Elastomer Termoplastik Sebagaiaditif Peningkat Viskositas Pelumas Mineral

ELASTOMER TERMOPLASTIK SEBAGAIADITIF PENINGKAT VISKOSITAS PELUMAS MINERAL. Penggunaan elastomer termoplastik (ETP) sebagai aditif peningkat viskositas minyak mineral berindeks viskositas tinggi (HVI) telah dilakukan. Sebagai bahan elastomer termoplastik digunakan kopolimer radiasi lateks karet alam-metil metakrilat (LKA-MMA). Bahan ETP dilarutkan dalamminyak lumas dasar HVI dengan variasi suhu dan pelarut. Hasil penelitian menunjukan bahwa pelarutan langsung memerlukan suhu 80 oC dan waktu 12 jam. Penggunaan xilena sebagai pelarut antara, mengefisienkan metode pelarutan karena tidak diperlukan pemanasan dan waktu pelarutan lebih pendek. Koefisien viskositas kinematik dan indeks viskositas dari minyak lumas mineral yang mengandung xilena tidak berbeda secara signifikan dibandingkan minyak lumas yang tidak menggunakan xilena sebagai pelarut antara. Maksimum pelarutan ETP pada minyak lumas mineral adalah 10 % tanpa pelarut antara

Pengaruh Media Kokami (Kotak dan Kartu Misterius) terhadap Keterampilan Berpikir Kritis dan Motivasi Belajar Siswa Kelas VIII SMP Negeri 19 Mataram Tahun Pelajaran 2017/2018

Tujuan penelitan ini adalah mengetahui pengaruh media Kokami (Kotak dan Kartu Misterius) terhadap keterampilan berpikir kritis dan meningkatkan motivasi belajar siswa di SMP Negeri 19 Mataram Kelas VIII tahun pelajaran 2017/2018. Penelitian ini merupakan penelitian pre-eksperimen, dengan desainone-group pretest-posttest design. Subjek dalam penelitian ini adalah seluruh siswa kelas VIII SMP Negeri 19 Mataram. Sampel penelitian diambil secara purposive sampling dan kelas VIIID ditentukan sebagai sampel. Instrumen yang digunakan berupa tes soal dan angket yang telah diuji kelayakannya.Dalam pengukuran motivasi digunakan teknik analisis data berupa kualitatif, diperoleh peningkatan untuk perhatian, relevansi, percaya diri dan kepuasan dengan menggunakan N-Gain masing – masing sebesar 0,83, 0,68, 0,86 dan 0,82 dengan kategori tinggi kecuali relevansi kategori sedang . Data yang terkumpul sebelumnya di uji normalitasnya. Pada uji normalitas pre test diperoleh x2 hitung 1,096 dengan x 2 tabel 11,07 sedangkan data post test di peroleh x2 hitung 10,14 dengan x2 tabel 11,07 (x hitung x tabel 2 2 ) maka data dinyatakan terdistribusi normal pada taraf signifikan 5%. Pengujian hipotesis dengan menggunakan uji-t diperoleh nilai 14,6 hitung t dan 2,03 tabel t ( thitung > ttabel ) menunjukan bahwa hipotesis nol (Ho) ditolak dan hipotesis alternatif (Ha) diterima menyatakan ada perbedaanketerampilan berpikir kritis dan motivasi belajar siswa sebelum dan setelah diajarkan menggunakan media kokami (kotak dan kartu misterius). Berdasarkan beberapa analisis yang telah dilakukan dapat disimpulkan bahwa media pembelajaran menggunakan kokami (kotak dan kartu misterius) dapatmeningkatkan motivasi dan keterampilan berpikir kritis IPA fisika siswa SMP Negeri 19 Mataram Tahun Pelajaran 2017/2018

Blending PEG-based polymers and their use in surface micro-patterning by the FIMIC method to obtain topographically smooth patterns of elasticity

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.We have designed and fabricated a library of polyethylene glycol (PEG)-based polymer blends, including blends of two PEG-based polymers that are liquid at room temperature where the optimisation of the blending method allows for the incorporation of higher molecular-weight PEG-based polymers which are solid at room temperature. The absence of a solvent in these blends makes them perfect candidates for use in our recently developed Fill-Molding in Capillaries (FIMIC) patterning method. As our FIMIC samples have shown to be not completely smooth (a small topography up to several nanometers has been seen previously), and this is likely to affect the cellular behaviour, we have improved our technique in order to obtain virtually smooth samples that exhibit a pattern of elasticity only. It is demonstrated that, by taking advantage of the differential swelling of the pattern components, we can level out the undesired topographic difference. In particular, by employing blends of materials, (1) the swelling degree of each component can be fine-tuned to even out any topography and (2) the use of the same blends in the sample, yet with varying cross-linker amounts, ensures the swelling degree and elasticity change without changing the surface chemistry significantly. Genuine, binary patterns of elasticity can thus be fabricated, which are a great asset to study cell migration phenomena in systematic detail.DFG, EXC 314, Unifying Concepts in Catalysi

Appendicular mucocele. Clinical case

Scopul lucrării. Mucocelul apendicular este o entitate patologică caracterizată prin dilatarea chistică a apendicelui, datorită secreției anormale de mucinos apendicular. Prezintă incidența scăzută, secundar afecțiunilor benigne (hiperplazie mucinoasă și chistadenom) sau maligne (chistadenocarcinom). Materiale și metode. Am analizat cinci pacienți tratați pentru mucocel apendicular în perioada 2012-2023 în Clinica Chirurgie nr.2, USMF ,,N.Testemițanu,, cu vârsta cuprinsă între 24-92 de ani și evaluată modalitatea de diagnostic și tratament chirurgical. Rezultate. Manifestările clinice au fost variate, nespecifice, frecvent au simulat alte afecțiuni chirurgicale abdominale. Examenul preoperator imagistic, ecografic de rutină şi tomografia computerizată în 3 cazuri au confirmat mucocelul apendicular. Diagnosticul a fost confirmat intraoperator, volumul intervenției chirurgicale fiind rezolvat individual. Studiul anatomopatologic a pieselor operatorii a stabilit diagnosticul etiologic și histopatologic. Explorarea intraoperatorie a organelor cavității peritoneale și a bazinului mic a fost obligatorie în diagnosticul diferențial cu formațiunile chistice ale anexelor uterine și ale organelor cavității abdominale. Concluzii. Mucocelul apendicular se referă la bolile chirurgicale rare, manifestând un tablou clinic nespecific. Explorarea clinicimagistică, histopatologică minuțioasă a fiecărui pacient, determină corect strategiile chirurgicale.Aim of study. Appendicular mucocele is a pathology characterized by cystic dilatation of the appendix, due to abnormal secretion of appendicular mucinous. It has low incidence, secondary to benign (mucinous hyperplasia and cystadenoma) or malignant (cystadenocarcinoma) conditions. Materials and methods. We analyzed five patients treated for appendicular mucocele in the period 2011-2023 in Surgery Clinic no.2, USMF,, N. Testemitanu,, aged between 24-92 years and evaluated the method of diagnosis and surgical treatment. Results. Clinical manifestations were varied, nonspecific, and frequently simulated other abdominal surgical conditions. Preoperative imaging, routine ultrasound examination and computed tomography in 3 cases confirmed the appendicular mucocele. The diagnosis was confirmed intraoperatively, the volume of surgical intervention being solved individually. Anatomopathological examination of the operative parts established the etiological and histopathological diagnosis. Intraoperative exploration of the organs of the peritoneal cavity and small pelvis was mandatory in differential diagnosis with cystic formations of the uterine appendages and organs of the abdominal cavity. Conclusions. Appendicular mucocele refers to rare surgical diseases, manifested by a nonspecific clinical picture. The thorough clinical – imaging, histopathological exploration of each patient correctly determines surgical strategies

Social Networks and Adaptation Strategy of Migrant From Lampung In The Village of Jayamukti, Center Cikarang Subdistrict, Bekasi District, West Java

Tingkat pertumbuhan penduduk meningkat secara cepat pada beberapa tahun terakhir menimbulkan permasalahan pada ketenagakerjaan. Pertumbuhan penduduk yang tidak didukung dengan peningkatan sumberdaya dan lapangan pekerjaan menambah jumlah pengangguran. Kondisi tersebut memacu penduduk untuk melakukan migrasi. Perpindahan penduduk dipengaruhi oleh faktor pendorong dari daerah asal, diantaranya yakni terbatasnya pekerjaan dan juga faktor penarik dari daerah tujuan, salah satunya lapangan pekerjaan yang lebih banyak. Fenomena perpindahan penduduk di Indonesia umumnya membentuk siklus dimana migran yang kaya secara ekonomi dan sosial akan memengaruhi keluarga mereka, saudara atau teman untuk ikut bermigrasi. Situasi yang berbeda dan kondisi pada daerah tujuan mendorong mereka untuk beradaptasi sebagai strategi bertahan hidup. Jaringan sosial sangat penting bagi para migran di daerah tujuan

New evidence of the Green Tuff deposits and post-caldera, recent explosive volcanic activity at Pantelleria volcano (Sicily Channel, Italy) recorded in near-vent marine areas

The record of the explosive activity of Pantelleria volcano is well documented by several distal tephra collected in various areas in and around the Mediterranean, while few tephrochronological studies exist on proximal marine areas. In this paper, we investigate three selected coring sites from the northern shoulder of the Pantelleria graben, about 15–30 km from the island, in near-vent position with respect to that volcanic source. Our multiproxy analyses revealed nine tephra layers, totally composed of juvenile materials, mostly ash and pumice fragments, as well as a coarse-grained tephra deposit at the bottom of one of the cores. The major element composition of glass shards indicates a very homogeneous geochemical composition for the tephra layers, suggesting their primary origin. Using litho-stratigraphic and paleoenvironmental proxies, we associated the tephra layers to the latest (<∼13.7 ka) explosive activity of Pantelleria. The coarse-grained deposit, instead, due to its distinctive composition is considered to represent the near-vent, marine equivalent of the distal Y-6 tephra layer, related to the ∼45 ka old co-ignimbrite fallout deposit of the Green Tuff event. The geochemical characterization of such deposit, mostly rhyolitic and partly trachytic, appears to enlarge the bimodal composition recorded in other distal tephra (Y-6) reported in the literature, highlighting the potential of near-vent record in providing additional information on the eruptive history

Evaluation of Groundwater potential Zones using RS and GIS Application in Malattar watershed, Tamil Nadu, India

Groundwater is one of the major sources of water both in the semi-arid and arid regions like Tamil Nadu, India. It is of fundamental importance to any social or economic development. In recent decades, as surface water supplies have been depleted or contaminated and hence more attention has been given to groundwater resources. The advances in the technology especially in the field of remote sensing satellite technology, geophysics, etc. have resulted in enormous increase in the extraction of groundwater. The reservoirs and tanks of the surface water body mainly depending on rainfall.  Due to various reasons the capacity of these structures is also reduced. Hence the storage conditions of these structures are poor during monsoon seasons. In many parts of the state, the declination of groundwater level is a major concern because of continuous pumping of groundwater and poor storage in tanks and reservoirs. Variation of temperature, wind velocity, sunshine hours and evapotranspiration were analyzed. Seasonal average rainfall for 46 years was used to analyze spatial distribution. Geomorphology, land use and lineaments derived from satellite data and geology and soil prepared from district resource maps. Depth to bed rock and weathered rock derived from geophysical survey data to evaluate aquifer thickness. Groundwater potential zonation map was generated using Geographical Information system (GIS) by integration of various thematic maps in the Malattar watershe