bluuebunny/crossref_metadata_2025_split huggingface dataset:
Failure Analysis in Lacing Wire Of Last Stage Low Pressure Steam Turbine Blade
Authors: Kongkong A M , Setiawan H , Miftahul J , Laksana A R , Djunaedi I , Suwarno  
Published: March 2021

Abstract
The present paper studies a root cause of failure analysis of lacing wire used in the last stage blade of low pressure (LP) steam turbine. The lacing wire is made of Stainless Steel Grade 17-4 PH with a diameter of 1.4 mm. The failure occurred after the unit had been operated for 4 years. The fault occurred several times during the operation periods. The failure location is near the tack weld which has functions as a stopper between the lacing wire and the stub. Macro fractography, light optical microscope and scanning electron microscope were used to examine the fracture surface and microstructure closed to the failures. The cyclic stress was evaluate using harmonic analysis simulation using FEA (finite element analysis) Ansys 2019 R2. The benchmark that is indication of fatigue failure was clearly visible. It is concluded that the failure mechanism is fatigue failure with crack initiation. Improper maintenance procedures especially welding procedures trigger an initial crack and then the initial crack gets a concentrated cyclic load causing lacing wire broken.
Numerical Study to Improve Fluid Flow Patterns in HRSG by using a Turning Vane and a Combination of using a Turning Vane with Transition Zone Geometry Modification
Authors: Yuwono E A , Widodo W A 
Published: March 2021

Abstract
Since operated from 1995 until 2018, the total steam production of HRSG 1.1 has decreased by 6.34 % and exhaust gas outlet temperature increased by 40.86 °C. From previous studies on HRSG it can be assumed that flue gas flows at HRSG 1.1 has nonuniform velocity and temperature distribution. This research is carried out by modeling and simulating HRSG as porous media using Computational Fluid Dynamic (CFD) software. The simulation will be carried out on a 3D model with the steady-state condition, use energy model, a heat exchanger (HE) model, and standard k-ε as a turbulence viscous model. Energy absorption in HE will be modeled by an ungroup macro model with fixed inlet temperature and NTU model. Simulations in HRSG are implemented at a corner angle of 6 degrees (original), adding a turning vane on the inlet duct and combination adding a turning vane on inlet duct with 12 degrees corner angle on transition zone. Model validation was accomplished comparing simulation data to power plant data. The result shows adding a corner angle in the transition zone and installing a turning vane in the curve bend minimizes secondary flow in the transition zone. Heat absorption increases 0.008% and exhaust gas outlet temperature decrease 0.04% compared to the existing model.
Strategic Framework Supply Chain through Kraljic Purchasing Portfolio in O&M Power Plant Company
Authors: Zemmy M , Setiyowati Rianti 
Published: March 2021

Abstract
This paper aims to determine a flexible and extensible model (strategic framework) in classifying the needs of materials/services as a procurement guideline for the company’s operating and maintenance service providers (O&M) power plants. PT PJB Services is a service provider of O&M which leads the market by managing power plants scattered across various islands facing problems related to the delay supply of spare parts. One of the efforts that can be done is to increase the efficiency of the procurement process by determining the model to identify important supply chains. This Model was obtained by the analysis of purchase portfolio using the Kraljics matrix. The design is based on a spare part position in the Kraljic portfolio Matrix consisting of a dimension of risk procurement and impact profit. The application of this model enables the determination of the critical company in the high lead time problem and the provider of materials/services involved. Analysis of critical needs position (including the suppliers involved) in the Kraljic matrix allows can be defined some strategies that may be applied to the lead time reduction.
Efforts to Reduce SO2 Emission in Paiton Coal-Fired Power Plant
Authors: Andri  , Basuki B H , Seputro E S , Kusuma E 
Published: March 2021

Abstract
Several breakthrough methods are needed to reduce the exhaust emissions of coal combustion in the boiler in order to meet the environmental quality standard requirements. The implementation of coal mixing is one of the short-term programs to reduce SO2 emissions, which is carried out by mixing several types of coal which have different calorific values and sulfur content to obtain the right coal mixture so that coal combustion will produce low SO2 emissions. Supply of coal with low sulfur content is getting smaller due to limited reserves, which causes the coal switching method will no longer be effective. Installation of flue gas desulfurization (FGD) facilities is an effective way to reduce SO2 emissions. Considering the condition and location of the Paiton 1-2 coal-fired power plant, the seawater desulfurization system is the most appropriate to be implemented because it is close to abundant seawater sources and the system has high reliability and effective economic value. By implementing flue gas desulphurization, SO removal efficiencies will be more than 95%.
Microstructure, Morphology, and Dielectric Properties of Ba1-xLaxTiO3 with Variation Mole Concentration of Lanthanum by Co-Precipitation Method
Authors: Ulfa U , Iriani Y , Kusumandari K 
Published: March 2021

Abstract
This study aims to determine the microstructure, morphology, and dielectric properties of Ba1-xLaxTiO3 modified with variations moles concentration of 10% and 15% Lanthanum at sintering temperatures of 1300°C and 1400°C for 4 hours. Ba1-xLaxTiO3 was synthesized using the co-precipitation method. The results of characterization using X-Ray Diffraction (XRD) showed that the greater concentration of La mole caused a diffraction angle shift to the right. The crystallite size decrease asthe increasing concentration of La mole and sintering temperature. The smallest crystallite size (36.63 nm) belong to a sample of Ba0,85La0,15TiO3 sintered at 1400°C. The intensity and the crystallinity decreased with increasing concentration of La mole. Scanning Electron Microscopy (SEM) photographs showed that grain size got smaller with increasing La mole concentration. The dielectric constant obtained from the results of characterization using a Resistance Inductance Capacitance meter (RLC meter) showed that the higher the concentration of La mole added, the greater the dielectric constant produced. The highest dielectric constant was 414 belonged to the sample Ba0,85La0,15TiO3 sintered at 1400°C.
Fabrication of PVDF/SiO2 Nanofiber Membrane as A Separator of Li-ion Battery by Double Jet Sprayers Electrospinning Method
Authors: Widiyandari H , Putra O A , Purwanto A , Subagio A 
Published: March 2021

Abstract
The temperature of the lithium-ion battery while running the electric vehicle becomes a severe safety issue. One way to keep the battery work at high temperatures is by a modified battery separator. The separator was used as a component to secure the battery by preventing short circuit current between the electrodes of opposite polarity. This current research reported the high-temperature shrinkage and excellent mechanical strength membrane separator based on PVDF/SiO2 nanofiber produced by double jet sprayers electrospinning method on rotating cylinder collectors. The independent variable in this research was the variation of a SiO2 polymer at 0 ppm, 500 ppm, 1000 ppm, and 3000 ppm. The results of PVDF/SiO2 nanofiber formed have beaded fiber structure with the average size of fiber’s diameter of ~192 nm. The highest amount of SiO2 addition (SiO2 3000 ppm) on PVDF nanofiber’s membrane causes an increase of porosity up to 69%. The addition of SiO2 also strengthens its mechanical and thermal shrinkage properties to 150°C. In the testing of the charge-discharge battery using separator PVDF/SiO2 nanofiber, the specific capacity value is 181 mAh/g.
A comparative study on the self-cleaning behavior and antibacterial activity of Portland cement by addition of TiO2 and ZnO nanoparticles
Authors: Dehkordi Bahzad Abasifard , Nilforoushan Mohammad Reza , Talebian Nasrin , Tayebi Morteza 
Published: March 2021

Abstract
In the present study, the photocatalytic effect of the addition of nano-TiO2/ZnO particles with different molar ratios of polyethylene glycol on the self-cleaning behavior and antibacterial activity of Portland cement was investigated to evaluate its potential for dye decolorization, and inactivation of Escherichia coli and Streptococcus mutans. Moreover, the effect of PEG addition on the hydration and tensile strength properties of the cement samples was evaluated. Furthermore, to study the self-cleaning behavior of the cement samples, an azo dye was selected as an organic pollutant. The modified cement samples were characterized using x-ray diffraction, Fourier-transform infrared spectroscopy, energy-dispersive x-ray spectroscopy, and scanning electron microscopy to assess the pozzolanic reactivity of the cement paste in the presence of TiO2 and ZnO nanoparticles. The results showed that the bactericidal properties of the modified cement specimens were dependent on the hydration time and composition of the samples. Accordingly, the maximum inhibitory effect was observed for the specimens hydrated for 7 d. Additionally, the surface of the samples was able to effectively decompose the azo dye. This novel modified cement has a promising potential to be used as a self-cleaning and antibacterial coating for urban constructions.
The investigation of chemical vapor deposited copper-based niobium films
Authors: Li Min , Pu Guo , Luo Yuchuan , Ye Zongbiao , Wei Jianjun , Chen Shuwei , Wu Andong , Yang Li , Zhang Kun , Gou Fujun , Zhu Tongtong , Tan Teng , He Yuan , Guo Hengxin , Chen Jianjun , Chen Bo , Wang Hongbin 
Published: March 2021

Abstract
The deposition of niobium film on copper with excellent superconducting property at low-temperature conditions, used as superconducting radio frequency (SRF) cavity, is a serious and urgent technical problem to be solved at present. In this work, copper-based niobium (Nb) films with a thickness of 1.5–1.8 um, regulating the deposition temperature parameters and gas flow velocity in a tube furnace, were prepared by low-temperature chemical vapor depositing (CVD) method from the reaction between H2 and Niobium chloride (NbCl5) under pure Ar atmosphere. Fabricated Nb films were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy, respectively. The results showed that the excellent crystalline quality and superconductive performance of Nb films were generated successfully by CVD at low temperatures of 650 °C–700 °C. The preparation process was optimized during deposition and the formation mechanism of Nb films was also discussed in detail. The magnetic moment versus temperature of the Nb sample prepared at 700 °C was also measured and the well-prepared Nb film deposited in the boundary layer region obtains the desired superconducting transition temperature of 9.1 K ± 0.1 K, almost equivalent to that of high pure Nb bulk material. The optimized CVD reaction method of Nb film with favorable morphology and expected superconductive property at low temperature provided a new strategy and technical process in designing the desired copper-based Nb film SRF cavity.
Opto-electronic properties and solar cell efficiency modelling of Cu2ZnXS4 (X = Sn, Ge, Si) kesterites
Authors: Ratz Thomas , Raty Jean-Yves , Brammertz Guy , Vermang Bart , Nguyen Ngoc Duy 
Published: March 2021

Abstract
In this work, first-principles calculations of Cu2ZnSnS4, Cu2ZnGeS4 and Cu2ZnSiS4 are performed to highlight the impact of the cationic substitution on the structural, electronic and optical properties of kesterite compounds. Direct bandgaps are reported with values of 1.32, 1.89 and 3.06 eV respectively for Cu2ZnSnS4, Cu2ZnGeS4 and Cu2ZnSiS4 and absorption coefficients of the order of 104 cm−1 are obtained, indicating the applicability of these materials as absorber layer for solar cell applications. In the second part of this study, ab initio results are used as input data to model the electrical power conversion efficiency of kesterite-based solar cells. In that perspective, we used an improved version of the Shockley–Queisser model including non-radiative recombination via an external parameter defined as the internal quantum efficiency. Based on predicted optimal absorber layer thicknesses, the variation of the solar cell maximal efficiency is studied as a function of the non-radiative recombination rate. Maximal efficiencies of 25.71%, 19.85% and 3.10% are reported respectively for Cu2ZnSnS4, Cu2ZnGeS4 and Cu2ZnSiS4 for vanishing non-radiative recombination rate. Using an internal quantum efficiency value providing experimentally comparable

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values, cell efficiencies of 15.88%, 14.98% and 2.66% are reported respectively for Cu2ZnSnS4, Cu2ZnGeS4 and Cu2ZnSiS4. We confirm the suitability of Cu2ZnSnS4 in single junction solar cells, with a possible efficiency improvement of nearly 10% enabled through the reduction of the non-radiative recombination rate. In addition, Cu2ZnGeS4 appears to be an interesting candidate as top cell absorber layer for tandem approaches whereas Cu2ZnSiS4 might be interesting for transparent photovoltaic windows.
Theoretical and experimental investigation of chemical mechanical polishing of W–Ni–Fe alloy
Authors: Guo Jiang , Shi Xiaolin , Song Chuanping , Niu Lin , Cui Hailong , Guo Xiaoguang , Tong Zhen , Yu Nan , Jin Zhuji , Kang Renke 
Published: March 2021

Abstract
Fine finishing of tungsten alloy is required to improve the surface quality of molds and precision instruments. Nevertheless, it is difficult to obtain high-quality surfaces as a result of grain boundary steps attributed to differences in properties of two-phase microstructures. This paper presents a theoretical and experimental investigation on chemical mechanical polishing of W–Ni–Fe alloy. The mechanism of the boundary step generation is illustrated and a model of grain boundary step formation is proposed. The mechanism reveals the effects of mechanical and chemical actions in both surface roughness and material removal. The model was verified by the experiments and the results show that appropriately balancing the mechanical and chemical effects restrains the generation of boundary steps and leads to a fine surface quality with a high removal rate by citric acid-based slurry.
Graphene-enabled block copolymer lithography transfer to arbitrary substrates
Authors: Lee Woo-Kyung , Robinson Jeremy T , Whitener Keith E 
Published: March 2021

Abstract
We describe a method for phase separating and transferring block copolymer (BCP) nanoscale patterns to arbitrary substrates for surface-independent nanolithography. The enabling technology is a hydrogenated or oxidized graphene thin film that only weakly adheres to its substrate. BCPs are applied to these graphene-based materials and solvent annealed to effect nanoscale phase separation. Then, taking advantage of the weak interaction of the graphene film and its substrate, the BCP/graphene stack is delaminated easily in water. A target substrate is then used to retrieve the stack, which can then serve as a lithographic mask. The use of water as a lift-off agent allows for chemically mild retrieval of the phase-separated BCP, extending the BCP lithography technique to essentially arbitrary substrates. We demonstrate this graphene-enabled BCP lithography on silicon nitride and polyethylene. We also show that using reduced graphene oxide (RGO) as a thin film enables the transfer of wafer-scale BCP films and lithography on SiOx and Si. We use an RGO support to produce phase-separated BCP solvent-annealed patterns on polystyrene, a result which is not possible using standard BCP solvent annealing and which shows the utility of this technique. Finally, we demonstrate the ability to create nanopatterns of higher complexity by stacking multiple BCP masks, a capability that is not possible using conventional BCP lithography. This technique may have applications in fabricating nanoporous membranes and photonically active coatings.
Art as Political Discourse
Authors: Simoniti Vid 
Published: March 2021

Abstract
Much art is committed to political causes. However, does art contribute something unique to political discourse, or does it merely reflect the insights of political science and political philosophy? Here I argue for indispensability of art to political discourse by building on the debate about artistic cognitivism, the view that art is a source of knowledge. Different artforms, I suggest, make available specific epistemic resources, which allow audiences to overcome epistemic obstacles that obtain in a given ideological situation. My goal is to offer a general model for identifying cognitive advantages for artworks belonging to distinct artforms and genres (e.g. satire, visibility-raising artworks, caricatures, and so on), in a way that can account for each artwork’s historical and cultural specificity. More speculatively, however, my account also comments on the ancient struggle between philosophy and the arts as competing modes of persuasion, and expands our notion of legitimate political discourse to include a greater plurality of discursive genres.
106 A Whole Hospital Delirium Audit with 20 Week Follow-Up
Authors: Khambay E , Katz-Summercorn C , Speed J , Amarnani R , Enfield-Bance A , Mani S , Glasser M 
Published: March 2021

Abstract

Introduction
Delirium is a common manifestation of acute illness, characterised by fluctuating changes in mental state. Its aetiologies and presentations are diverse. This can lead to underdiagnosis. We screened all adult inpatients at Barnet Hospital for delirium. 20 weeks follow-up data was collected, including mortality and admission to institutional care.

Methods
The 4AT and Clinical Frailty Score (CFS) were recorded for every adult inpatient (n = 220) in Barnet Hospital on 13/03/2019. Hospital notes were reviewed to establish whether delirium assessments were performed during admission. Electronic records were used to establish length of stay, discharge destination, mortality and readmission rate over 20 weeks.

Results
30% (n = 65) of inpatients had possible delirium (4AT score ≥ 4). Delirium was more common in older, frailer patients (Table 1). Most patients with delirium were under the care of geriatric (40%) or acute medicine (26%). Only gastroenterology and gynaecology had no patients with delirium. Patients with delirium were 3 times more likely to die during their admission and were twice as likely to be discharged to institutional care (Table 1). 20 week mortality of patients with delirium was 26%.

Conclusion
Delirium is common in hospital inpatients. Delirium has a high morbidity and mortality. Better diagnosis of delirium in hospital may improve outcomes. Table 1: Mean(SD) unless stated. *p &lt; 0.05 Delirium (n = 65) No Delirium (n = 155) Male: % 46 46 Age* 81(11) 71(20) Clinical Frailty Score* 5.6(1.7) 3.8(1.8) Dementia (%)* 53 10 Assisted living: n(%) o Pre-admission * 18.5 3.2 o Post Admission * 44.6 22.6 Length of stay 33 (25) 30.6 (28) Mortality (%) o Hospital * 10.7 3.9 o 20 Weeks * 26.2 14.2 Readmission rate (%) 30.8 31.
137 Specialist Medication Review as Part of the Comprehensive Geriatric Assessment in the Day Hospital Setting
Authors: Bailey L , Brewer L , Carroll J , Seebah S 
Published: March 2021

Abstract

Introduction
Medication use in older people is complex. Consequently, regular medication reviews as an integral part of healthcare provision for older people are necessary. Patients attending consultant-led, multidisciplinary, day hospital clinics have specialist medication reviews undertaken by our senior clinical pharmacist. “Pharmacy Interventions” (PIs) are suggested and typed prior to physician-led patient review.

Method
Data collected by our senior clinical pharmacist were reviewed including patient demographics, clinical characteristics, types of prescribed drugs and PIs. Clinical severity of PIs was assessed using the NCC MERP Medication error index and American Journal Health-Syst Pharm Medication error index. Scores, ranging in clinical severity from A-I (A = capacity to cause error, I = may have contributed to death) and 0–10 (0 = no potential effect, 10 = death) were assigned by the pharmacist and two physicians.

Results
100 patients were included, mean age 82y (range 65-99y). 62% were female and 63% were first time attenders. Mean number of regularly prescribed medications was 7.2 (range 1–16), 10% reported compliance issues. The most commonly prescribed drugs belonged to the “Alimentary tract and metabolism” class (24%), including PPIs, laxatives and blood-glucose lowering medications. 16% and 15% were on regularly prescribed neuroactive and psychoactive medications, respectively. Of suggested PIs, 46% were acted upon during physician review, a further 4% were acknowledged in clinical notes. PIs covered many prescribing issues including drug–drug interactions, incorrect dosing, drug monitoring and administration timing. The average PI scores assigned by the pharmacist, physicians 1 and 2 differed, at 6.4, 3.2 and 4.8, respectively.

Conclusion
PIs suggested at senior pharmacy level are an important component of the comprehensive geriatric assessment, highlighting multiple complex prescribing issues. Clinical severity of PIs was scored lower by physicians, perhaps indicating an underestimation of prescribing errors. Senior pharmacy involvement in the care of frail older outpatients is an invaluable resource.
Association Between Gestational Exposure to Toxicants and Autistic Behaviors Using Bayesian Quantile Regression
Authors: Alampi Joshua D , Lanphear Bruce P , Braun Joseph M , Chen Aimin , Takaro Tim K , Muckle Gina , Arbuckle Tye E , McCandless Lawrence C 
Published: March 2021

Abstract
Autism spectrum disorder, which is characterized by impaired social communication and stereotypic behaviors, affects 1%–2% of children. Although prenatal exposure to toxicants has been associated with autistic behaviors, most studies have been focused on shifts in mean behavior scores. We used Bayesian quantile regression to assess the associations between log2-transformed toxicant concentrations and autistic behaviors across the distribution of behaviors. We used data from the Maternal–Infant Research on Environmental Chemicals study, a pan-Canadian cohort (2008–2011). We measured metal, pesticide, polychlorinated biphenyl, phthalate, bisphenol-A, and triclosan concentrations in blood or urine samples collected during the first trimester of pregnancy. Using the Social Responsiveness Scale (SRS), in which higher scores denote more autistic-like behaviors, autistic behaviors were assessed in 478 children aged 3–4 years old. Lead, cadmium, and most phthalate metabolites were associated with mild increases in SRS scores at the 90th percentile of the SRS distribution. Manganese and some pesticides were associated with mild decreases in SRS scores at the 90th percentile of the SRS distribution. We identified several monotonic trends in which associations increased in magnitude from the bottom to the top of the SRS distribution. These results suggest that quantile regression can reveal nuanced relationships and, thus, should be more widely used by epidemiologists.