bluuebunny/crossref_metadata_2025 huggingface dataset:
Hemocompatibility study of surface-attached antibiofouling polymer monolayers
Authors: Pidhatika Bidhari
Published: August 2019

The interface between biomaterials and body fluid such as blood is a critical concern, because biomaterial-centered protein fouling and infection adversely affects the quality of life of many patients and cause major health care costs. Our research focused on polymer functionalization on surfaces to create antibiofouling interfaces (i.e. interfaces that repel the adhesion of proteins and microorganisms) in biomaterial-related applications, such as surgical instruments and blood-contacting biomedical devices. To this end, we have studied two hydrophilic polymers, namely poly(2-oxazoline) and poly(ethylene glycol), attached on metal oxide surfaces in brush configuration through a polyelectrolyte surface anchor, poly(L-lysine). Apart from antibiofouling properties, blood-contacting surfaces must also serve hemocompatibility. Here the hemocompatibility of antibiofouling monolayer on silicon oxide surfaces prepared from either poly(2-oxazoline) or poly(ethylene glycol) grafted on a main backbone poly(L-lysine), has been studied. The activation of C5a (complement system), TAT and kallikrein (coagulation cascade), PF4 and sP-selectin, (platelet activation) after incubation of the polymer-modified surfaces in whole blood was measured by means of ELISA kit. The results showed that in general, the contact between blood and polymer monolayer activated the complement system, but relatively did not activate the coagulation cascade and the platelet surface marker.
Physical properties analysis of the liquid produced by polystyrene pyrolysis
Authors: Selpiana  , Santoso Budi , Pramayuda Dede , Ismoro Damar Setyo
Published: August 2019

The higher consumption of plastic causes environmental problems. This study was aimed at recycling plastic wastes by using a pyrolysis process with the variables were the ratio of polystyrene mixture and heating rate. The types of polystyrene were used namely, oriented polystyrene (OPS), expanded polystyrene (EPS) and high impact polystyrene (HIPS). Ratios of raw material mixture (OPS: EPS: HIPS) of 1: 0: 0, 0: 1: 0, 0: 0: 1, 2: 1: 1, 1: 2: 1, 1: 1: 2, 1: 1 : 1. Heating rate variations were 2 °C/min, 4 °C/min, 6 °C/min, 8 °C/min and 10 °C/min. The analysis was conducted to the physical properties of liquid produced by pyrolysis, namely heating value, kinematic viscosity, density, and flash point. The heating value tended to increase with the increase of heating rate, the highest heating value was obtained at a ratio of a mixture of 2: 1: 1. The lowest kinematic viscosity value was at the ratio of a mixture of 1: 2: 1 and 1: 1: 1. Density fluctuated but tended to increase with the increase of heating rate. Flashpoint of the entire sample was below 32.6 °C. The ratio of a raw material mixture and heating rate affected the content of the compound of the liquid fuel produced. These compounds had different physical properties. The difference of physical property of each compound of the liquid fuel would affect the physical properties of the liquid produced by pyrolysis.
No antimalarial resistance of Plasmodium falciparum varian West Indonesia using molecular markers screening
Authors: Ghiffari Ahmad , Rahman Rahman , Anwar Chairil
Published: August 2019

Artemisin-based combination therapy (ACT) were widely used in Indonesia for the treatment of Malaria Plasmodium falciparum. Previous study in East Indonesia, located in Irian showed no prevalence of resistance, suggesting the treatment still effective in the area. This study aimed to provide baseline data of antimalarial drug resistance markers on P. falciparum isolates in Lampung West Indonesia. Mutation on genes associated with ACT (PfRBP9) were assessed by PCR amplification. Mutation on the marker related with artemisin resistance were determined by DNA sequencing technique. Isolates of 14 samples revealed no mutation in the D56V codon which is usually confined. This study has demonstrated a low prevalence resistance allele in the study area. Continuous surveillance of antimalarial drug efficacy is recommended and the findings provide information for stakeholders ensuring proper policy controlling malaria.
Effect of impregnation methods and bioresin concentration on physical and mechanical properties of soft-inner part of oil palm trunk
Authors: Hartono R , Erwinsyah  , Hidayat W , Damayanti R
Published: August 2019

Bioresin from derived of pine (Pinus merkusii) was used to increase the strength of the soft-inner part of oil palm trunk (S-OPT). This purpose of this study was to evaluate the effect of impregnation methods (soaking 1 day, 3 days, and vacuum 600 mmHg for 1 hour) and bioresin concentration (0%, 5%, 10%, 15%, and 20%) on the physical and mechanical properties of S-OPT. Bioresin was dissolved with ethanol. The result showed that weight gain from bioresin into S-OPT was 0.85 % - 39.4%. The bioresin impregnation with several concentration significantly improved the physical and mechanical properties of S-OPT up to (1) 5.7-57.14% in density; (2) 29.94%-145.18% in compressive strength; (3) 114.78%-345.66% in modulus of elasticity (MOE); and (4) 43.01%-111.79% in the in modulus of rupture (MOR). The best performance of S-OPT when bioresin impregnated 20% bioresin using vacuum method as shown higher the physical and mechanical properties.
Synthesis of chitosan/alumina composite by sol gel method for adsorption of procion blue MX-R dye from wastewater songket industry
Authors: Fatma  , Yuliasari Nova , Riyanti Fahma , Hariani Poedji Loekitowati , Nurbaiti Barisah
Published: August 2019

Research about the synthesis of chitosan/alumina composite using the sol-gel method and its application to removal procion blue MX-R dye had been conducted. The synthesized chitosan/alumina composite was characterized using FTIR to determine functional group, SEM-EDS to find out the surface morphology and elements composition of chitosan/alumina composite. The pHPZC is used to determine the appropriate pH condition on the adsorption process of chitosan and chitosan/alumina composite on procion blue dye solution. The FTIR spectra of chitosan represent the functional groups O-H, N-H, C-H and C-O while the chitosan/alumina composite is the addition of functional group of Al-O. The morphology of chitosan/alumina composite analysis by SEM showed that is heterogenous and porous. The EDX analysis showed that the present Al element of 5.49 % in the composite which indicates that synthesis of composite has been successful. Chitosan and composite have different pH pzc where chitosan at pH 6.02 and composite at pH 7.26. The optimum condition adsorption of procion blue MX-R using chitosan obtained at an initial concentration of 180 mg/L and contact time of 60 minutes, while the chitosan/alumina composite obtained at an initial concentration of 160 mg/L and 50 minutes contact time. The isotherm model that is suitable for describing the adsorption process is Freundlich isotherm for both adsorbents. The composite has the effectiveness of adsorption on procion blue MX-R from wastewater songket industry greater than chitosan ie 85.696 and 60.829 %, respectively.
The conversion of expanded polystyrene waste to liquid fuel using Cu-Al2O3 by the thermal catalytic cracking process
Authors: Selpiana  , Santoso Budi , Suprapto Debi Putri , Patratama Ridho , Pramayuda Dede
Published: August 2019

The high use of plastic and the length of time the decomposition will worsen environmental conditions. The processing of plastic waste by incineration was not a safe method for the environment because it will produce gas emissions that potentially become pollutants. The catalytic cracking process is one of the ways to process polystyrene plastic waste into liquid fuel. The purpose of this study is to identify the effect of cracking temperature and mass of catalyst towards the volume and fuel quality of the production. The research conducted through the thermal catalytic cracking process. The mass of catalyst Cu-Al2O3 is 0.5 g, 1 g, 1.5 g. The cracking temperature is 150 °C, 200 °C, 250 °C. Cracking time is 90 minutes. The highest volume of the liquid fuel was 113 mL at a 250°C cracking temperature and the addition of 1g catalyst. The results of the best density analysis obtained at 0.74 g/mL, and the octane number of RON is 100, MON is 90, and AKI is 94.4.
Nanoparticulate formulatiom of christmas palm seed (Adonidia merrillii) ethanolic extract containing lactic acid for antidiarrheal therapy
Authors: Mardiyanto  , Sandi Sofia , Herlina  , Kurniawan Ivan
Published: August 2019

Preparation of Christmas Palm seeds ethanolic extract and lactic acid loaded nanoparticles aims to obtain an antidiarrheal (caused by Escherichia coli) therapy by using nano herbal. Preparation of the nanoparticles was done by ionic gelation method. There were three formulas (F) which had been evaluated in this study based on the difference amount of Ca(OH)2, 12.5 mg for F1, 17.5 mg for F2, and 22.5 mg for F3. All formulas revealed an entrapment efficiency percentage of 75.489 over or less 0.563 (F1); 76.885 over or less 0.046 (F2); and 74.844 over or less 0.724% (F3). The second formula (F2) produced the highest %EE therefore it was distinguished as the optimum formula. The results of nanoparticles characterization of an optimum formula such as average diameter, poly dispersity index (PDI), and zeta potential using particle size analyzer were 1230.1 nm; 0.482; dan 27.5 mV respectively. An in-vivo antidiarrheal evaluation on rats using an optimum formula containing 1 gram of extract showed that nanoparticles possed an equal antidiarrheal effect to intraperitoneal gentamicin sulfate 8 mg/kg body weight with diarrhea inhibitory of 71.539%.
Effectiveness of Ethanolic Extract Ketepeng cina Leaves (Senna alata L.) As Antidiabetic Activity Test In Male Wistar Rats Induced by Alloxan
Authors: Herlina  , Amriani Annisa , Solihah Indah , Damayanti Putri , Rais Sri Wahyuningsih
Published: August 2019

Antidiabetic activity test of ethanolic extract of ketepeng cina leaves (Senna alata L.) to rats induced by alloxan has been done. Male wistar albino rats weree used as animal models which divided into 6 groups, normal group (aquadest), negative control group (Sodium CMC 0,5%), positive control group (insulin by 1IU/kgBW), and 3 test group (ethanolic extract of ketepeng cina leaves 200, 400, dan 800 mg/kgBB). Rats blood glucose level after induced intraperitoneally by alloxan 130 mg/kgBB can be stated as diabetic when >200 mg/dL. Antidiabetic-activity was tested by measuring on blood sugar levels by using the DTN-410-K fotometer, on day 0, 5, 10, and 15. The result of AUC0-15 and percentage of decreasing blood sugar levels for positive control group are 2557,35 and 51,20%, and 3 treatment groups (200 mg/kgBW, 400 mg/kgBW, and 400 mg/kgBW) 2745,6 and 39,94%; 2618,55 and 47,54%; 2448,425 and 57,72%. This point indicated that the ethanolic extract of ketepeng cina leaves has an antidiabetic activity and there is no significant difference compared with insulin (p<0,05). 800 mg/kgBW dose is the effectivity dose from other treatment doses, because it had the lowest AUC0-15 and the highest perscentage of decreasing blood sugar levels. According to the relation between percentage of blood glucose decrease level with dose, value of ED50 of ethanolic extract of ketepeng cina leaves is 522.413 mg/kgBW.
Landcover change analysis of besitang watershed, Langkat-North Sumatera
Authors: Zaitunah Anita , Samsuri  , Putri Amaliyah
Published: August 2019

Watershed is an ecosystem area bordered by topographic pattern and serves as serves as a collector, storage and distributor of water, sediments, pollutants and nutrients in the river system and throughout by a single outlet. The high of population growth led to greater land use change. This research aimed to identify land cover classes and land cover change in Besitang watershed between 1990, 2005 and 2015. This research used Landsat 5 imagery in 1990 and 2005, and Landsat 8 imagery in 2015 with supervised classification using method maximum likelihood classifier. The result showed that there were 12 classes of land cover in the Besitang watershed, they were primary forest, secondary forest, mangrove forest, scrub, rubber plantations, oil palm plantations, dry land agriculture, bare land, settlement, fishpond and water body. The largest area of land cover area is primary forest covering an area of 38,542.43 hectares (39.94%) in 1990, 34,279.16 hectares (35.52%) in 2005, and 34,620.41 hectares (35.88%) in 2015. The largest area of land cover change between 1990 until 2005 is mangrove forest to fishpond with covering an area of 2,364.21 hectares change. While the largest area of land cover change between 2005 until 2015 is mangrove forest to oil palm plantation with covering an area of 1,016.82 hectares changes.
Inventory of wildlife in the protected forest area Bukit Jambul Gunung Patah as basic data to support sustainable management
Authors: Setiawan D , Patriono E , Marisa H , Setiawan A , Yustian I , Pragustiandi  , Iqbal M
Published: August 2019

Bukit Jambul Gunung Patah protected forests is located at the Sumatran submontane and montane rainforest ecosystem region, South Sumatra. Various activities that exist around the area of protected forests can caused disruption of the existence and diversity of animals that inhabit the area. Therefore, a wildlife inventory survey is needed, particularly focus on mammals and birds taxa, because two taxa have clear data information in the region. This research has been carried out from April to July 2018 with the exploration methods, The results of the study found 34 species of birds, and 11 species of mammals,. Based on the Government Protection Regulation of the Republic of Indonesia No.P.20/MENLHK/Setjeb/Kum.1/6/2018 was found 12 species protected, 6 threatened species based on IUCN redlist, and 5 species into Appendinces I based on CITES. From the results and compared with the study database of endangered species at Rantau Dedap by the Indonesian Greencap Team in 2014-2015, 12 species mammals were found 9 of which were threatened species, By comparison of baseline data and with species found that are in the category of threatened status. There was decreased in the threatened and protected species found this indicates that the habitat has begun to be disturbed. So that, a long-term study is needed to providing comprehensive biodiversity information to support the management of the protected forest Bukit Jambul Gunung Patah to remain sustainable.
Air-Sea interaction in the Tropical Pacific Ocean during 2018 as revealed by multi-satellite data
Authors: Antakusuma Willy , Nur Muhamad , Iskandar Iskhaq
Published: August 2019

The air-sea interaction in the tropical pacific ocean is a critical to influence climate change around Pacific Ocean and whole of the world. According to that matter, this research is supposed to explain the variations of climate parameters in Pacific Ocean during 2017/2018 as La Niña tendency with using saveral satellite data which consist of: sea surface temperature (SST), sea level pressure (SLP), outgoing longwave radiation (OLR), wind and precipitation with length of time from 2005 until 2018 as compared with climate activity in 2010/2011 La Niña phenomenon. The 3.4 nino index showed there is short periods (less than six month) negative values deviation in 2017/2018 or cannot be claimed as La Niña phenomenon. Consistent with 3.4 nino index, the air-sea interaction in 2017/2018 has showed normal condition since no significant anomaly activity in parameters used if compared with parameters activity in 2010/2011 La Niña phenomenon.
Measurement and analysis of TS-Frequency relationship on mackerel tuna (Euthynnus affinis) using bandwidth frequency
Authors: Jaya I , Aulya R , Fauziyah
Published: August 2019

Mackerel tuna (Euthynnus affinis) is a pelagic fish from Scombridae family and one of the commercially important species. The fish is mostly found in the water column from the surface down to about 50 m. Mackerel tuna spread widely in the tropical and subtropical waters, including the Indian Ocean, Pacific, Mediterranean Sea, and Black Sea. Since the level of exploitation of this fish resource is relatively high, it is critical to have an accurate assessment on the status of the stock. In this paper we report and discuss the measurement results of the acoustic target strength (TS) of Mackerel tuna using acoustic broadband technique. A broadband technique was used to better characterized the basic TS-Frequency relationship of the target, and hence less bias in biomass estimation. Target Strength measurement was performed using SIMRAD EK-80 scientific acoustic instrument with frequency bandwidth 160-240 kHz and sound pulse was transmitted to the target with 1 CW pulse and 8 FM pulse. The fish was tethered and positioned directly below the acoustic transducer. The results of the measurements are presented in terms of TS-Frequency. It is found that the TS-F relationship fluctuates, where the highest TS value -54.64 ± 4.64 dB is in 190-200 kHz frequency interval.
Biological response to quails (Coturnix coturnix) given hydrolyzed feather meal at different levels
Authors: Said M I , Abustam E , Pakiding W , Mide M Z
Published: August 2019

The biological response is one of the important parameters to evaluate the performance of a farm. Each individual will give a different biological response according to the treatment applied. Feeding is one of the biological needs of the quail (Coturnix coturnix). The purpose of this study was to evaluate the biological response of quails to the treatment of hydrolyzed feather meal with different levels. A total of 100 heads quail, one week old were used as samples. The treatment consisted of four levels (L0 = 0%, L1 = 1%, L2 = 1.5% and L3 = 2%). Each treatment was repeated five times. The treatment was uses a unidirectional design of completely randomized design (CRD) a 4x5 = 20 treatment units. Each treatment unit was uses five heads quails. The duration of the observation process was 30 days. The data were analyzed statistically using ANOVA. The results showed that the treatment of hydrolyzed feather meal at different levels at a level of 2% did not had a significant effect (P>0.05) on all parameters. The biological response of the increase in body weight gain was in the range of 2.00-2.37 g/head/day. The highest body weight in the treatment with L3 (2%), in weeks 3 and 4. The average intake of feed was 14.84-15.79 g/head/day, the feed conversion was 0.60-0.68 and the in vivo digestibility of the protein was 40.48-51.69%. The results of the study indicate that the introduction of broiler feather meal from the hydrolysis in the quail feed (Coturnix coturnix) at a level of 2% has the same biological response. Therefore, an introduction with a level of >2% should be applied to discover the differences between treatments.
The dynamics of functional microbes population in two depths under raru (Cotylelobium spp) stand
Authors: Elfiati D , Susilowati A , Modes C
Published: August 2019

Raru (Cotylelobium spp) is one of the endemic plants in North Sumatra from the Dipterocarpaceae family. Plant growth is strongly influenced by the condition of the soil environment. Soil provides nutrients to increase plant growth. Soil also a habitat for various microbes that affect plant growth. This study aimed to calculate functional microbial populations under raru stands such as arbuscular mycorrhizal fungi, phosphate solubilizing microbes, and cellulose decomposer microbes. The measurement of the population use plate count methods. Soil samples were taken in composite with 0-5 cm and 5-20 cm in the raru pulut, raru dahanon and raru songal rhizosphere area in Bona Lumban Village, Tukka District, Central Tapanuli Regency North Sumatra. The result showed that a functional microbial population was calculated higher at a depth of 0-5 cm compared to a depth of 5-20 cm. The microbial population of phosphate solubilizing microbes ranged from 10.12x 103 to 92.44x103 CFU mL−1 with the largest population found in the raru songal rhizosphere. Cellulose decomposer microbial populations ranged from 6.21x103 to 21.55x103 CFU mL-1 with the highest population found in the raru pulut rhizosphere. The highest arbuscular mycorrhizal fungi density in raru dahanon rhizosphere.
Microplastics Dissemination from Fish Mugil dussumieri and Mangrove Water of Muara Teluknaga, Tangerang, Banten
Authors: Rahmawati Nur H F , Patria Mufti P
Published: August 2019

Plastic trash accumulation under 5 mm (microplastics) has been playing as water contaminant for a long time period. Microplastics dissemination in the ocean can be threat and trigger for biological effects especially if ingested by the marine biota. The fish Mugil dussumieri is marine biota which is marine biota food resource used as bioindicator to investigate the presence of microplastics in Mangrove Muara Teluknaga, Tangerang, Banten. Microplastic are found both from fish Mugil dussumieri sample and the water sample during the investigation. The type of microplastics most commonly found on M. dussumieri sample and water sample is fiber. The average fiber can be found digestive organ is 164 particles/organs more than respiratory organ 132.5 particles/organ. The average amount of fiber found is 431.5 particles/L and film is 291.5 particles/L.
A numerical study of mixing and sediment transport caused by tidal in the Bontang waters
Authors: Alghifari N , Nasution Y N , Mandang I
Published: August 2019

Freshwater and sediment that carried by the river then flow into the bay will cause sediment transport and mixing in the bay, in this case the Bontang Waters. The three-dimensional finite difference baroclinic model system (ECOMSED) is used to do numerical studies of the mixing and sediment transport process, this model was simulated for 40 days and verified using tidal data that taken using CTD. The values of sediment concentration ranged from 1×10−6 to 1×10−5 gr/cm3 on the surface, with sediment transport ranging between 0 – 12 (gr/m2)/s. Salinity on the surface is 0 - 35 ppm, and the temperature is 25 - 40 ° C. Mixing occurred at one river mouth with a salinity profile of 25 ppm on the surface and 32 ppm at the bottom, the sediment concentration value was in the range of 1.2×10−5 gr/cm3 on the surface and decreased to 4×10−6 gr/cm3 at the bottom.
Providing biodiversity information to support sustainable development of Sugihan wetlands, South Sumatra
Authors: Setiawan Arum , Iqbal Muhammad , Setiawan Doni , Yustian Indra
Published: August 2019

Air Sugihan or Sugihan wetlands is a subdistrict in Ogan Komering Ilir district, South Sumatra province, Indonesia. The area covering is about 2.593 km2, mostly dominated by wetlands, ranging from peatland to the mangrove zone. The Padang-Sugihan Wildlife Reserve is a Wildlife Sanctuary that borderly or within Air Sugihan wetlands. Before the area was set aside for a wetland reserve in April 1983 the area was being prepared for transmigrant settlers. Among other threatened wildlife, birds and fishes are two taxa that very fragile to human disturbances. Since November 2016, we explore basic biodiversity information of Sugihan wetlands, particularly focus on fish and bird diversity. A total of 33 species of fishes and 39 birds were recorded, suggest the wetlands in this area support important habitat of rich diversity. To collect information on bird diversity, three survey methods were applied (riverine survey, time point counts and incidental search). For collecting data of fishes, we collect specimens from local fishermen, with additional data collected by us using hand netting and fish trap netting. Long-term study was initiate to providing comprehensive biodiversity information to support sustainable development of Sugihan wetlands.
Ab initio calculations of p-shell nuclei up to N2LO in chiral Effective Field Theory
Authors: Maris Pieter
Published: August 2019

Nuclear structure and reaction theory are undergoing a major renaissance with advances in many-body methods, realistic interactions with greatly improved links to Quantum Chromodynamics, the advent of high performance computing, and improved computational algorithms. State-of-the-art two- and three-nucleon interactions obtained from chiral Effective Field Theory provide a theoretical foundation for nuclear theory with controlled approximations. With highly efficient numerical codes, tuned to the current generation of supercomputers, we can perform ab-initio nuclear structure calculations for a range of nuclei to a remarkable level of numerical accuracy, with quantifiable numerical uncertainties. Here we present an overview of recent results for No-Core Configuration Interaction calculations of p-shell nuclei using these chiral interactions up to next-to-next-to-leading order, including three-body forces. We show the dependence of the ground state energies on the chiral order; we also present excitation spectra for selected nuclei and compare the results with experimental data.
The Bethe-Salpeter approach to bound states: from Euclidean to Minkowski space
Authors: Castro A , Ydrefors E , de Paula W , Frederico T , de Alvarenga Nogueira J H , Maris P
Published: August 2019

The challenge to obtain from the Euclidean Bethe–Salpeter amplitude the amplitude in Minkowski is solved by resorting to un-Wick rotating the Euclidean homogeneous integral equation. The results obtained with this new practical method for the amputated Bethe–Salpeter amplitude for a two-boson bound state reveals a rich analytic structure of this amplitude, which can be traced back to the Minkowski space Bethe–Salpeter equation using the Nakanishi integral representation. The method can be extended to small rotation angles bringing the Euclidean solution closer to the Minkowski one and could allow in principle the extraction of the longitudinal parton density functions and momentum distribution amplitude, for example.
Fusion barrier distribution and superheavy elements
Authors: Hagino K , Tanaka T
Published: August 2019

The barrier distribution, originated from channel coupling effects in heavy-ion fusion reactions, has been extracted experimentally for many systems using either a fusion excitation function or an excitation function of large-angle quasi-elastic scattering. In this article, we discuss an application of the latter method to the 48Ca+248 Cm system, which is relevant to hot fusion reactions to synthesize superheavy elements. To this end, we carry out coupled-channels calculations for this system, taking into account the deformation of the target nucleus, and discuss the role of deformation in a formation of evaporation residues.
Investigation of ions in human whole saliva by analytic techniques
Authors: Miura V M , Zamboni C B , Tasso O G , Lewgoy H R , Jesus K A , Silva R Y R
Published: August 2019

In this study, ions of clinical relevance in non-stimulated human whole saliva obtained from healthy subject’s donors (adults and children) at São Paulo city (Brazil), were investigated. The Instrument Neutron Activation Analysis (INAA) and Energy Dispersive X-Ray Fluorescence (EDXRF) techniques were used. The comparison concentration between adults and children for Cl, K, Ca and Fe showed significant differences for all elements, emphasizing the need of adopting different reference values.
The influence of superfluid core cooling in the braking index of Pulsars.
Authors: Frajuca C , Bortoli F S , Santos G A , Nakamoto F Y , Souza M A
Published: August 2019

Pulsars are stars from which electromagnetic radiation is observed to pulsate in well-defined time intervals as the star rotates and the emission of eletromagnetic signal is located in a place different from the rotation center. The frequencies of the pulses decay with time, quantified by the braking index (n). In the canonical model n = 3, in general, for all pulsars, but observational data shows that n is lower than 3. In this work a new model is presented, based on a modification of the canonical one incorporating the influence of neutron and proton density that appear in the superfluid core and, as the star cools down, the density of the superfluid core increases making the star to shrink with time and temperature, making the inertia moment to decrease. The difference ot this model from the canonical one is that the star moment of inertia decreases with time (what would accelerate the rotation of the star) what makes the star to not slow down as fast as it should without this process.
Spin-orbit effects in the 8Li+58Ni elastic scattering
Authors: Santos O C B , Lichtenthäler R , Pires K C C , Moro A M , Umbelino U , Zevallos E O N , Assunção M , Appannababu S , Alcántara-Núñez J , de Lara A L , Scarduelli V , Guimarães V , Lépine-Szily A , Serra A. S. , Linares R , Zagatto V A B , de Faria P N , Morcelle V , Morais M C , Barioni A , Shorto J M B
Published: August 2019

In this work we present an elastic scattering angular distribution for the 8Li+58Ni system measured at Elab = 26.1 MeV. The 8Li beam was produced in the Radioactive Ion Beams in Brasil (RIBRAS) facility using the 7Li primary beam delivered by the 8-UD Pelletron accelerator. The angular distribution covers the angular range from 20 to 85 degrees in the center of mass frame. The data have been analysed by optical model and coupled channels calculations, including couplings to low-lying states in 8Li and the spin-orbit interaction. Our results indicate that the inclusion of the spin-orbit interaction in the calculations is important to describe the data at backward angles.
Standard Reference for Zero Temperature from Quantum Supersymmetry is Possible?
Authors: Marques C , Dias G S , Chavez Sanchez H H
Published: August 2019

Supersymmetry at a susy harmonic oscillator, H(ω
1, ω
1), can be broken or restored in certain conditions and parameters, that are linked with thermal interaction and with a polynomial interactions of creation and annihilation operators. All possibles supersymmetric harmonic oscillators represented by a point (ω
1, ω
1) in the frequency space of the system, are in a two dimensional surface parametrized by the (ω
2, α
2), which we call s-surface, where α
2 is the interaction parameter. The temperature in the s-surface are intended to be zero. Interaction with the thermal bath represented by the tilde Hilbert space from the doubling Hilbert space, establishes thermal oscillations that push the system from the s-surface. In such a way we can define the set of all supersymmetric harmonic oscillator or in a equivalent way the s-surface as a global standard reference for zero temperature.
Two-way coupled simulation of the Francis-99 hydrofoil using model order reduction
Authors: Tengs Erik , Einzinger Johannes , Storli Pål-Tore
Published: August 2019

The Francis-99 hydrofoil is simulated using a quasi two-way Fluid-Structure Interaction procedure. The structural domain is reduced by the use of modal decomposition, and solved for inside the commercial fluid solver ANSYS CFX. Both the first order Backward Euler and second order Crank-Nicolson time discretization scheme is used in the structural equations, with significantly different results. Several coupled fluid-structure phenomena is observed that would be unobtainable in a normal one-way approach. The most interesting is an “added stiffness” effect, where the eigenfrequency of the foil increases when the flow velocity is increased. This trend corresponds well with available experimental results. The same phenomenon is observed in the hydrodynamic damping on the foil. Self-induced vibration due to vortex shedding is also simulated with good results.

The implemented two-way approach allows the different forcing terms to be tracked individually, due to the discretization of the second order structural system. This provides insight into the underlying physics behind the different FSI phenomena seen, and helps us explain why the damping and eigenfrequency characteristics change as the flow velocity passes the lock-in region.
A test of the v2-f k-ϵ turbulence model for the prediction of vortex shedding in the Francis-99 hydrofoil test case
Authors: Sagmo K F , Storli P T
Published: August 2019

A test of the v
2 − f k − ϵ turbulence model for the flow around the Francis-99 hydrofoil geometry is conducted in order to assess it’s accuracy of trailing edge vortex shedding prediction. The model is based on the k − ϵ turbulence model, but needs no wall damping function, and also allows near-wall turbulence anisotropy. For reference, the model results are compared with the the SST k − w, in addition to preliminary experimental results previously published. It is indicated that the v
2 − f k − ϵ model gives at least as good, or better results than the more commonly used SST k − w model for the present case, though further measurements are needed in order to make a proper conclusion.
Fluid structure interaction of Francis-99 turbine and experimental validation
Authors: Østby Petter T. K. , Agnalt Einar , Haugen Bjørn , Tore Billdal Jan , Gunnar Dahlhaug Ole
Published: August 2019

The ability to predict a francis runners dynamic response to the exciting forces is paramount to avoid unwanted disintegration of the turbines components. In this article, each of the principal factors contributing to the dynamic response of the runner; eigenfrequency, mode shape, damping and pressure force, is individually examined and compared to the measured values from the Francis-99 runner. Even though the runner is made with a bolted connection between the blades and crown/band, and thus severely increasing the complexity, quite accurate predictions are possible using methods previously validated for massive and symmetric runners. All calculations are conducted on the best efficiency point and with eigenmodes corresponding to Nodal Diameter 4 as excited by the second harmonic of the guide vane passing frequency. The calculated natural frequency for the first two ND4 eigenmodes are within ±5% of the measured values. Further are the calculated eigenmodes, forcing pressure field and hydrodynamic damping all within measurement tolerances with some minor exceptions.
Application of the Harmonic Balance method for regime change prediction using Francis-99 test case
Authors: Cvijetić Gregor , Čulić Luka , Jasak Hrvoje
Published: August 2019

An efficient method for predicting the turbine start-up and shut-down flow parameters is presented in this paper. Due to start-up or shut-down usually lasting a large number of periods, simulations of such processes are highly demanding and long lasting. To alleviate this, a modified Harmonic Balance method is used, thus casting a problem into spectral space and solving start-up and shut-down simultaneously, as a complete period. By doing this, the results are obtained in a fraction of time required by time-accurate simulation. Furthermore, the same approach could be used for any change of regime from operating point OP1 to operating point OP2 and back to OP1. The method is implemented in foam-extend and suitable for solving incompressible turbulent Navier–Stokes equations. Validation is performed on two test cases: a simple 2D pump case for initial validation, followed by a Francis turbine. Francis turbine test case and experimental data are provided by the Francis-99 Workshop. For Francis turbine the power curve is assembled and compared with experiment.
Reliability study of U-type multistage interconnection networks
Authors: Stergiou E , Liarokapis D , Glavas E , Angelis C , Margariti S V
Published: August 2019

Multistage Interconnection Networks (MINs) are used in wide applications of multiprocessor systems in order to set up connections between various nodes such as processors and memory modules. Reliability can be considered as one of the most challenging issues in these systems because this can degrade or cancel the network performance and consequently the effort of the whole system. Here, a type of multistage fabric called U-type is selected for study, particularly in terms of its reliability. This fabric turns out to be the most appropriate type for constructing parallel systems due to the particular features that it possesses. This study reveals that U-type fabrics are ideal devices as they present mostly high values of reliability and low values of latency compared to unidirectional fabrics. This behaviour becomes more intensive when it is used in a cluster that demands service that includes a high percentage of “local type traffic.” Thus, U-type multistage devices can considerably enhance the connection points in constructing parallel systems, improving internal data flows.
Structural Reliability of Dapped End Beams with Different Reinforcement Layouts under Dynamic Loading
Authors: Syed Z I , Kewalramani M , Hejah E S
Published: August 2019

Reinforced concrete Dapped End Beams (DEB), also known as half-joints, are used in bridges and many other pre-cast constructions to reduce end depth and increase lateral stability. Dapped end beams are expected to experience dynamic loads when used in bridges, the available past studies on the behavior and damage assessment of DEBs are mainly for static loading. The reinforcement layouts of DEBs can influence the behavior of these shear critical members under impact loading. Better understanding of the crack propagation and failure patter of DEBs under dynamics loads is required for safe and economic design of these structural elements. A non-linear numerical transient study was conducted to investigate the dynamic performance of DEBs with different reinforcement layouts. Advanced material models capable of including strain-rate effect and material non-linearity to capture realistic behavior of DEBs were used. The simulated models in finite element package LS-DYNA were verified and used to conduct detailed parametric study to investigate the impact behavior of DEBs with different reinforcement layouts. Sensitivity of concrete compressive strength, main dapped end reinforcement and special shear reinforcement detailing on the structural reliability of DEBs were studied.
Preparation and Properties of SiC Porous Ceramics with Double-Particle Size
Authors: Xu Chengshi , Dong Youming , Liu Yang , Li Huan , Deng Xiangyun
Published: August 2019

In this paper mixed two kinds of SiC particles with different diameter (50-70 mesh and 80-90 mesh) as aggregate of SiC porous ceramics. And the porous ceramic properties were measured when the pore-making agent was 7.5wt%, 10wt% and 15wt% respectively. The experiments show that the porosity, flexural strength and filtration pressure drop of double-particle size porous ceramics is optimized compared with single size porous ceramics. In the pore-forming agent was 10wt% and 50-70 mesh SiC particle was 10wt%, the flexural strength was 40.71MPa, and porosity was 35.69%. It was 4.76MPa and 6.9% higher than single-particle size sample, and the filtration pressure drop has a significant decrease.
The Use of Waste Glass for Cement Production
Authors: Halbiniak J , Major M
Published: August 2019

The vast body of research conducted so far has focused on the use of waste glass as a partial replacement for cement or aggregate in the production of materials with cement matrix. This paper presents an alternative method of using glass waste for cement production. Grinding of previously burnt Portland clinker with glass cullet in green and white colours was used. The glass cullet was ground with Portland clinker in proportions of: 92.5% clinker and 7.5% green and white glass, 85% clinker and 15% green and white glass. Furthermore, pure cement was mixed with green and white glass fragmented in the disintegrator with the same proportions. This allowed for obtaining 8 series of cements (4 series with green glass and 4 series with white glass) and pure cement without waste glass. The compressive strength tests conducted after 2, 7 and 28 days made it possible to analyse the effect of the quantity and colour of waste glass and the method of its application (grinding with Portland clinker, mixing glass with pure cement) on the mechanical parameters of standard mortars. The highest mean compressive strength values after 2, 7 and 28 days were obtained for mortars made of cement coming from grinding of Portland clinker with 15% white glass. Furthermore, the following examinations were conducted: the beginning of the setting time and the degree of grinding of cements.
Toughening Mechanism and Application Analysis of ZrO2 Ceramics under High Speed Strain Condition
Authors: Zhang Lingfeng , Sun Dong , Xiong Yi , Liu Yuliang
Published: August 2019

In order to study the impact properties of ZrO2 ceramics and analyze the failure characteristics to improve the brittleness of ZrO2 ceramics, we used a high-power glass pulsed laser to test the impact of ZrO2 ceramics. Observing the fracture morphology by scanning electron microscopy, we found that the failure of ceramics is mainly caused by spallation. The cracked surface is dominated by typical brittle fractures, and there are more crystals appearing and cracking. The surface does not expand along a single plane, but forms a large number of steps. The direction of the crack and the density distribution indicate that the failure is caused by the reflected tensile wave. At the same time, the surface layer of the material generates a dense compression layer of about several tens of micrometers due to compressive stress, and no cracking occurs in the compression layer. This mechanism indicates that ZrO2 ceramic materials with surface strengthening and matrix toughening can be formed under suitable laser energy.
Spreading and Wetting Behaviors of Sn2.5Ag0.7Cu0.1RE0.05Ni Solder on the Surface of Cu Substrate under Ultrasonic Vibration
Authors: Yin Chenxiang , Zhang Keke , Li Shijie , Li Junheng
Published: August 2019

The spreading and wetting behaviors of Sn2.5Ag0.7Cu0.1RE0.05Ni lead-free solder on the surface of Cu substrate under ultrasonic vibration were studied by SEM, EDS and other methods. The ultrasonic time was 1, 2, 3, 4, 5 s, respectively and was compared with the spreading of solder in the condition of soldering flux. The results showed that the Sn2.5Ag0.7Cu0.1RE0.05Ni solder was forced to spread instantly on the base metal surface under the action of ultrasonic vibration, and the ultrasonic cavitation can crush the oxide film on the surface of solder and base metal, resulting in the wetting of liquid solder and base metal. When the ultrasonic time was 3 s, the spreading area and spreading ratio of the solder achieved the maximum, and the ultrasonic cavitation could break the β-Sn and eutectic structure of the solder during solidification, refining the microstructure and improving the hardness of the solder matrix.
Thermoelectric Properties of Bi2Sr2CO2Oy/Cu2Se Composites
Authors: Li Erying , Liu Congbin , Song Hongzhang
Published: August 2019

The Cu2Se nanopowder was fabricated by the hydrothermal synthesis, then the thermoelectric properties of Bi2Sr2Co2Oy + x wt% Cu2Se (x = 0.0, 0.25, 0.50, 0.75, 1.00, and 1.25) composites prepared by the solid state method were investigated from room temperature to 875 K. The Cu2Se dispersant with an appropriate amount played a significant role in decreasing resistivity. Although the Seebeck coefficients also decreased slightly, the power factors of the doped samples got significant improvement. Furthermore, the thermal conductivity was depressed apparently. Ultimately, the Bi2Sr2Co2Oy + 0.5 wt% Cu2Se sample showed a better dimensionless figure of merit (ZT) value of 0.14 at 875 K. Compared with the pure Bi2Sr2Co2Oy sample, it was improved about by 25.5%.
Influence on Aggregation Structure Changes of Retired Cross-linked Polyethylene (XLPE) Cable Insulation under Pre-qualification Test
Authors: Wang Xiangbing , Liang Aiwu , Wang Yanfeng , Zhu Wenwei , Zhao Yifeng , Dai Xinyun , Fan Xinghui , Xie Yue , Liu Gang
Published: August 2019

In order to investigate the cross-linked polyethylene (XLPE) insulation characteristics of a retired high-voltage cable that has been in operation for 16 years and to evaluate the reliability of reusing it for practical operation, a 180-day pre-qualification test method was applied to a section of this cable to inspect the changes of aggregation structure. In this paper, the electric field and the thermal field of the inner, medium and outer positions of the insulation under the accelerated aging test were analyzed and converted to the corresponding equivalent condition at the surface of the conductor core. It can be found that equivalent testing conditions of the medium and outer positions are close to the cable practical operation condition. The diagnostic measurements of fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (X-ray) were conducted to analyse the aggregation structure of the samples. The results showed that the molecular chain of the inner position of the cable insulation was damaged and the crystalline structure was slightly degraded under high-strength test condition. On the contrary, the crystalline structure of medium and outer positions were both improved after the accelerated aging test because of the reduction of the impurities and the annealing effect. So it can be expected that the rest of this retired cables still have the potential to reuse in long-term actual operation condition.
Preparation of Boronic Acid-Functionalized Magnetic Nano-Particles by Polarity-regulating Molecular Self-assembly
Authors: Cheng Wenkai , Mo Pinjun , Chen Fei , Deng Meng , Xu Jinbao , Wang Wei , Zhong Guolun
Published: August 2019

Boronic acid-functionalized magnetic nanoparticles were prepared and characterized in this investigation. At first, the single-layer oleic acid-coated Fe3O4 magnetic nanoparticles were prepared by the chemical coprecipitation method and then the nanoparticles were surface-modified by a layer of poly(4-vinylphenylboronic acid) by the polarity-regulating molecular self-assembly technique to obtain the boronic acid-functionalized magnetic nanoparticles (Fe3O4@OA@BA). The resulted nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TGA), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM). The results show that the molecules of oleic acid can form the inner layer chemisorption on the surface of Fe3O4 and the double-layer coating structure on the outer layer. The poly(4-vinylphenylboronic acid) coated nanoparticles with content about 26% have an average size of 15 nm and the saturation magnetization of 43 emu/g. Finally, the adsorption effect of Fe3O4@OA@BA on bovine serum albumin (BSA) was studied. Under optimal adsorption conditions, the adsorption capacity on BSA is 135μg/mg, which embodies the superiority of molecular self-assembly to prepare functionalized nanoparticles.
Transfer Potential and Scheme Optimization of the Central Encryption Well Area of Block A-1
Authors: Wang Haiyong
Published: August 2019

After the encryption adjustment in the central encryption well area of block A-1, the production in the well area is improved, but at the same time, the production decline of old wells in the well area is accelerated, and water injection is not effective in some oil wells. In order to improve the wells development effect, the adjustment of injection-production system in this well area is analysed in detail, three transfer schemes are designed, the feasibility of different schemes is compared and analysed, it is preferred to select scattered transfer as the best transfer scheme.