaction between dark energy (DE) and dark matter (DM) in the scope of anisotropic bianchi type I space-time. First we derive the general form of the dark energy equation of state parameter (EoS) in both non-interacting and interacting cases and then we examine it's future by applying a hyperbolic scale factor. It is shown that in non-interacting case, depending on the value of the anisotropy parameter $K$, the dark energy EoS parameter is varying from phantom to quintessence whereas in interacting case EoS parameter vary in quintessence region. However, in both cases the dark energy EoS parameter $\omega^{de}$, ultimately (i. e at $z=-1$) tends to the cosmological constant ($\omega^{de}=-1$). Moreover, we fixed the cosmological bound on the anisotropy parameter $K$ by using the recent observational data of Hubble parameter.Comment: 12 pages, 6 figures, Research in Astronomy and Astrophysics, 201

Peningkatan Aktivitas Peserta Didik dalam Pembelajaran IPA Menggunakan Metode Inkuiri di Kelas IV Sdn

The purpose of this study is to describe the increase in the activity of learners in the learning of Natural Sciences using inquiry methods. This study used a descriptive method of research is the form of action research. This research was conducted for 3 cycles. The results of this study are as follows: baseline physical activity indicator by 24.64% to 97.10% the third cycle. There is a difference of 72.46%. Thus the increase in physical activity can be categorized as "High". Baseline on indicators of mental activity by 21.01% to 96.36% the third cycle. There is a difference of 75.35%. Thus the increase in mental activity can be categorized as "High". Baseline on indicators of emotional activity of 23.92% to 97.83% .Terdapat third cycle difference of 73.91%. Thus the increase in emotional activity can be categorized as "High"

Peningkatan Aktivitas Belajar Siswa dengan Media Nyata Kelas 1 Sdn 08 Kuala Mandor B

: Increase Student Learning Activities With Tangible MediaClass 1 SDN 08 Kuala Foreman B. This research aims to enhancestudents learning activities using real media class 1 SDN 08 KualaForeman B. Research method used is the method deskri. This studydesign included studies introduction, planning,action, observation andreflection. As for the preliminary studies carried out to obtain thereflectionawal. Subsequent remedial measures done in theclassicallearning as much as 2 cycle. Based on the observation made by twocycles with three times the meeting, the Grade 1 students learningactivities SDN 08 Kuala Foreman B having increased to 55,45% from68,20% in cycle I first meeting, 87,26% in cycle I meeting second.Then excellent increase of 100% in cycle II

Peningkatan Hasil Belajar Peserta Didik pada Pembelajaran Matematika dengan Metode Demonstrasi Kelas IV SD

, The purpose of this research in to repair the students' lesson result by using demonstration method in math for fourth grade students of SDN 01 Belitang. This Method is qualitative an classroom action research (CAR). The subject of this research is the fourth grade students of SDN 01 Belitang, which is contain of 21 boys and 17 girls. For the lesson plan in the first cycle the average score is 61,45 (enaugh), and in the second cycles, the average score is 76,58 (good). In the implementation first cycle average score 2,80 (enaugh) and in the second cycle average score is 3,00 (good). The result of the first cycle, average score is 61,45 ( enaugh) an the second cycle, the average score is 76,58 (good)

Meningkatkan Aktivitas dengan Metode Kerja Kelompok Pembelajaran IPA Kelas IV Sdn 17 Sungai Ambawang

. Students appear are not active in the teaching and learning process. One appropriate solution to overcome this problem is by applying the method of group work in science learning. The reseacrh method used descripfted method. The research type classrom action research.After the use of the method of group work in teaching and learning process about the science of matter from liquid obtained percentages of student learning activities amounted to 84.53% in the first cycle and the second cycle 92.22%. The student s responses to the use of the method of group work in science learning in 4th grade SDN 17 Sungai Ambawang Kubu Raya regency is very positive, reaching 87.6%. From these results show that the use of method of group work is appropriate to increase the activity 4th grade students of SDN 17 Sungai Ambawang Kubu Raya regency