Pengaruh Penambahan Accelerator “Kcl”, “Na2sio3”, Dan “Calseal” Sebagai Additive Semen Kelas a Terhadap Thickening TIME, Compressive Strength, Dan Rheology Bubur Semen Dengan Variasi Temperatur (Bhct) Di Laboratorium Pemboran Dan Produksi Universitas Trisakti

Salah satu problem yang terjadi pada perencanaan kegiatan penyemenan adalah penentuanformulasi bubur semen yang diharapkan sesuai dengan kondisi sumur yang menjadi targetpenyemenan. Bubur semen terlebih dahulu dirancang sedemikian rupa dan diuji kelayakannyasebelum digunakan untuk penyemenan, sehingga sesuai dengan karakteristik sumur targetpenyemenan. Berbagai additive digunakan untuk memaksimalkan formulasi bubur semen yangdisesuaikan dengan karakteristik sumur yang akan disemen.Penelitian ini dilakukan untukmengetahui pengaruh penambahan konsentrasi accelerator “KCl”, “Na2SiO3”, dan “Cal-Seal”Sebagai Additive Semen Kelas A Terhadap Thickening Time , Compressive Strength, danRheologi Bubur Semen Dengan Variasi Temperatur (BHCT)”. Temperatur yang digunakan adalah60°C, 70°C, dan 80°C, dengan variasi konsentrasi accelerator 0,5 %, 1,0 %, 1,5 % dan 2,0 %.Penelitian ini dilakukan sesuai standar kelayakan API 10A (specification for cement and materialsfor well cementing)

Perbandingan Hasil Belajar Fisika dengan Menggunakan Laboratorium Nyata dan Laboratorium Virtual

This research aims to know compare the results of the student in X MAN Darussalam which taught by real lab and virtual lab at Newton's Law matter. The sampling in this research were taken by using purposive sampling technique that was selected the student on X-IPA totally 20 students as the class experimental 1 and the student on X-IPA2 totally 25 students as the class experimental 2. The data obtained from tests of student learning outcomes are taught by real laboratory and virtual laboratories and data analysis techniques used by formula “uji-t”. Obtained results of data analysis based on the criterion of testing the two parties received H0 if –t(1 - 1/2 α) - ttabel and t -2.021 and 1.76 < 2.021 then declared Ho received. Based on the data analysis revealed the research hypothesis is rejected. It can be concluded that there isn't differences in physics learning outcomes are taught by real laboratory and virtual laboratories in X MAN Darussalam on Newton's laws of matter

Penerapan Model Pembelajaran Generatif Berbantu Simulasi Physics Education Technology (Phet) untuk Meningkatkan Hasil Belajar Siswa

The research aimed to find out the results of student learning, teacher and student activities, teachers 'skills in managing learning, and students' response to the use of Generative Learning Model simulations PhET assisted in the learning process. The approach used in this study is a quantitative approach in the form of classroom action research (PTK). The research data was sourced from the students of class XI-MIA 3 SMAN 12 Banda Aceh the school year 2015/2016 totaling 29 students, 9 male students and 20 female students. Data collection instruments used in this study is the observation sheets, sheets of test in the form of pre-test and post-test at the beginning of the end of learning, and student feedback questionnaire sheets were analyzed using analysis of all three percentages. The result showed that (1) An increase in the activities of teachers and students during the learning process in each cycle, (2) There was an increase in the skills of teachers in managing learning in each cycle of the medium category to be very good, (3) The percentage of classical completeness overall well increase of 62%, 72% and 93%, and (4) the students tend to be positive where 86% of students said he was happy to learning by using model-assisted simulation generative this PhET. Based on data obtained from this study can be concluded that the application of the generative learning model-assisted simulation PhET on the material elasticity and Hooke's Law can improve learning outcomes of students of class XI-MIA 3 at SMAN 12 Banda Aceh in terms of both individual and classical completeness completeness

Low Noise, High Gain RF Front End Receiver at 5.8GHz for WiMAX Application

This paper presents the design of a high gain, low noise direct conversion Radio frequency(RF) front-end receiver system. The Front end receiver is designed to operate at 5.8 GHz in compliant with IEEE 802.16 WiMAX standard. The system consists of a low noise amplifier (LNA), a radio frequency amplifier (RFA), a power divider and two band pass filters. The design process involved the use of software such as ADS 2000A, Ansoft Designer and MathCad. FET FHX76 LP is used in the design of the LNA due to its low noise figure and high impedance input. As for the RFA design,FET EPA018A was used. The LNA and the RFA used T lumped reactive element network and microstrip line matching network. Two 3 dBπ -attenuators were inserted at the input and output of the RFA to isolate the system from the reflected load power. A Wilkinson power divider is developed for two equal power structures using impedance microstrip line technique. Microstrip technology was used for designing the Chebyshev filter. The result of each module for the front end is presented

The relationship between water quality and black fly (Diptera: Simuliidae) abundance in Tambunan District, Sabah

Black flies (Diptera : Simuliidae) have been extensively studied almost worldwide (Hamada & Grillet, 2001). This is because blackflies are among the best-known aquatic insects and globally distributed (Adler et al., 2004). Black flies in Malaysia are less known and research about this aquatic insect is still scarce especially in Borneo region. Most of the earlier studies on black flies in Sabah were related to taxonomy (Takaoka, 2001). However, studies on ecology and the role of black flies as bio-indicator has so far not been well reported yet. The aim of this study is to determine the relationship of water quality against the abundance of black flies pupa (Simuliidae). Regression test shows that relationship between dissolve oxygen (r2=0.57, p=0.02), total dissolve substance (TDS) (r2=0.18,p=0.04) and conductivity (r2=0.14, p=0.04) appeared significant to the abundance of black flies pupae. All the study sites (6 rivers) were classified into Class 1 based on Water Quality Index Classification (DOE, 2006)

Karakteristik Partikel Arang Kayu Kelengkeng Hasil Tumbukan Mesin High Energy Ball Milling (HEBM) dan Pemanasan Lanjut

Nanoparticles become a very interesting study, because nanoparticles exhibit true properties–completely new or better based on specific characteristics (morphological size, phase, etc.). In this study conducted the study of nanoparticles of wood charcoal curvature which in production with a top-down approach using collision method with model Shaker Mills. Characteristics of particles with PSA test, SEM test and EDX test to analyse the size of carbon particles, surface morphology and chemical composition contained in the material of collision results. From the PSA test results, at 2.5 million the collision cycles were obtained the smallest size of 0.453 μm and the volume 0.001%, the average size was 15.157 μm and the volume was 7.550%, the largest size was 434.912 μm and the volume was 0.001%. From the SEM test results in the cycle of 2.5 million cycles resulted in the size of the Carbonya particle is small and many. The EDX element test results that result in carbon particle size, C = 95.58%. Potassium oxide, K2O = 0.75%. KalsiumOksida, CaO = 1.76%. Copper (II) oxide, CuO = 0.44%. Zink oxide, ZnO = 0.44%. Zirkronium dioxide, ZrO2 = 0.86%

The Effect of Mesoporous H-ZSM-5 Crystallinity as a CaO Support on the Transesterification of Used Cooking Oil

Transesterification of used cooking oil was carried out over calcium oxide supported on mesoporous H-ZSM-5 prepared from kaolin as solid base catalysts. Solid basic catalysts investigated in this study were characterized by XRD, FTIR spectroscopy, and N2 adsorption-desorption techniques. The XRD pattern showed peaks corresponding to the CaO and mesoporous ZSM-5 in the sample. The peak intensity of the CaO increased as CaO loading in ZSM-5 was increased. The characterization based on FTIR spectroscopy revealed that CaO/H-ZSM-5 solids have functional groups characteristics of both CaO and mesoporous H-ZSM-5 which appeared in the band at around  550 cm-1 and 480 cm-1. The isotherm of N2 adsorption-desorption of CaO/H-ZSM-5 indicated the type IV isotherm with the presence of hysteresis loop. For the catalytic activity, the biodiesel yield using catalyst of 10 % CaO/HZSM-5 (100 %), 30 % CaO/HZSM-5 (100 %), 50 % CaO/HZSM-5 (100 %) were 24.34, 27.37, and 29.73 %, respectively. It also related with the basic active site, when loading CaO increased, the basic active site also increased.

Experimental investigation of air-conditioning electrical compressor using binary TiO2–SiO2 polyol-ester nanolubricants

As electric vehicles (EVs) continue to replace conventional gasoline vehicles, maintaining thermal comfort within the car requires additional energy to operate the automotive air-conditioning (AAC) system. This work aims to optimise the electrically driven compressor (EDC) system utilising polyol-ester (POE)-based binary nanolubricants to enhance performance and minimise the size of the EV battery and AAC components. A binary nanolubricant was formulated using a two-step method of formulation. The TiO2–SiO2/POE binary nanolubricant was prepared at different volume concentrations ranging from 0.01 to 0.1 %. The experiment was conducted for the 1200–3840 rpm compressor speed with different initial refrigerant charges between 120 and 160 g. The heat absorption rose by up to 44.2 % while utilising the binary nanolubricant at a volume concentration of 0.03 %. The coefficient of performance (COP) reached its maximum value of 2.43 at a refrigerant charge of 160 g and compressor speed of 1860 rpm. Furthermore, the binary nanolubricant significantly reduced the expansion valve discharge temperature, exhibiting a substantial decrease of up to 51.6 %. The highest COP increment, up to 23.4 %, was achieved at a volume concentration of 0.03 %. Hence, it is recommended to utilise 0.03 % TiO2–SiO2/POE binary nanolubricant to achieve optimal performance in the AAC-EDC system

Bose-Einstein correlations for Levy stable source distributions

The peak of the two-particle Bose-Einstein correlation functions has a very interesting structure. It is often believed to have a multivariate Gaussian form. We show here that for the class of stable distributions, characterized by the index of stability $0 < \alpha \le 2$, the peak has a stretched exponential shape. The Gaussian form corresponds then to the special case of $\alpha = 2$. We give examples for the Bose-Einstein correlation functions for univariate as well as multivariate stable distributions, and check the model against two-particle correlation data.Comment: 30 pages, 1 figure, an important misprint in former eqs. (37-38) and other minor misprints are corrected, citations update

NMR as a “gold standard” method in drug design and discovery

Studying disease models at the molecular level is vital for drug development in order to improve treatment and prevent a wide range of human pathologies. Microbial infections are still a major challenge because pathogens rapidly and continually evolve developing drug resistance. Cancer cells also change genetically, and current therapeutic techniques may be (or may become) ineffective in many cases. The pathology of many neurological diseases remains an enigma, and the exact etiology and underlying mechanisms are still largely unknown. Viral infections spread and develop much more quickly than does the corresponding research needed to prevent and combat these infections; the present and most relevant outbreak of SARS-CoV-2, which originated in Wuhan, China, illustrates the critical and immediate need to improve drug design and development techniques. Modern day drug discovery is a time-consuming, expensive process. Each new drug takes in excess of 10 years to develop and costs on average more than a billion US dollars. This demonstrates the need of a complete redesign or novel strategies. Nuclear Magnetic Resonance (NMR) has played a critical role in drug discovery ever since its introduction several decades ago. In just three decades, NMR has become a “gold standard” platform technology in medical and pharmacology studies. In this review, we present the major applications of NMR spectroscopy in medical drug discovery and development. The basic concepts, theories, and applications of the most commonly used NMR techniques are presented. We also summarize the advantages and limitations of the primary NMR methods in drug development