Effect of HPT on the First Hydrogenation of LaNi5 Metal Hydride

This paper reports the effect of high-pressure torsion (HPT) on the first hydrogenation of LaNi5. We found that, for loose powder, reduction of particle size has an effect of increasing the incubation time and decreasing the hydrogen capacity. A higher amount of HPT turns only marginally reduce the incubation time but has no effect on hydrogen capacity. In all cases, the first dehydrogenation and subsequent hydrogenation have the same kinetics, irrespective of the particle size or number of HPT turns. Therefore, for LaNi5, HPT has a beneficial effect only for the first hydrogenation.

Combustion Synthesis of Aluminum Oxynitride in Loose Powder Beds

This paper describes combusting loose powder beds of mixtures of aluminum metal powders and aluminum oxide powders with various grain sizes under various nitrogen pressure. The synthesis conditions required at least 20/80 weight ratio of aluminum metal powder to alumina powder in the mix to reach approximately 80 wt% of γ-AlON in the products. Finely ground fused white alumina with a mean grain size of 5 μm was sufficient to achieve results similar to very fine alumina with 0.3 μm grains. A lower nitrogen pressure of 1 MPa provided good results, allowing a less robust apparatus to be used. The salt-assisted combustion synthesis upon addition of 10 wt% of ammonium nitrite resulted in a slight increase in product yield and allowed lower aluminum metal powder content in mixes to be ignited. Increasing the charge mass five times resulted in a very similar γ-AlON yield, providing a promising technology for scaling up. Synthesis in loose powder beds could be utilized for effective production of relatively cheap and uniform AlON powder, which could be easily prepared for forming and sintering without intensive grounding and milling, which usually introduce serious contamination.

POWDER SOLUTION TECHNOLOGY REVIEW

Bioavailability and Solubility are the challenges for the formulation of highly lipophilic drugs. Oral routes of administration is one of the acceptable route due to improved patient compliance and convenience. Regularly newly advanced drug candidates are lipophilic, BCS Class II and IV drugs. Among various methods to improve the solubility of these drugs, liquid-solid technology or Powdered solution technology change the liquid drug into non-sticky, dry free-flowing, rapid release powder. This technique involves mixing of insoluble drug with nonvolatile solvent, admixing of drug-loaded excipients change into loose powder. This technique enhances major challenges like bioavailability with low production cost and a simple manufacturing process.

Formulation of Blush Preparations by Using Natural Coloring from Red Beetroot Extract (Beta vulgaris L.)

Beetroot (Beta vulgaris L.) has compounds that can be used for body health, beauty skincare, food additives, and much more. This research was aimed to prepare the dry extract of beetroot and formulate it into a loose powder, compact powder, and cream. The preparation was started by adding 2, 4, or 6% of dry extract, then blending the pulp and drying the resultant residue using a freeze dryer. Testing on color homogeneity, polishing, breakage, pH stability, color stability, and the hedonic test was carried out to determine the product quality. The initial result of phytochemical screening showed it might contain flavonoids, alkaloids, saponins, tannins, triterpenoids, steroids, and quinones. The color stability test performed at 30 °C showed that the cream was unstable while other forms showed fair stability at 8 °C. All dosage forms were homogeneous and could be applied easily. The breakage test showed no fractures. The pH remained stable for all formulas (between 3–5) after 28 days of storage. The color stability test showed that the significant discoloration only happened to the loose powder and cream. The hedonic test showed that the compact powder with a concentration of 6% was the most preferred formula by users.

Simplifying Sample Preparation for Soil Fertility Analysis by X-ray Fluorescence Spectrometry

Portable X-ray fluorescence (pXRF) sensors allow one to collect digital data in a practical and environmentally friendly way, as a complementary method to traditional laboratory analyses. This work aimed to assess the performance of a pXRF sensor to predict exchangeable nutrients in soil samples by using two contrasting strategies of sample preparation: pressed pellets and loose powder (<2 mm). Pellets were prepared using soil and a cellulose binder at 10% w w−1 followed by grinding for 20 min. Sample homogeneity was probed by X-ray fluorescence microanalysis. Exchangeable nutrients were assessed by pXRF furnished with a Rh X-ray tube and silicon drift detector. The calibration models were obtained using 58 soil samples and leave-one-out cross-validation. The predictive capabilities of the models were appropriate for both exchangeable K (ex-K) and Ca (ex-Ca) determinations with R2 ≥ 0.76 and RPIQ > 2.5. Although XRF analysis of pressed pellets allowed a slight gain in performance over loose powder samples for the prediction of ex-K and ex-Ca, satisfactory performances were also obtained with loose powders, which require minimal sample preparation. The prediction models with local samples showed promising results and encourage more detailed investigations for the application of pXRF in tropical soils.

Analisis Kadar Timbal (Pb) pada Bedak Tabur dan Eyeshadow dengan Variasi Metode Destruksi dan Zat Pengoksidasi dengan Spektroskopi Serapan Atom

<pre><span>Loose powder and eyeshadow are cosmetics often used by women in their daily activities. Some cosmetic products contain heavy metal in the composition.<em> </em></span><span lang="EN">This study aims to determine the concentration of lead in the loose powder and eyeshadow both registered and unregistered at the Food and Drug Supervisory Agency (BPOM) in Malang. The destruction method used is wet digestion in the opened and closed systems with variations of oxidizing agents of HNO₃ and HClO₄. The concentration of lead was analyzed using atomic absorption spectroscopy (AAS). The results of destruction optimization on loose powder and eyeshadow showed wet digestion in closed system gave the best destruction results. The best oxidizing agent for both products is a mixture of HNO₃: HClO₄ (2: 1). Lead concentration in the loose powder product for samples A, B, C, D was </span><span>18.90±0.35, 19.10±0.46, 23.47±0.65 and 28.90±0.35</span><span lang="EN">mg/Kg, respectively. Eyeshadow samples of E, F, G, and H contained lead concentrations were </span><span>25.67±1.76, 34.23±0.57, 45.30±0.56 and 45.90±1.78</span><span lang="EN"> mg/Kg, respectively</span></pre><pre>Keywords: cosmetics, loose powder, eyeshadow, lead</pre><p class="BodyAbstract"> </p><p class="BodyAbstract"> </p><p class="BodyAbstract">Bedak tabur dan eyeshadow merupakan kosmetik yang sering digunakan oleh wanita dalam kehidupaan sehari-hari. Beberapa produk kosmetik mengandung logam berat dalam komposisinya. Penelitian ini bertujuan untuk menentukan kadar timbal pada bedak tabur dan eyeshadow baik yang terdaftar dan tidak terdaftar di Badan Pengawas Obat dan Makanan (BPOM) di kota Malang. Metode yang digunakan adalah metode destruksi basah (terbuka dan tertutup) dengan variasi zat pengoksidasi HNO₃ dan HClO₄. Kadar timbal dianalisis menggunakan spektroskopi serapan atom (SSA). Hasil optimasi desktruksi pada bedak tabur dan eyeshadow menunjukkan bahwa destruksi basah tertutup memberikan hasil destruksi terbaik. Adapun pengoksidasi terbaik untuk kedua produk tersebut adalah campuran HNO₃:HClO₄ (2:1). Kadar timbal bedak tabur pada sampel A, B, C, D masing-masing sebesar 18,90±0,35; 19,10±0,46; 23,47±0,65 dan 28,90±0,35 mg/Kg. Sampel eyeshadow E, F, G, dan H mengandung kadar timbal sebesar 25,67±1,76; 34,23±0,57; 45,30±0,56 dan 45,90±1,78 mg/Kg, berturut-turut.</p><p class="BodyAbstract">Kata kunci: kosmetik, bedak tabur, eyeshadow, timbal</p>

Ni-NiO Porous Preform with Controlled Porosity Using Al2O3 Powder

The Ni-NiO skeleton seems to be a good candidate for various applications in industry such as corrosion-proof filters or components in refrigerating systems and as preforms for reactive infiltration with molten metals.The present work was focused on preparation of Ni-NiO composite with higher, controlled porosity. Sintering of pure Ni powder always leads to a substantial closed porosity in almost whole sample volume [1,2]. To eliminate this, we added Al2O3 particles with diameter of-32 +20 μm into the Ni powder (-75 +45 μm diameters) and sintered this loose powder mixture (Ni + 25 vol. % Al2O3) in air by progressive heating up to 800 °C followed by 2 hours isothermal exposure. As a control, pure Ni powder was sintered under the same conditions. Thermal oxidation of loose powder samples performed in alumina crucible indicates that the strongest oxidation occurred in the top part of sample, while the bottom part was the least oxidized. Therefore, it was necessary to run the thermal oxidation once more, but out of the crucible, to ensure the sufficient diffusion of oxygen to the whole volume of sample.

Loose powder detection and surface characterization in selective laser sintering via optical coherence tomography

Defects produced during selective laser sintering (SLS) are difficult to non-destructively detect after build completion without the use of X-ray-based methods. Overcoming this issue by assessing integrity on a layer-by-layer basis has become an area of significant interest for users of SLS apparatus. Optical coherence tomography (OCT) is used in this study to detect surface texture and sub-surface powder, which is un-melted/insufficiently sintered, is known to be a common cause of poor part integrity and would prevent the use of SLS where applications dictate assurance of defect-free parts. To demonstrate the capability of the instrument and associated data-processing algorithms, samples were built with graduated porosities which were embedded in fully dense regions in order to simulate defective regions. Simulated in situ measurements were then correlated with the process parameters used to generate variable density regions. Using this method, it is possible to detect loose powder and differentiate between densities of ±5% at a sub-surface depth of approximately 300 μm. In order to demonstrate the value of OCT as a surface-profiling technique, surface texture datasets are compared with focus variation microscopy. Comparable results are achieved after a spatial bandwidth- matching procedure.