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The article describes morphology studies on a solid MgCl2-based TiCl4 Ziegler-Natta catalyst for ethylene polymerization prepared via emulsion technique. Scanning electron microscopy (SEM) measurements revealed spherical catalyst particles with controllable diameter. The presenting of surfactant showed significantly influence on the morphology and particle diameter distribution of particles. The slurry polymerization of ethylene was studied with this catalyst system. The results showed that the catalyst had high activity and sensitive hydrogen responsibility. Polyethylene has good grain morphology because of duplicating the spherical morphology of the catalyst. [ABSTRACT FROM AUTHOR]

Synthesis of polypropylene from 1-propanol had been done. Polypropylene was synthesized via dehydration of 1-propanol using sulfuric acid catalyst followed with polymerization using AlCl3 catalyst to produce polypropylene. Structural characterization of products was done by means of IR spectrometer and the molecular weight of polypropylene was measured by viscometri Ubbelohde. Polymerization reaction by dehydration of 1-propanol using sulfuric acid catalyst produced propylene and followed with polymerization gave polypropylene in the molecular weight of 3900 g/mol with repetitive units of 93. [ABSTRACT FROM AUTHOR]

A simple statistical principle of chemical degradation system was derived by using isotactic poly(styrene). From a single TG-DTA curve, Tm (melting) and Td (degradation temperature) were obtained. These values were traced under different heating rates (20-0.6oC/min). The results were summarized as a function of heating time in a semi-logarithmic scale (Figure 3). It is indicated that a shaded area of the figures was almost constant irrespective of the heating rate employed (Figure 4), wh ich was directly connected with the thermal energy (dQ*) to cause the macroscopic thermal degradation. [ABSTRACT FROM AUTHOR]

In this work, high molecular weight polytetrafluoroethylene based antidripping agent was blended with Ziegler-Natta based LLDPE in different concentrations. Rheological characterization was consequently performed for all the blends and the obtained results were compared with the pure LLDPE. It has been found that high molecular weight PTFE based melt modifier MM 5935 EF significantly enhancing the shear viscosity/elasticity and especially the extensional viscosity of the LLDPE melt. [ABSTRACT FROM AUTHOR]

Properties such as lifetimes and masses of neutron-rich nuclei are key parameters for elucidating the astrophysical rapid neutron capture process (r-process). Due to the lack of experimental nuclear data in the relevant extremely neutron-rich region, especially near and above N = 126, the predictions of theoretical nuclear models are crucial for simulating r-process nucleosynthesis. Experimental studies of the properties and structures of neutron-rich nuclei from near the β stability line up to the r-process path provide important inputs to these theoretical models, improving the accuracy of predictions for the nuclear properties involved in the rprocess. We are developing the KEK Isotope Separation System (KISS) at the RIKEN RIBF facility to produce and separate these nuclei to perform spectroscopy experiments. The nuclei of interest are produced by multinucleon transfer reactions, which have been recently attracting renewed interest as they provide a way to access neutron-rich nuclei that are difficult to produce by other methods such as complete fusion or fragmentation. We have performed nuclear and laser spectroscopy, lifetime and mass measurements of neutron-rich nuclei of refractory elements near the N = 126 region using 198,natPt, natTa, natW, and natIr targets irradiated with 136Xe beams. We also extend our spectroscopic studies into the neutron-rich actinide region using 238U beams. This paper introduces the KISS facility and provides an overview of the nuclear spectroscopy experiments carried out there. We also introduce the KISS-1.5 project, which was started in FY2024 to further extend the research into the neutron-rich region. [ABSTRACT FROM AUTHOR]

There are still many cases of child sexual violence in Indonesia, showing how the government's dissonance in protecting children. Regional heads play an essential role in child protection policies, especially women's regional heads. In each vision, the head of the women's region prioritizes development based on gender mainstreaming. Unfortunately, there are still many cases of sexual violence in children in areas headed by female regional heads. The study focused on the perspective of women's leadership in tackling child sexual violence. This study aims to find out how policies deal with sexual violence in children from women's leadership. Through qualitative research methods combined with the perspective of feminism and gender mainstreaming as an analytical knife. Data collection techniques through data meta-synthesis. Data analysis uses a qualitative descriptive approach, then spelled out in the form of a narrative that begins with data collection, data filtering, data presentation, and conclusion withdrawal. The results showed that female regional heads were not a guarantee of controlling the problem of sexual violence in children. The failure to achieve the vision of the head of the female region in its implementation faced many obstacles, one of which was the social stigma attached to local women who were considered weak so that they could not protect children. This research suggests the need for the commitment and capability of female leaders to protect children and women. [ABSTRACT FROM AUTHOR]

High number of preterm births is one of the issues in improving health standard. The effort to help premature babies is hampered by high cost of NICU care in hospital. In addition, uneven distribution of electricity to remote area made it hard to operate the incubator. Utilization of phase change material beeswax to non-electricity incubator as heating element becomes alternative option to save premature babies. The objective of this experiment is to investigate the most efficient mass of beeswax according to Indonesian National Standard to earn over time and ideal temperature of incubator. Experiment was performed using prototype incubator, which utilizes natural convection phenomenon in the heating process of incubator. Utilization of fin is to accelerate heat distribution in the incubator. Result of experiment showed that the most efficient mass of PCM is 3 kg, which has 2.45 hours of running time for maintaining temperature of incubator in range of 32-36 °C. [ABSTRACT FROM AUTHOR]

Accurate modeling of γ-production in neutron capture reactions is critical for many applications including on-proliferation, safeguards and modeling nuclear reactors. To improve this work, the Rensselaer Polytechnic Institute (RPI) 16-segment γ-multiplicity NaI(Tl) detector at the Gaerttner Linear Accelerator (LINAC) Center has been upgraded by implementing a digital data acquisition system. The new digitized system records the γ-energy deposition distribution in each individual detector, and γ-multiplicity values as a function of neutron time-of-flight (TOF). With the new capabilities, high precision capture (and fission) yield measurements can be made, and the accuracy of simulation tools used to predict capture γ-cascades can be tested. To validate the updated system, an experiment was performed using a natural Ta sample to measure 181Ta and 180mTa resonance capture yield by detecting prompt γ-rays emitted from neutron capture interactions as a function of both neutron energy and measured γ-multiplicity of each capture event. The results confirm earlier measurements and agree with theoretical yield in the low energy resonance region from 1 to 20 eV. A 238U(n, γ) measurement was also performed to generate γ-spectra. For capture γ-cascades where the total γ-energy deposition is close to the neutron binding energy, γ-spectra were measured for individual resonance energies and observed γ-multiplicities. The results are comparable in shape to a recent measurement done using the Detector for Advanced Neutron Capture Experiments (DANCE) array at Los Alamos Neutron Science Center (LANSCE); however, differences need to be compared to Monte-Carlo n-particle simulations. [ABSTRACT FROM AUTHOR]

This research aims to study the electrical properties of bacterial cellulose (BC)/polypyrrole (Ppy) bio composite before and after withdrawal. A Wet BC pellicle is immersed with a liquid Ppy semiconductor, and then the sample is withdrawn. The results show that the electrical properties of the BC/Ppy bio composite change after the pullout. The sample without withdrawal shows homogeneous electrical resistance in various directions. However, the resistance in the withdrawal direction decreases by 28, 9 %, and the conductivity increases 153 % after withdrawal. This study can inform us that the electrical properties of BC/Ppy bio composite can change significantly due to deformation during sample preparation in wet conditions. The measurement results show that the conductivity level at point A (the probe is placed in the direction of with the direction of withdrawal) is better than the other measurements. This indicates that polypyrrole has succeeded in covering the TOBC/Ppy bio composite fibers which have been straight and dense, resulting in higher conductivity. [ABSTRACT FROM AUTHOR]

Background: While sociologists, urbanists, and city demographers have long explored residential mobility, researchers have focused almost entirely on voluntary mobility, neglecting until recently how involuntary displacement--disproportionately experienced by low-income individuals and households--may be consequential to health. Gaps remain about how residential instability, including forced moves, shape the health and health care of low-income patients with chronic illnesses in the U.S. health care safety net. Methods: Drawing on data from over two years of ethnographic fieldwork at urban safety-net clinics, we examine efforts by Complex Care Management (CCM) teams to stabilize patients with uncontrolled chronic illnesses through primary care-integrated support. Results: Our findings illustrate the range of challenges facing homeless and unstably housed individuals in the context of a regional affordable housing shortage. Residential instability and mobility work to create vulnerability for low-income chronically ill individuals, and in turn, poor health undermines safe, stable, and health-promoting places to live. Our findings capture the complex reciprocal, and often cyclical, relationship between residential instability and health. Conclusion: Low income individuals with precarious housing status simultaneously experience involuntary movement and involuntary immobility--forced out with eviction notices or higher rents and forced to stay in overcrowded and more expensive neighborhoods to be near their health care providers. [ABSTRACT FROM AUTHOR]

Ethylene-propylene random copolymers (EP-RACOs) of high flowability resp. melt flow rate (MFR) are important polymers for advanced thin-wall packaging articles. As impact strength retention over time is an important success factor here, two series of EP-RACOs based on different types of Ziegler-Natta catalysts (ZNC) were studied in ageing at ambient temperature. Through a combination of comonomer distribution and selective nucleation, the γ-phase content and consequently the long-term stability of injection molded parts can be improved significantly. [ABSTRACT FROM AUTHOR]

An advanced metal-ceramic brazing joint HfB2/NiB/HfB2, especially suitable for aerospace and energy applications, was subjected to instrumented nanoindentation at room temperature. A Berkovich pyramidal tip was utilized, with a prescribed maximum load equal to 200 mN, generating measured depths around one micrometer. By repeating the indentation experiments over a regular grid in a neighborhood of the joint, insights were provided into the mechanical properties of different phases and their spatial variability after the joining process, suggesting the possible infiltration of the braze and even the presence of residual stress fields. [ABSTRACT FROM AUTHOR]

To understand the evolution of dust properties in molecular clouds in the course of the star formation process, we constrain the changes in the dust emissivity index from star-forming filaments to prestellar and protostellar cores to T Tauri stars. Using the NIKA2 continuum camera on the IRAM 30 m telescope. we observed the Taurus B211/B2I3 filament at 1.2 mm and 2 mm with unprecedented sensitivity and used the resulting maps to derive the dust emissivity index β. Our sample of 105 objects detected in the β map of the B211/B213 filament indicates that, overal. β decreases from filament and prestellar cores (β ~ 2 ± 0.5) to protostellar cores (β ~ 1.2 ± 0.2) to T-Tauri protoplanetary disk (β < I). The averaged dust emissivity index β across the B211/B2I3 filament exhibits a flat (β ~ 2 ± 0.3) profile. This may imply that dust grain sizes are rather homogeneous in the filament, start to grow significantly in size only after the onset of the gravitational contraction/collapse of prestellar cores to protostars, reaching big sizes in T Tauri protoplanetary disks. This evolution from the parent filament to T-Tauri disks happens on a timescale of about 1-2 Myr. [ABSTRACT FROM AUTHOR]

Nozzle is considered as one of the most important parts of the rocket propulsion system. The thrust Produced by the Nozzle will determine the performance of the nozzle i.e., the amount of load that can be lifted by the nozzle against the gravity. Heavy rockets have nozzles that can lift higher loads. The thrust produced by the nozzle will depend on parameters such as velocity at exit of the nozzle, pressure at the exit of the nozzle and etc. The thrust produced by the nozzle will also depend on the type of the nozzle indirectly as various nozzles will have various properties. The exhaust gases produced after combustion when they pass through the nozzle the pressure energy of the flue gases will convert into the kinetic energy resulting the thrust required for the lift off. In this paper we designed the nozzles using Rocket propulsion analysis software and modelled using Solid works and analysed using ANSYS to determine the optimum nozzle design and the material is optimised by using the structural Analysis of the nozzles designed. The geometry parameters such as area expansion ratio, throat diameter and type of nozzle will influence the performance of the nozzle. The effect of the area expansion ratio on the performance will be discussed. [ABSTRACT FROM AUTHOR]

The 1960s saw the emergence of plastic as an indispensable component in various fields, including art and design. Acrylonitrile-butadiene-styrene (ABS) is widely used by artists and designers for a range of applications including sculptures and decorative pieces. Consequently, the necessity to conserve ABS from deterioration is a crucial issue in the field of cultural heritage preservation. Many studies have highlighted the criticality of the stability of the polybutadiene component when exposed to light. We propose a new multimodal spectroscopic approach to assess the conservation status of plastic design objects. This non-destructive approach combines correlative Brillouin and Raman micro-spectroscopy (BRaMS), external reflection IR spectroscopy and portable NMR relaxometry. BRaMS is a novel non-destructive technique in the field of heritage conservation, allowing simultaneous monitoring of chemical and mechanical changes occurring at the sample surface. The present study focused on photochemically aged LEGO® bricks made of ABS and aimed to i) correlate chemical and mechanical changes induced by light exposure and ii) introduce a surface degradation index (SDI), measurable in situ by external reflection IR spectroscopy, to assess the state of conservation of plastic artefacts. Finally, non-invasive investigations were carried out on real design objects using the MObile LABoratory (MOLAB) platform. [ABSTRACT FROM AUTHOR]

Throughout the 20th Century, plastics found extensive use in fashion, art, and design due to their versatile nature. However, their degradation over time poses challenges, impacting material integrity, particularly in museum collections. To tackle this issue, different scientific techniques have been employed to study polymers. In this work, a complementary multi-analytical approach is proposed to investigate the light stability of ABS compounds, selecting LEGO® bricks as reference material. The method is based on fluorescence emission and lifetime integrating point-like analysis and imaging systems to corroborate chemical and spatial information specifically addressed at the surface level. The latter has shown promising results in studying ABS objects, offering insights into degradation and aiding conservation efforts. [ABSTRACT FROM AUTHOR]

Here we have developed an advanced surface-enhanced Raman scattering (SERS) platform that enables the ultrasensitive, rapid and highly specific identification of tumour biomarkers in liquid biopsies. Our focus is on the detection of Thyroglobulin (Tg), the most important tumour biomarker for the diagnosis and prognosis of thyroid cancer. Specifically, SERS-active substrates fabricated by nanosphere lithography on chip or on tips of optical fiber (OF) were functionalised with Tg Capture antibodies. Gold nanoparticles were functionalized with Detection antibodies and conjugated with a Raman reporter. The sandwich assay platform was validated in the planar configuration and a detection limit of only 7 pg/ml was successfully achieved. A careful morphological characterisation of the SERS substrates allowed us to strictly correlate the coverage area with the Tg concentration. The same approach was successfully demonstrated in the washout of fine needle aspiration biopsies from cancer patients. The strategy was transferred to the Lab On Fiber (LOF) SERS platform and successfully used to detect Tg concentration. The proposed SERS-enhanced immunoassay platform has proven to be highly versatile and can be used with both microfluidic chip POC devices and SERS-OF-based optrodes to perform sensitive, specific and rapid ex vivo assays for Tg detection in liquid intraoperative biopsies. [ABSTRACT FROM AUTHOR]