Magnetotail structures in a simulated Earth's magnetosphere

The structure of the magnetotail is investigated in a laboratory simulated magnetosphere. Particular emphasis is placed on the region of distant magnetotail where the closed field line region of the plasma sheet terminates and the process of reconnection takes place. Our study builds upon the previous investigation of the magnetotail where the main results were based on the magnetic field measurements in the tail region of the simulated magnetosphere. In this paper, more elaborate measurements of plasma flow and electric field are presented. Besides these measurements, this region of distant magnetotail is also explored by high resolution imaging with a gated optical imager (GOI) and by digital image analysis. These images clearly reveal a Y-type magnetic neutral line for the northward 'interplanetary' field (IMF) and a usual X-type for the southward IMF that confirms our previous results deduced from the magnetic field measurements. In the neighborhood of these neutral points a strong component of dawn to dusk electric field (E(sub y)) and a counterstreaming plasma flow is also observed. Plasma flow is measured by using a double sided Faraday cup which is also used to measure the y-component of tail current (J(sub y)) at different locations. These measurements reveal that the tail current is not carried by ions as previously thought, rather it is carried by electrons alone

High yield fusion in a Staged Z-pinch

We simulate fusion in a Z-pinch; where the load is a xenon-plasma liner imploding onto a deuterium-tritium plasma target and the driver is a 2 MJ, 17 MA, 95 ns risetime pulser. The implosion system is modeled using the dynamic, 2-1/2 D, radiation-MHD code, MACH2. During implosion a shock forms in the Xe liner, transporting current and energy radially inward. After collision with the DT, a secondary shock forms pre-heating the DT to several hundred eV. Adiabatic compression leads subsequently to a fusion burn, as the target is surrounded by a flux-compressed, intense, azimuthal-magnetic field. The intense-magnetic field confines fusion $\alpha$-particles, providing an additional source of ion heating that leads to target ignition. The target remains stable up to the time of ignition. Predictions are for a neutron yield of $3.0\times 10^{19}$ and a thermonuclear energy of 84 MJ, that is, 42 times greater than the initial, capacitor-stored energy

MODELING AND ANALYSIS OF MAGNETIZED CHEMICALLY REACTIVE FLUID FLOW PAST OVER POROUS STRETCHED SHEET

The aim of this article to inspect the effect of nonlinear thermal radiation, heat joule, viscous dissipation and magnetic field on viscoelastic second grade fluid. Flow is generated due to stretching of sheet. Flow features are studied considering hydrodynamic boundary conditions. Chemical reaction on the surface is further accounted. The flow governing nonlinear partial system of differential equations is obtained incorporating boundary layer assumptions. The dimensional model is made dimensionless by taking suitable transformations and then tackled via HAM for convergent series solution. Effects of flow controlling parameters on velocity, concentration, temperature, local skin friction coefficient, Sherwood number and Nusselt numbers are discussed by plotting graphs. Main observations are listed at the end

Chemical and biological investigations of Delonix regia (Bojer ex Hook.) Raf.

U radu je opisana izolacija pet sastojaka petroleterske i diklormetanske frakcije metanolnog ekstrakta kore biljke Delonix regia: lupeol (1), epilupeol (2), β-sitosterol (3), stigmasterol (4) i p-metoksibenzaldehid (5). Nadalje, testirano je antimikrobno djelovanje različitih ekstrakata difuzijskom metodom na disku (15 μg mm2). Zone inhibicije za sastojke topljive u petroleteru, tetraklormetanu i diklormetanu bile su 914 mm, 1113 mm, odnosno 920 mm, dok je zona inhibicije standarda kanamicina bila 2025 mm. U biološkom pokusu smrtnosti morskih kozica najveću toksičnost pokazali su spojevi topljivi u tetraklormetanu (LC50 = 0,83 μg mL1), dok je topljivost sastojaka topljivih u petroleteru i diklormetanu bila LC50 14,94, odnosno 3,29 μg mL1, a standarda vinkristin sulfata 0,812 μg mL1. Ovo je prvo izvješće o izolaciji sastojaka, antimikrobnom djelovanju i citotoksičnosti biljke D. regia.In this study five compounds, lupeol (1), epilupeol (2), β-sitosterol (3), stigmasterol (4) and p-methoxybenzaldehyde (5) were isolated from the petroleum ether and dichloromethane fractions of a methanolic extract of the stem bark of Delonix regia. Antimicrobial screening of the different extracts (15 μg mm2) was conducted by disc diffusion method. The zones of inhibition demonstrated by the petroleum ether, carbon tetrachloride and dichloromethane fractions ranged from 914 mm, 1113 mm and 920 mm, respectively, compared to kanamycin standard with the zone of inhibition of 2025 mm. In brine shrimp lethality bioassay, the carbon tetrachloride soluble materials demonstrated the highest toxicity with LC50 of 0.83 μg mL1, while petroleum ether and dichloromethane soluble partitionates of the methanolic extract revealed LC50 of 14.94 and 3.29 μg mL1, respectively, in comparison with standard vincristine sulphate with LC50 of 0.812 μg mL1. This is the first report on compounds separation from D. regia, their antimicrobial activity and cytotoxicity

Faktor-faktor Yang Berhubungan Dengan Perilaku Makan Pada Remaja SMA Negeri 1 Palu

Perilaku makan adalah suatu keadaan yang menggambarkan perilaku seseorang terhadap tata krama makan, frekuensi makan, pola makan, kesukaan makan, dan pemilihan makanan. Konsumsi zat gizi yang tidak optimal berkaitan dengan kesehatan yang buruk. Bila konsumsi zat gizi selalu kurang dari kecukupan maka seseorang akan mengalami gizi kurang, sebaliknya jika konsumsi melebihi kecukupan akan menderita gizi lebih dan obesitas. Konsumsi zat gizi yang seimbang dan sesuai dengan kebutuhan akan membantu remaja mencapai pertumbuhan dan perkembangan yang optimal. Faktor-faktor yang mempengaruhi perilaku makan terbagi atas faktor eksternal dan internal. Penelitian ini bertujuan untuk mengetahui “Faktor-faktor yang berhubungan dengan perilaku makan pada remaja SMA Negeri 1 Palu”. Jenis penelitian survei analitik dengan pendekatan Cross Sectional Study. Populasi berjumlah 921 orang dan jumlah responden sebanyak 91 orang, menggunakan teknik proportional random sampling. Data penelitian ini diuji secara statistik dengan uji Chi-square. Hasil penelitian menunjukkan bahwa ada hubungan antara pendapatan orang tua (ρ= 0,004) dan pengetahuan gizi (ρ = 0,000) dengan perilaku makan. Dengan pendapatan yang diperoleh, keluarga dapat mengonsumsi makanan bergizi seimbang seperti tahu, tempe, ikan, sayur-sayuran yang harganya relatif terjangkau. Melalui pengetahuan gizi, responden menjadi tahu bahwa kesehatan berhubungan erat dengan makanan yang dikonsumsi sehari-hari. Dalam penelitian ini ditemukan pula tidak ada hubungan antara teman sebaya (ρ= 1,000) dengan perilaku makan. Mayoritas responden masih tinggal bersama orang tua sehingga orang tua masih memegang peranan penting dalam membentuk perilaku makan anak

Analisis Penentuan Jenis Fluida Pendorong Menggunakan Metode Material Balance Berdasarkan Nilai Recovery Factor Pada Lapangan “Arl” Petrochina International Jabung Ltd

Lapangan “ARL” telah berproduksi sejak bulan Januari 2001. Diketahui bahwa mekanisme pendorong yang bekerjapada reservoir ini merupakan water drive. Untuk meyakinkan hasil tersebut, maka dilakukan pengkajian ulang denganmenggunakan metode yang berbeda sebagai bahan validasi. Berdasarkan analisa mekanisme pendorong yang telahdilakukan dengan menggunakan metode material balance, reservoir lapangan ini benar memiliki jenis Water DriveMechanism sebagai mekanisme pendorongnya dimana tenaga pendorong terbesarnya didominasi oleh air, yaitu WaterDrive Index (WDI) 74,1%, Untuk meyakinkan hasil analisis dengan menggunakan metode material balance tersebut,maka dilanjutkan dengan perhitungan recovery factor dengan metode decline curve.Nilai recovery factor yang didapat dari hasil perhitungan ini adalah 37,58% dengan prediksi kumulatif minyak sampaiSeptember 2013 ini adalah sebesar 21.432 MBBL dan Remaining Reserve (RR) sebesar 11.357 MBBL, makaLapangan “ARL” ini masih menyisakan cadangan (EUR) sebesar 32.789 MBBL.yang secara teori membenarkanbahwa tingkat perolehan berkisar 35-75% merupakan kisaran efisiensi perolehan minyak pada jenis water drivereservoir

Composition and structure of plant communities in the Moist Temperate Forest Ecosystem of the Hindukush Mountains, Pakistan

Peer reviewedPublisher PD

Compact relativistic geometries in f(R,G)f(R,G) gravity

One of the possible potential candidates for describing the universe's rapid expansion is modified gravity. In the framework of the modified theory of gravity $f(R,G)$, the present work features the materialization of anisotropic matter, such as compact stars. Specifically, to learn more about the physical behavior of compact stars, the radial, and tangential pressures as well as the energy density of six stars namely $Her X-1$, $SAXJ1808.4-3658$, $4U1820-30$, $PSR J 1614 2230$, $VELA X-1$, and $Cen X-3$ are calculated. Herein, the modified theory of gravity $f(R,G)$ is disintegrated into two parts i.e. the $\tanh$ hyperbolic $f(R)$ model and the three different $f(G)$ model. The study focuses on graphical analysis of compact stars wherein the stability aspects, energy conditions, and anisotropic measurements are mainly addressed. Our calculation revealed that, for the positive value of parameter n of the model $f(G)$, all the six stars behave normally.Comment: Some changes have been made. " To appear in International Journal of Geometric Methods in Modern Physics

Stability-Centric Design of a Droop-Mounted Adaptive Nonlinear Control for EV Charging in DC Microgrid

This paper presents a streamlined two-layer control system for effective power sharing and switching control in a DC microgrid designed for electric vehicles. The system integrates Energy Storage Systems and advanced converters to ensure a broad operational range and bidirectional power flow. The Dual active bridge topology is used to integrate the EV to DC MG. Hence, the DC MG system has multiple power converter operating simultaneously. The enhanced droop control strategy is advised for the upper layer and the switching controller is derived using nonlinear controls theory embedding the barrier functions. The enhanced droop strategy shares the power considering the individual dynamics of the storage devices while Barrier-based sliding mode control is applied to converters for current/voltage tracking. Mathematical analysis, leveraging Lyapunov's theory, confirms the large signal stability of the system. Demonstrated through MATLAB/Simulink-based simulations, the control system exhibits proficient load power sharing, and the adaptive nonlinear controller showcases robustness against unforeseen disturbances. Moreover, the comparative analysis provides insight into the performance of the proposed control methods concerning traditional methods. Hardware-in-loop tests, utilizing Typhoon HIL 404, authentically validate the real-time performance of the proposed control strategies. Different EV and Constant Power Load scenarios ensure a thorough examination, supporting the efficacy of the system. The study contributes valuable insights into the feasibility and efficiency of these control strategies, paving the way for advancements in sustainable electric mobility

Evidence of two viscous relaxation processes in the collective dynamics of liquid lithium

New inelastic X-ray scattering experiments have been performed on liquid lithium in a wide wavevector range. With respect to the previous measurements, the instrumental resolution, improved up to 1.5 meV, allows to accurately investigate the dynamical processes determining the observed shape of the the dynamic structure factor, $S(Q,\omega)$. A detailed analysis of the lineshapes shows the co-existence of relaxation processes with both a slow and a fast characteristic timescales, and therefore that pictures of the relaxation mechanisms based on a simple viscoelastic model must be abandoned.Comment: 5 pages, 4 .PS figure