Ammonium-perchlorate diffusion flames - A spectrographic investigation

Spectroscopic analyses on ammonium perchlorate diffusion flames with various fuel

Penerapan Strategi Pembelajaran Aktif Tipe Giving Question and Getting Answer (GQGA) untuk meningkatkan hasil belajar IPA Tema 6 Panas dan Perpindahannya kelas V SDN Nunbaun Sabu Kupang

Penelitian ini bertujuan untuk meningkatkan hasil belajar siswa dengan menerapkan Strategi Pembelajaran Aktif Tipe Giving Question and Getting Answer (GQGA) pada siswa kelas V SDN Nunbaun Sabu. Jenis penelitian yang digunakan adalah penelitian tindakan kelas (PTK) dengan 4 tahap yaitu perencanaan, pelaksanaan, observasi dan refleksi. Teknik analisis data yang digunakan melalui dua tahap yaitu teknik pengumpulan data dan teknik analisis data, indikator keberhasilan 75% dan nilai kriteria ketuntasan minimal (KKM) yaitu 75. Hasil penelitian ini menunjukkan bahwa hasil belajar siswa kelas V SDN Nunbaun Sabu setelah menerapkan Strategi Pembelajaran Aktif Tipe Giving Question and Getting Answer (GQGA) skor aktivitas guru siklus I mencapai 68,88. Dan siklus II mencapai 82,77 pada taraf sangat baik. Sedangkan hasil observasi aktivitas siswa  siklus I mencapai 60,11 dan siklus II mencapai 87,33. Adapun  nilai hasil belajar  siswa siklus I yang dimana siswa yang tuntas 12 anak dengan presentase 70,25 % dan siswa yang tidak tuntas 8 anak  dengan presentase ketidak tuntasan 40 %. Sedangkan nilai hasil belajar siswa pada siklus II dimana siswa yang tuntas ada 20 siswa dengan pencapaian 100 % dan tidak tuntas 0 %. Hal ini membuktikan bahwa . Penerapan Strategi Pembelajaran Aktif Tipe Giving Question and Getting Answer (GQGA) dapat meningkatkan hasil belajar siswa pada siswa kelas V SDN Nunbaun Sabu

An interconnected duplicated femoral vein and its clinical significance

Anatomical variations in the femoral vein are of great clinical importance especially in cases of deep vein thrombosis (DVT). Knowledge of the variable anatomy of the femoral vein is important to minimise false-negative findings on ultrasound examination in patients with DVT and help to explain the ‘silent’ DVT.Furthermore, the presence of a duplicated femoral vein itself is associated with higher incidence of DVT. These venous anomalies are usually due to the truncular venous malformation. In the present study, while dissecting the right lower limb, we found a case of variation of the femoral vein. In this case, besides a duplicated femoral vein, we also noticed a 3rd interconnecting channel near the apex of the femoral triangle joining the two veins. This variation has not been reported previously by other authors. Considering its uniqueness and clinical importance,we decided to report this case

Air Quality Study at Different Elevation Levels Using Drone Payload Air Quality Measurement Device (D-PAQ)

Construction sites can be found in both urban and rural areas, often in close proximity to residences. They can thus cause home pollution due to the distance and the materials used. This study aims to visualize PM2.5, PM10, temperature and humidity by producing air quality mapping and correlating parameters at the stadium and construction site. An Arduino-based air quality measurement payload device was developed to measure the air quality by different levels. The drone was used to collect air quality data by mounting the device to the drone. Measurements were taken at three different elevations for each study area, and the application software generates the air quality map based on the location coordinates. The correlation evaluation of the concentration of PM2.5 and PM10 with temperature and humidity was then determined. The results showed that the concentrations of PM2.5 and PM10 at the construction site are much higher compared to the stadium due to the construction activities nearby. Keywords: air quality, unmanned aerial vehicle, mappin

Combined effect of frustration and dimerization in ferrimagnetic chains and square lattice

Within the zero-temperature linear spin-wave theory we have investigated the effect of frustration and dimerization of a Heisenberg system with alternating spins $s_{1}$ and $s_{2}$ on one- and two-dimensional lattices. The combined effect most visibly appears in the elementary excitation spectra. In contrast to the ground state energy that decreases with dimerization and increases with frustration, the excitation energies are shown to be suppressed in energy by both dimerization and frustration. The threshold value of frustration that signals a transition from a classical ferrimagnetic state to a spiral state, decreases with dimerization, showing that dimerization further helps in the phase transition. The correlation length and sublattice magnetization decrease with both dimerization and frustration indicating the destruction of the long-range classical ferrimagnetic. The linear spin wave theory shows that in the case of a square lattice, dimerization initially opposes the frustration-led transition to a spiral magnetic state, but then higher magnitudes of lattice deformation facilitate the transition. It also shows that the transition to spiral state is inhibited in a square lattice beyond a certain value of dimerization.Comment: 8 pages, latex, 12 postscript figure

ТЕМПЕРАТУРНОЕ ПОЛЕ ВЫХЛОПНЫХ ГАЗОВ АВТОМОБИЛЕЙ И РАСЧЁТЫ СТАТИСТИЧЕСКИХ СВЕДЕНИЙ

There are too many problems from the gases which constantly fly out from the exhaust pipes of cars and lorries, especially if this process takes place in the closed apartment (garage, laboratory, class, station of diagnostic or repair for transport systems with diesel or petrol engine). Practically all gases poison air, bring essentially injury to the health of people and for the all nature. Hitherto, many scientists affirm that gases create the negative hotbed effect in the atmosphere and influence to the appearance of the ozone holes. Some important experiments and investigations at the present day didn’t make.In this article there are several technical decisions not only how to decrease the negative influence of gases but the special calculations using personal computer and statistical information to describe the process by a chart.  Существует много проблем с газами, которые вылетают постоянно из выхлопных труб легковых автомобилей и грузовиков, особенно если имеет место этот процесс в закрытых помещениях (гараж, лаборатория, класс, станция диагностики или ремонта транспортных систем с дизельным или бензиновым двигателем). Практически все газы отравляют воздух, приносят существенный вред здоровью людей и всей природе. Поэтому многие учёные утверждают, что газы создают негативный парниковый эффект в атмосфере и влияют на появление озоновых дыр. Некоторые важные эксперименты и исследования в настоящее время сделаны.В этой статье есть несколько технических решений не только как уменьшить негативное влияние газов, но и специальные расчёты, используя персональный компьютер и статистическую информацию, чтобы описать процесс графически.

Perinatal and infant outcome in prenatally diagnosed hyperechogenic kidneys

Objective: Hyperechogenic kidneys are a relatively rare antenatal finding, which can generate significant parental anxiety due to uncertain prognosis. We report on the perinatal and infant outcomes of a large cohort of fetuses with antenatally diagnosed hyperechogenic kidneys. Methods: This was a retrospective analysis of all cases diagnosed prenatally with hyperechogenic kidneys between 2002 and 2017 in a large tertiary fetal medicine unit. Hyperechogenicity was defined as kidney parenchyma with greater echogenicity than that of the liver. Pregnancy, pathological and postnatal outcomes were collected from hospital and general practitioner records up to 1 year of age. Abnormal renal outcome was defined as elevated creatinine beyond 6 months of age, hypertension requiring medication or major kidney surgery, such as nephrectomy. Severe abnormal renal outcome was defined as the need for dialysis or kidney transplant at any stage. Results: Three-hundred and sixteen fetuses with hyperechogenic kidneys were identified at a mean gestational age of 21 (range, 13–37) weeks. The majority of cases (97%) had bilateral hyperechogenic kidneys. In the 265 cases with available follow-up data, other associated renal tract abnormalities were identified prenatally in 36%, concomitant extrarenal structural abnormalities in 39% and abnormal karyotype in 15% of cases. Of the 316 included cases, 139 did not survive, including 105 terminations of pregnancy, five intrauterine deaths and 29 early neonatal deaths. Only 4.3% (6/139) of these fetuses had isolated hyperechogenic kidneys while 28.1% (39/139) had associated multiple renal tract abnormalities alongside hyperechogenic kidneys and over two-thirds (67.6%; 94/139) had concomitant extrarenal abnormalities. Of the 177 cases that survived beyond 1 month of age, outcome data were available in 126. Of these, based on the antenatal findings, 60 (47.6%) cases had isolated hyperechogenic kidneys, 56 (44.4%) had associated renal structural abnormalities and 10 (7.9%) had additional extrarenal abnormalities. Considering renal outcome alone, kidney function was abnormal in 13 (21.7%), 10 (17.9%) and 0 (0%) infants in these three groups, respectively, although concurrent pathology clearly affected global outcome in the more complex cases. Neonatal mortality of 1.6% was observed in the isolated renal hyperechogenicity group. The presence of oligohydramnios or abnormal renal volume was not associated significantly with abnormal renal function (odds ratio (OR), 2.32 (99% CI, 0.54–10.02) and OR, 0.74 (99% CI, 0.21–2.59), respectively) in this group. Conclusions: Hyperechogenic kidneys are often complicated by associated renal tract and extrarenal abnormalities, aberrant karyotype and genetic disease, and these factors have a greater effect on overall outcome than does kidney echogenicity. The renal outcome of fetuses with isolated hyperechogenic kidneys is good generally, with over 70% of cases having normal renal function postpartum. Importantly, for prognostic counseling, all of the fetuses in this non-selected series with isolated hyperechogenic kidneys and normal amniotic fluid levels had normal renal outcome in infancy. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology

Friction characteristic study on flat surface embedded with micro pit

Mechanical systems are always deal with wear and friction as the liability. The basic principle of the mechanical system is the surface interaction between surfaces which have a frictional force resulting in fatigue and damage to the mechanical components. Lubricant is used to minimize friction in order to solve the problem. A comparative friction characteristic analysis was then conducted to assess the coefficient of friction (COF) between Aluminum Alloy 5083 block and SKD 11 disk using two types of lubricant, that is SAE40 engine oil and RBD palm oil. The thickness of the oil film could be predicted in order to observe the influence of the different lubricants used. Pit pattern surface is required to research the function of the pit as a lubricant reservoir. The experiment was carried out in the laboratory according to the ASTM G99. Load is applied to experiments with loads of 1 kg, 5 kg and 10 kg, in order to find a COF correlation under different application condition. The rotational speed is held constant at 3m/s during the experiment. The results obtained revealed that when using RBD palm oil as a lubricant, the COF between block and disk is lower than when using SAE40 engine oil as a lubricant. The experimental result showed that RBD palm oil can minimize friction much lower than SAE40 engine oil. Based on the results of the comparison analysis on the flat surface and pit pattern surface, the finding revealed that the pit pattern may serve as a lubricant reservoir to retain and store the lubricant for longer than the flat surface that helps to reduce friction

The effectiveness of jet impingement cooling system on various flat plate surface

This manuscript present investigation the effectiveness of jet impingement cooling system on flat plate surface. Jet impingement can give high heat flux cooling effect. This type of cooling system is very useful as it may be used in a lot of machine and instruments such as piston, supercomputer, microchip, food technology and hybrid car electronic circuit. This project have three main objectives that need to achieve. Firstly, this project can determine the best distance from nozzle to plate surface and then determine the dimensionless ratio between distance from nozzle to plate surface and the diameter of circular nozzle. Next is this project can observe the best mass blow rate, ranging from laminar flow to turbulent flow. The purpose to having two types of flows is to check which flow can give the best cooling effect. Lastly, by choosing three type of materials that have different surface roughness is to study the effect of surface roughness and cooling effect. From the experiment, higher surface roughness does not give the best cooling effect while smoother surface roughness give the better results. However, just like mass blow rate, it has it range on where the best cooling effect can be achieved. If the difference between surface temperature and isothermal temperature is too high, it will be a drawback to the cooling system. For the final result, the best jet impingement cooling system can be obtained at dimensionless s/d = 10 at mass blow rate equal to 8.4 m/s using zinc plate

Properties of wood polymer nanocomposites impregnated with ST-co-EDA/nanoclay

Study has been made on manufactured wood polymer nanocomposites (WPNC) from Sesendok wood through impregnation of Styrene (ST), Ethyldimethylamine (EDA) and Montmorillonite (MMT) nanoclay. The impregnation process of the wood samples by vacuum-pressure method with in-situ polymerization of prepolymer mixture was used. The wood samples structural properties were investigated with Dynamic Mechanical Thermal Analysis (DMTA), Fourier Transform Infrared (FTIR), X-ray Diffraction (XRD) analysis and Scanning Electron Microscopy (SEM) found to be extensively changed upon ST-co-EDA/MMT impregnated. The mechanical properties of the WPNC samples were significantly increased by ST-co-EDA/MMT treatment. Thermal properties of WPNC samples were also evaluated using themogravimetric analysis (TGA) and an improvement in thermal stability was found for WPNC. WPNC has shown excellent resistance against weathering effect while exposed to surrounding. WPNC can be used to replace plastic and synthetice materials for its excellent properties and high market demand of the modern society