bluuebunny/crossref_metadata_2025_split huggingface dataset:
ANALISIS VARIABEL PENYEBAB TIDAK TERCAPAINYA RECOVERY BIJIH TIMAH PADA JIG DALAM PROSES PENCUCIAN DI KAPAL KERUK
Authors: Rande Aprilia 
Published: May 2022

Instalasi pencucian pada Kapal Keruk berperan penting dalam proses produksi mengingat endapan yang terdapat pada penambangan lepas pantai adalah endapan alluvial berupa pasiran. Tujuan penelitian ini dilakukan untuk mengetahui proses recovery bijih timah pada jig dalam proses pencucian di Kapal Keruk dan menganalisis variabel yang menyebabkan tidak tercapainya recovery bijih timah pada jig dalam proses pencucian di Kapal Keruk. Pengaturan variabel-variabel jig memberikan pengaruh besar terhadap material undersize. Banyaknya material undersize akan berpengaruh terhadap recovery bijih timah yang dihasilkan dalam proses pencucian dengan target recovery 95,50 %, sehingga perlu dilakukan optimalisasi jig dengan melakukan perubahan pada variabel jig untuk meningkatkan recovery bijih timah pada Kapal Keruk. Variabel jig pada Kapal Keruk 19 Bangka 2 dilakukan perubahan pada panjang pukulan menjadi lebih besar dari sebelumnya (1 – 2 mm), dengan tujuan menyesuaikan ukuran fraksi diameter timah yang akan dilakukan pencucian (#50 – #70), sehingga meningkatnya recovery sesuai dengan SOP perusahaan. Pengaruh hasil recovery setelah dilakukannya perubahan ukuran variabel panjang pukulan menjadi 96,98 % dari 95,60 %. Tujuan utama perubahan variabel panjang pukulan adalah mengoptimalkan hasil pencucian menjadi lebih baik dan meningkat dari 0,10 % menjadi 1,48 % di atas target SOP.
Kata kunci: Jig, recovery, pencucian, Kapal Keruk.
KARAKTERISTIK MINERALISASI BIJIH EMAS PADA PROSPEK HARGOSARI, KECAMATAN TIRTOMOYO, KABUPATEN WONOGIRI, PROVINSI JAWA TENGAH
Authors: Idrus Arifudin , Hermansyah Wahyu 
Published: May 2022

Tirtomoyo di Kabupaten Wonogiri dikenal sebagai daerah mineralisasi bijih, di mana salah satu prospeknya adalah Hargosari. Belum ada penelitian sebelumnya yang mengungkap bagaimana karakteristik bijih pada prospek ini. ini mineralisasi bijih emas meliputi aspek mineralogi, tekstur, geokimia dan kondisi pembentukannya. Metoda penelitian mencakup pemetaan dan pengambilan sampel, serta sampel terpilih dianalisis petrografi, mikroskopi bijih dan kimia bijih. Batuan induk berupa lava andesit yang termasuk pada Formasi Panggang berumur Oligo-Miosen. Sistem bukaan urat diketahui sebagai tipe jogs membentuk en-´echelon tension gash veins. Tipe alterasi terdiri atas argilik dan propilitik, dengan mineral logam berupa pirit, kalkopirit, sfalerit, galena, emas, perak, krisokola, kovelit dan hematit. Urat kuarsa dengan tebal rerata sekitar 5 cm menunjukkan struktur massive, swarm, low angle veins dan stockwork, serta memiliki tekstur normal banded, crustiform, comb dan sakaroidal. Urat tersebut mengandung logam dasar yang tinggi mencapai 5,45% Cu, 9,9% Pb dan 12,85% Zn, dan logam berharga mencapai 3,85 g/t Au dan 395 g/t Ag. Endapan tersebut diperkirakan terbentuk pada temperatur 250-300°C mengacu pada himpunan mineralnya. Berdasarkan karakteristik tersebut, mineralisasi emas pada prospek Hargosari merupakan epitermal sulfidasi menengah.
Katakunci: karakteristik, emas, epitermal, Hargosari, Wonogiri.
FITOREMEDIASI TANAH TERCEMAR Pb DAN Zn DI TEMPAT PEMBUANGAN AKHIR (TPA) SAMPAH PIYUNGAN, YOGYAKARTA
Authors: Siti Fatimah Kartika Eka Putri Srisena , Budianta Wawan 
Published: May 2022

Tempat Pembuangan Akhir Sampah (TPA) sampah Piyungan di Yogyakarta merupakan salah satu tempat pembuangan sampah di Yogyakarta yang telah mengakibatkan terjadinya pencemaran tanah oleh timbal (Pb) dan Seng (Zn). Penelitian ini bertujuan untuk menganalisis pengaruh karakteristik tanah tercemar yang diambill dari lokasi TPA Piyungan terhadap efektifitas serapan Pb serta Zn oleh tanaman jarak pagar (Jatropha Curcas) dan bayam (Amaranthus Spinosus L.) Percobaan fitoremediasi dilakukan pada polybag yang diisi dengan 2 kg sampel tanah tercemar Pb dan Zn, kemudian percobaan dilakukan di dalam rumah kaca selama 3 bulan, dengan pemanenan yang dilakukan setiap bulan. Pada setiap panen, sampel tanaman dibagi menjadi bagian pucuk (kombinasi antara batang dan daun) serta akar, kemudian dianalisis konsentrasi Pb dan Zn setelah dilarutkan dalam aqua regia. Analisis konsentrasi Pb dan Zn dilakukan dengan menggunakan ICP-AES. Hasil percobaan fitoremediasi menunjukkan bahwa baik kandungan Pb maupun Zn terdeteksi seiring dengan kedalaman sampel tanah yang diambil. Hal tersebut menunjukkan bahwa kandungan Pb dan Zn paling tinggi berada pada lapisan tanah bagian atas. Karakteristik tanah di TPA Piyungan, meliputi: pH, kandungan organic, dan kandungan mineral lempung yang mempengaruhi efektifitas serapan dalam proses fitoremediasi, terutama pada kandungan montmorilonit dalam tanah. Hal ini dikonfirmasi dari hasil perhitungan efisiensi serapan dan perhitungan mass balance serta removal efficiency yang dilakukan yang menunjukkan bahwa tanaman jarak pagar (Jatropha Curcas) dan bayam (Amaranthus Spinosus L.) memiliki nilai yang relatif rendah.
Kata kunci: Fitoremediasi, tanah, pencemaran, timbal, seng.
GUNUNG API PURBA CANDISARI : IDENTIFIKASI AWAL, KARAKTERISASI PEMBENTUKAN, POSISI STRATIGRAFI DAN POTENSI PEMANFAATANNYA
Authors: Oky Sugarbo  
Published: May 2022

Abstrak
Pada Zona Pegunungan Selatan, banyak tersingkap batuan gunung api produk dari busur Gunung Api Tersier. Pada zona tersebut, telah banyak dilakukan penelitian namun penelitian baik tentang keberadaan gunung api purba maupun pusat erupsi purba masih belum dilakukan secara menyeluruh, sehingga perlu dilakukan penelitian lebih lanjut terkait vulkanisme purba Pegunungan Selatan. Maksud penelitian ini adalah melakukan identifikasi awal keberadaan gunung api purba berdasarkan data lapangan dan laboratorium, dengan tujuan untuk mengetahui karakter, genesis, posisi stratigrafi, dan potensi dari gunung api purba yang menghasilkan banyak batuan gunung api. Metode penelitian yang dilakukan berupa metode pemetaan permukaan yang didukung dengan data laboratorium berupa petrografi dan geokimia batuan menggunakan X-Ray Flourecence. Pada daerah penelitian, ditemukan adanya indikasi gunung api purba berdasarkan data citra, litologi, stratigrafi, petrograf, dan geokimia, dengan asosiasi fasiesnya berada pada fasies proksimal bagian atas. Secara stratigrafi, batuan Gunung Api Purba Candisari berada di bawah Formasi Semilir namun bukan bagian dari Formasi Kebo-Butak. Keberadaan batuan gunung api yang melimpah dapat dimanfaatkan sebagai bahan galian C. Selain itu, perlu dilakukan studi lanjut tentang adanya alterasi hidrotermal pada daerah penelitian yang kemungkinan dapat dimanfatkan warga sekitar karena batuan yang teralterasi dapat memiliki nilai ekonomi.
Kata kunci: lava, genesis, vulkanisme, purba, Candisari.
PENERAPAN KECERDASAN BUATAN PADA PENILAIAN KELAYAKAN EKONOMI TAMBANG BATUBARA
Authors: Sidiq Hidayatullah , Heriyadi Nur Widi Astanto Agus Tri 
Published: May 2022

Metode penilaian kelayakan ekonomi sangat penting dalam menentukan nilai suatu proyek. Adanya ketidakpastian yang tinggi dalam industri pertambangan baik dari segi teknis maupun non teknis, menyebapkan risiko proyek pertambangan relatif lebih tinggi dibandingkan dengan industri lain. ketidakpastian dimodelkan dengan suatu deret probabilitas yang tidak terputus. Distribusi ini banyak digunakan untuk memodelkan ketidakpastian dari faktor non teknis seperti harga komuditas. Untuk menggambarkan ketidakpastian dari input variabel dalam simulasinya depat menggunakan teknik simulasi monte carlo. Selain itu untuk memprediksi harga jual batubara menggunakan algoritma kelelawar. Hasil penelitian menunjukan bahwa prediksi harga batubara adalah salah satu parameter yang sulit diprediksi. Untuk menentukan harga jual dapat menggunakan pendekatan prediksi dengan bantuan kecerdasan buatan. Prediksi harga menggunakan simulasi monte carlo menghasilkan harga jual batubara dengan kalori 5700 kcal/Kg adalah $ 42,2 per ton. Sedangkan jika menggunakan algoritma kelelawar adalah $42,18 per ton. Analisis kelayakan proyek tambang menggunakan metode DCF dengan NPV yang paling maksimal berada pada stripping ratio 2,5 dengan volume batubara sebesar 11 juta ton.
ANALISIS SENSITIVITAS PADA PEMODELAN AIRTANAH MENGGUNAKAN METODE FINITE DIFFERENCE PADA KONDISI STEADY STATE DI KAB BANTUL PROV. YOGYAKARTA
Authors: Satria fitrio  , Agung C Tedy , Dwinagara Barlian , Ansori Muhammad Iqbal 
Published: May 2022

Groundwater modeling is a form or digital image both 2D and 3D that can represent or approach the real form in the field. Groundwater modeling is made to show an overview or system of water flow under the ground surface. Groundwater is an important component in the hydrogeological cycle and groundwater management is very necessary so that the sustainability or the groundwater order system can be well maintained in the future. The purpose of this study is to determine the modeling of groundwater and groundwater distribution patterns from the calibration process in steady state conditions using the MODFLOW program. Groundwater modeling calibration used aims to validate the suitability of the model results with field conditions. The calibration is carried out using shallow wells of at least 67 community wells by combining topographic parameters, hydraulic conductivity, recharge, storativity, constant head, and ground water level that have been processed in the Modflow computational program. The results of the sensitivity analysis of modeling calibration are carried out into several stages of calibration scenarios so that the results that are closest to the standard criteria for groundwater models are obtained.
Keyword: Groundwater modeling, Modflow, Calibration, groundwater, steady state
PERANCANGAN SISTEM BRINE COOLING PADA SHOWCASE DAN KABIN HIDROPONIK UNTUK TANAMAN KANGKUNG (IPOMOEA AQUATICA)
Authors: Lukitobudi Arda Rahardja , Prasetyo Bowo Yuli , Harish M. Fasya Nur , Fadhil Dimas Alif 
Published: May 2022

Limited area and pollution in the city and also weather problem can become an obstacle to planting kale (Ipomoea Aquatica). Post harvest storage of kale also usually does not conditioned which quickly wilted and not fresh. To create an optimum environment, it was necessary to control environment factors such as air temperature, humidity, light intensity, growing media temperature and humidity, and the availability of nutrients [2]. Tofu and wood waste as a hydroponic nutrients [1] not all area were available so in this research AB Mix nutrient was used. In this research, refrigerated showcase by brine cooling was used [3][4]. Hydroponic planting system method used in this research was Deep Flow Technique which the kale (Ipomoea Aquatica) was planted in a water layer 4-6 cm deep in conditioned showcase of 20-30 0C and 60% humidity. Brine cooling was used to condition the showcase from seed to post harvest and was observed its growth. Post harvest conditioned storage was also complete the showcase more durable.
By brine cooling system to cool brine in the range of 70C to 170, the product storage cabin was maintained at 8,70C to 10,50C and the showcase cabin was maintained at 20,40C to 23,60C. The brine cooling system has COPactual of 3,98 and COPcarnot of 6,65 with system efficiency of 59,8%.

Keywords: Hydroponic, Ipomoea Aquatica, showcase, brine cooling, Deep Flow Technique.
Pre-Eruptive Magma Configurations and Petrogenetic Relationships of the Rattlesnake Tuff, Oregon–Insights From Spectacularly Banded High-Silica Rhyolite Pumices
Authors: Swenton Vanessa M. , Streck Martin J. 
Published: May 2022

The 7.1 Ma Rattlesnake Tuff (RST) of eastern Oregon is a widespread and voluminous (&gt;300 km3) ignimbrite composed of 99% crystal poor (≤1%) high-silica rhyolite (HSR) and &lt;1% dacites. Basaltic andesitic to basaltic inclusions within dacites are samples of underpinned mafic magmas. The RST HSR is comprised of five increasingly evolved compositional Groups (E–A), and HSR pumices range from white to dark grey, often co-mingled in spectacular banded pumices. Previously, Groups were interpreted as rhyolites generated by crystal fractionation within a single reservoir, where more evolved rhyolite melts formed from relatively less evolved rhyolite parents. To reassess compositional HSR Groups and their implications for tapping a single or multiple rhyolite reservoirs as well as reevaluating the petrological relationships among groups, we focus on large banded pumices for geochemical analysis. Statistical analysis of existing and new data verified these five compositional Groups and gaps, best characterized by variations in Ba, Eu/Eu*, Eu, FeO*, Hf, and Zr. Wet-liquidus temperatures, storage temperatures, and storage pressures calculated for all HSR Groups indicate similar pre-eruptive conditions (∼6.1–7.5 km depth; storage temperatures of ∼805–895°C). Differentiation trends, trends in storage pressure and temperature, and lack of crystal-rich tuff or country rock corroborate existing models for HSRs that involve a single, density-stratified magma reservoir prior eruption. Density differences are sufficient to prevent convection between layers of HSRs in a single reservoir when water content increases from 2–4 wt% from Groups E–A. However, if HSRs do not represent a liquid line, it is possible to generate HSRs through batch melting of various regional country rock. Yet, HSRs would still accumulate within the same storage zone, where density variations kept HSRs from mixing until eruption when these banded pumices formed. In either scenario, our study underscores the significance of water content and density variations for accumulating rhyolite magmas in a contiguous magma body without mixing. This has implications for other compositionally heterogenous rhyolitic ignimbrites where natural samples do not provide comparable evidence to argue for pre-eruptive confocal storage of different rhyolite magmas as is the case for the Rattlesnake Tuff.
Nightshift Work and Nighttime Eating Are Associated With Higher Insulin and Leptin Levels in Hospital Nurses
Authors: Molzof Hylton E. , Peterson Courtney M. , Thomas S. Justin , Gloston Gabrielle F. , Johnson Russell L. , Gamble Karen L. 
Published: May 2022

BackgroundCircadian misalignment between behaviors such as feeding and endogenous circadian rhythms, particularly in the context of shiftwork, is associated with poorer cardiometabolic health. We examined whether insulin and leptin levels differ between dayshift versus nightshift nurses, as well as explored whether the timing of food intake modulates these effects in nightshift workers.MethodsFemale nurses (N=18; 8 dayshift and 10 nightshift) completed daily diet records for 8 consecutive days. The nurses then completed a 24-h inpatient stay, during which blood specimens were collected every 3 h (beginning at 09:00) and meals were consumed at regular 3-h intervals (09:00, 12:00, 15:00, and 18:00). Specimens were analyzed for insulin and leptin levels, and generalized additive models were used to examine differences in mean insulin and leptin levels.ResultsMean insulin and leptin levels were higher in nightshift nurses by 11.6 ± 3.8 mU/L (p=0.003) and 7.4 ± 3.4 ng/ml (p=0.03), respectively, compared to dayshift nurses. In an exploratory subgroup analysis of nightshift nurses, predominately eating at night (21:00 – 06:00) was associated with significantly higher insulin and leptin levels than consuming most calories during the daytime (06:00 – 21:00).ConclusionsIn our study of hospital nurses, working the nightshift was associated with higher insulin and leptin levels, and these effects were driven by eating predominately at night. We conclude that although nightshift work may raise insulin and leptin levels, eating during the daytime may attenuate some of the negative effects of nightshift work on metabolic health.
Moisture Stability of Sulfide Solid-State Electrolytes
Authors: Yersak Thomas A. , Zhang Yubin , Hao Fang , Cai Mei 
Published: May 2022

In this report we detail a comprehensive study on the moisture stability of sulfide solid-state electrolytes in dry room environments. Although sulfide SSEs have many favorable attributes, this class of materials suffers from poor stability with water. Sulfide SSEs react with water to form gaseous H2S and a variety of solid byproducts like Li3PO4 and LiOH, which go on to increase the interfacial impedance of solid-state batteries. Lab-scale research typically utilizes gloveboxes with &lt;1 ppm water, however, the large-scale manufacturing of Li-ion batteries occurs in −40°C dewpoint dry rooms with around 126 ppm water. Consequently, the moisture stability of sulfide SSEs must be addressed if the manufacture of solid-state batteries based on sulfide SSEs is to be scaled up. Here, we are the first to characterize the moisture stability of sulfide SSEs according to both H2S and the degradation of ionic conductivity at different moisture setpoints ranging from −76°C to −40°C dewpoint. A variety of different SSE compositions are studied; namely, (Li2S)75(P2S5)25, (Li2S)70(P2S5)30, (Li2O)7(Li2S)68(P2S5)25, (Li2O)7(Li2S)63(P2S5)30, and (Li2S)75(P2S5)25 + 20 mol% LiI. We find that moisture stability improves with 75 mol% Li2S modifier content and the introduction of a Li2O co-modifier. After a 30 min exposure in a −40°C dewpoint dry room environment we found that (Li2S)75(P2S5)25 + 20 mol% LiI powder generated 0.1 cc/g H2S and its ionic conductivity decreased by over 50%. However, when SSE powder was exposed as a slurry in a dodecane carrier the same SSE composition generated 0 cc/g H2S and its ionic conductivity only dropped by 14%. Our results show that sulfide SSEs have acceptable moisture stability when appropriately processed in a dry room environment.
Hemodynamic Characteristic Analysis of Aneurysm Wall Enhancement in Unruptured Middle Cerebral Artery Aneurysm
Authors: Zhong Weiying , Du Yiming , Kuang Hong , Liu Ming , Xue Feng , Bai Xue , Wang Donghai , Su Wandong , Wang Yunyan 
Published: May 2022

Background and PurposeAneurysm wall enhancement (AWE) on vessel wall magnetic resonance imaging has been suggested as a marker of the unstable status of intracranial aneurysm (IA) and may predict IA rupture risk. However, the role of abnormal hemodynamics in unruptured IAs with AWE remains poorly understood. This study aimed to determine the association between abnormal hemodynamics and AWE in unruptured middle cerebral artery (MCA) aneurysms.MethodsA total of 28 patients with 32 bifurcation aneurysms of the middle cerebral artery&gt;3mm in size were retrospectively selected for this study. Vessel wall magnetic resonance images were reviewed, and the AWE pattern of each aneurysm was classified as no AWE, partial AWE, and circumferential AWE. Computational fluid dynamics were used to calculate the hemodynamic variables of each aneurysm. Univariate and multivariate analyses investigated the association between AWE and hemodynamic variables.ResultsAWE was present in 13 aneurysms (40.6%), with 7 (21.9%) showing partial AWE and 6 (18.7%) showing circumferential AWE. Kruskal–Wallis H analysis revealed that hemodynamic variables including wall shear stress (WSS), oscillatory shear index, aneurysm pressure (AP), relative residence time, and low shear area (LSA) were significantly associated with AWE (p &lt; 0.05). Further ordinal logistic regression analysis found that WSS was the only factor with a significant association with AWE (p = 0.048); similar trends were identified for LSA (p = 0.055) and AP (p = 0.058). Spearman's correlation analysis showed that AWE was negatively correlated with WSS (rs = −0.622, p &lt; 0.001) and AP (rs = −0.535, p = 0.002) but positively correlated with LSA (rs = 0.774, p &lt; 0.001).ConclusionLow wall shear stress, low aneurysm pressure, and increased low shear area were associated with aneurysm wall enhancement on vessel wall magnetic resonance imaging in unruptured cerebral aneurysms. These abnormal hemodynamic parameters may induce inflammation and cause aneurysm wall enhancement. However, the association between these parameters and their underlying pathological mechanisms requires further investigation.
Factors Influencing Social Participation Among Persons With Neuromyelitis Optica Spectrum Disorders: A Cross-Sectional Study
Authors: Jia Mengmeng , Fan Ping , Ning Lin , Ruan Hengfang , Wang Tong , Qiu Wei , Li Huijuan , Li Kun 
Published: May 2022

BackgroundNeuromyelitis optica spectrum disorders seriously hinder social participation. Only clarifying the status of social participation and the factors most strongly influencing it can promote better-targeted support for those with neuromyelitis optica spectrum disorders.ObjectivesTo explore the factors influencing social participation among persons with neuromyelitis optica spectrum disorders.Methods138 persons with neuromyelitis optica were recruited by convenience sampling. They completed the Impact on Participation and Autonomy Questionnaire, and were rated using the Barthel index, the Beck Anxiety Inventory and the Beck Depression Inventory. The data were used to evaluate a generalized linear model predicting social participation.ResultsThe respondents mostly perceived good or very good possibilities of social participation, but participation outdoors and in social relations were considered more restricted. Ability in the activities of daily living, education level, bladder and bowel dysfunction, and depression were four significant predictors of social participation.ConclusionsStrengthening training in the activities of daily living, continuing education, giving positive psychological support and helping with bladder and bowel problems may help to promote social participation among those with neuromyelitis optica spectrum disorders.
Differences in Neuropathic Pain and Radiological Features Between AQP4-ON, MOG-ON, and IDON
Authors: Kang Hao , Qiu Huaiyu , Hu Xiaofeng , Wei Shihui , Tao Yong 
Published: May 2022

PurposeThe purpose of this study was to investigate pain and radiological features of different types of first-episode demyelinating optic neuritis (ON).MethodsEighty-three patients presenting with first-episode aquaporin-4 (AQP4) antibody-associated ON (AQP4-ON; n = 28), myelin oligodendrocyte glycoprotein (MOG) antibody-associated ON (MOG-ON; n = 26) and idiopathic demyelinating optic neuritis (IDON, n = 29) were included in this retrospective case-control study. We assessed optic nerve lesions on magnetic resonance imaging (MRI), acute pain associated with onset of optic neuritis and clinical characteristics of those ON patients with different serum autoantibody status.Results24 AQP4-ON patients (85.75%), 23 MOG-ON patients (88.5%) and 24 IDON patients (82.8%) suffered from ON-associated pain. MOG-ON had mostly retro-orbital pain; AQP4-ON and IDON had mostly neuropathic pain. In addition, pain was more severe in AQP4ON patients than in other ON patients. In MRI, bilateral involvement was more common in AQP4-ON than IDON (26.9 and 3.7%); radiological optic nerve head swelling was more common in MOG-ON than in AQP4-ON and IDON (68.0 vs. 23.1 vs. 25.9%). MRI lesion in peri-optic nerve sheath was more common in AQP4-ON (53.8 vs. 16.0 vs. 3.7%). In 70 patients with ON-associated pain, gadolinium enhancement of orbital optic nerve was most common in MOG-ON patients (82.4 vs. 55.0 vs. 33.3%, P = 0.018), and enhancement of optic chiasma was most common in AQP4-ON patients (40.0 vs. 5.9 vs. 6.7%, P = 0.015). Perineural and orbital enhancement was observed only in patients with MOG-ON (P &lt; 0.001). The length of enhancement was longer in AQP4-ON patients than in MOG-ON and IDON patients.ConclusionPain is a common symptom in patients with all types of demyelinating ON. AQP4-ON is frequently associated with severe ON-associated pain and longitudinally extensive optic nerve inflammatory lesions. Intra-orbital and peri-optic inflammation were more frequently observed in patients with MOG-ON, which was closely related to optic disc swelling and retro-orbital pain provoked by eye movements.