Miracle-dz/UniFAR-FTUs huggingface dataset:
HPLC Method for Determining the Formaldehyde Content of Beer

Controlling the content of formaldehyde in beer is very important because of formaldehyde's toxicity. Nevertheless, accurate determination of its content in beer is difficult because of its low concentration in beer and reversible combination with sulfite. A selective and sensitive HPLC method for the determination of formaldehyde in beer, based on the derivatization of formaldehyde and 2,4-dinitrophenylhydrazine (DNPH), is described. Sample pretreatment was as follows: extraction of formaldehyde from beer through steam distillation of a beer sample preceded by adding 20 mL of phosphoric acid (concentration, 200 g/L) into 20 mL of beer and collection of 100 mL of distillate; mixing of 0.5 mL of the distillate and 1 mL of DNPH (concentration,1 g/L) in a 5-mL tube; and derivatizing for 20 min at 60°C. After derivatization, separation of the derivate was achieved using a C18 column (4 × 250 mm, 5 μm) and isocratic elution with 45% acetonitrile. This whole method enabled formaldehyde in beer to be determined with recoveries close to 100%, a repeatability error of less than 1%, and a limit of detection (LOD) of less than 3 μg/L. The overall method was successfully applied to the determination of formaldehyde in marketplace beers. The results showed that the concentration of formaldehyde in Chinese beers ranged from 0.062 to 0.453 mg/L, and the average content of formaldehyde in these beers was 0.134 mg/L.
The Impact of Motivation on the Employees in the Public Service Organisations: A Case of TEVETA, Lusaka, Zambia

One of the major problems faced in public service organisations is lack of motivation among public service employees. The objective of this study was to identify ways of motivating public service employees at TEVETA, Lusaka, Zambia. In order to achieve this objective a study was conducted using mixed research method (triangulation approach). Three specific research objectives with three related research questions were formulated. The theoretical framework for the study was premised on the Public Service Motivation (PSM) theory [9] Data for the qualitative research was collected using two focus group discussions and a questionnaire was also administered to collect quantitative data. The population was 68 employees with a sample size of 56 employees. The qualitative data was analysed by adopting a thematic approach. Quantitative data was analysed through the statistical package for social sciences (SPSS) to obtain descriptive statistical information. The two methods were used to help validate and ascertain the reliability of the research findings. The findings indicated that in addition to financial rewards, non-financial rewards were equally important and played a major role in motivating public service employees. The study findings identified several motivating factors, key motivators and also measures that can be used to motivate employees. These factors were classified into two categories, namely intrinsic motivating factors and extrinsic motivating factors. The researcher in this study made conclusions and came up with practical implications of the study as part of the recommendations, in terms of the ways that TEVETA can use to address the problems of low motivation among its employees. Furthermore, suggestions were made on the directions of future research on Public Service Motivation (PSM).
A survey on the blockchain techniques for the Internet of Vehicles security

Recently, The Internet of Vehicles (IoV) concept is becoming very popular due to sharing of the data between vehicles and the infrastructure. The sharing of data is very important for enhancing vehicular services, but at the same time makes IoV vulnerable for security and privacy issues. The smart and inter-connected vehicles produce sophisticated services for transport authorities, car manufacturers, vehicle owners, and other service providers. IoV are very vulnerable to malicious attacks due to its self-organizing nature and the open source nature of its implementations. This exposes the smart and interconnected vehicles to a variety of privacy and security threats, such as a remote hijacking or location tracking of vehicles. Thus, the security for IoV environment is critical. Blockchain technology has been recently used for cybersecurity due to the robustness and integrity preserving nature of its design. This review article provides a detailed survey of existing work in the literature to secure IoV through blockchain techniques such as security, privacy, reputation, distributed, decentralized, data sharing, authentication, and trust-based approaches. The paper presents the detailed discussion and analysis of these blockchain techniques to secure IoV. In addition, we present the gaps and research challenges identified from the existing research works. This provides work directions for future research in blockchain techniques to secure IoV.
Synthesis of Ni/Co/Al-layered triple hydroxide@brominated graphene hybrid on nickel foam as electrode material for high-performance supercapacitors

The determined need for a sustainable energy economy has evoked the increasing interest of researchers concerning the discovery of smart material designs of layered double hydroxide (LDH) nanocomposites for energy-based applications. This paper presents a novel method for the direct growth of brominated graphene and layered triple hydroxide (LTH) on 3D nickel foam (NF) as a supercapacitor electrode by a facile one-step in situ crystallization hydrothermal method. Subsequently, the as-synthesized NCA-L@BG-NF hybrids were characterized by TEM, SEM, HRTEM, XRD, FT-IR, RAMAN, XPS, and EDS. Moreover, the electrochemical performance disclosed that by fine-tuning the Ni/Co/Al mole ratios, it was possible to obtain optimized ratio of NCA-L@BG-NF-3 to display the maximum specific capacity of 1998 C g−1 at 6 A g−1, excellent rate capability of 75.3% at 20 A g−1, and excellent cyclic stability of ∼91% capacitance retention after 2000 cycles at 20 A g−1 with 100% coulombic efficiency. Furthermore, the greater electrochemical performance of LTH was achieved and synergistically strengthened with a high surface area provided by the conducting brominated graphene oxide framework directly grown on a 3D porous NF to form a binder-free electrode, which could improve the electrochemical performance in terms of charge transport and storage. Accordingly, these remarkable properties show that NCA-L@BG-NF-3 may be considered as a promising candidate for high-performance supercapacitor applications.
Penerapan Ekstraksi Keypoint Menggunakan Algoritma Scale-Invariant Feature Transform (SIFT) sebagai Dasar Melakukan Registrasi Point Cloud

Registrasi kumpulan titik dari citra (point cloud) merupakan tahap penting pada proses rekonstruksi dalam rangka membangun objek 3 dimensi. Salah satu algoritma yang sering digunakan untuk meregistrasi point cloud adalah Iterative Closest Point (ICP). Keterbatasan Algoritma ICP terletak pada proses pencarian korespondensi dari semua titik pada point cloud untuk menentukan transformasi, yang membutuhkan waktu yang panjang. Tujuan penelitian ini adalah mempersingkat waktu proses dengan melakukan ekstraksi keypoint menggunakan algoritma Scale Invariant Feature Transform (SIFT) sebelum proses registrasi point cloud dengan menggunakan algoritma Iterative Closest Point (ICP). Berdasarkan hasil uji coba menunjukkan bahwa tahap ekstraksi keypoint berhasil mendapatkan jumlah titik yang lebih sedikit sehingga dapat menurunkan waktu proses registrasi sebelumnya. Dengan demikian, dapat disimpulkan bahwa kombinasi algoritma SIFT dan ICP dapat diterapkan untuk registrasi point cloud tanpa mengubah objek asli dari point cloud.
Orange juice cloud stability and the influence of calcium and hesperidin

The cloud stability and physical properties of pulp free, fresh juice with and without ammonium oxalate (AO) at pH 4.0 and pH 5.5 was evaluated. The only juice to clarify in the three week study was the sample without AO at pH 4.0. Particle size analysis showed that the samples at pH 4.0 were larger than those at pH 5.5, and samples at pH 5.5 had a more negative zeta potential than samples at pH 4.0. In addition to electrostatic attraction and calcium binding, cloud particles associate and dissociate via non-covalent, non-electrostatic interactions. INDEX WORDS: Calcium chelation, Ammonium oxalate, Citrus juice cloud, Cloud stability
A Stress‐Free and Textured GaP Template on Silicon for Solar Water Splitting

This work shows that a large‐scale textured GaP template monolithically integrated on Si can be developed by using surface energy engineering, for water‐splitting applications. The stability of (114)A facets is first shown, based on scanning tunneling microscopy images, transmission electron microscopy, and atomic force microscopy. These observations are then discussed in terms of thermodynamics through density functional theory calculations. A stress‐free nanopatterned surface is obtained by molecular beam epitaxy, composed of a regular array of GaP (114)A facets over a 2 in. vicinal Si substrate. The advantages of such textured (114)A GaP/Si template in terms of surface gain, band lineups, and ohmic contacts for water‐splitting applications are finally discussed.
Electronic Properties of Typical Molecules and the Discharge Mechanism of Vegetable and Mineral Insulating Oils

Vegetable insulating oil may replace the mineral insulating oil used in large power transformers due to its extraordinary biodegradability and fire resistance. According to component analysis, 1-methylnaphthalene and eicosane are considered the typical molecules in mineral oil. Triolein and tristearin are considered the typical molecules in vegetable oil. The ionization potential (IP) and the variation of highest occupied molecular orbital (HOMO) of typical molecules under an external electric field are calculated using quantum chemistry methods. The calculation results show that the IP of the triolein molecule is comparable to that of the 1-methylnaphthalene molecule. The mechanisms of losing electrons are discussed, based on the analysis of HOMO composition. The insulation characteristics of the triolein and tristearin are more likely to be degraded under an external electric field than those of 1-methylnaphthalene and eicosane. Due to the fact that the number density of low IP molecules groups in vegetable oil is much greater than that in mineral oil, the polarity effect in vegetable oil is more obvious than that in mineral oil. This eventually leads to different streamer characteristics in vegetable oil and mineral oil under positive polarity and negative polarity.
In-vitro cytotoxicity of biosynthesized gold nanoparticles against thyroid cancer cell lines

Purpose: To undertake the biosynthesis of gold nanoparticles (AuNPs) using Shorea tumbuggaia bark extract and to study their in-vitro cytotoxicity in thyroid cancer (SW579) cell lines. Methods: AuNPs were prepared by adding 10 mL of Shorea tumbuggaia extract to 5 mL of 2 × 10 -3 M of chloroauric acid (HAuCl 4 ) and stirred at room temperature for about 20 min. The AuNPs were evaluated by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV–Vis) spectroscopy and transmission electron microscopy (TEM). They were also assessed for cytotoxicity against SW579 cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results: The reaction of Shorea tumbuggaia extract with HAuCl 4 led to a change in the color of the reaction solution to ruby red after 20 min, indicating the formation of AuNPs. The results of various instrumental tests, including XRD, TEM, UV–vis spectroscopy and FT-IR spectroscopy confirmed the formation of AuNPs. TEM images showed spherical NPs with a mean particle size of 20 nM. Further, in vitro cytotoxicity results indicated concentration-dependent cytotoxicity against SW579 cell lines. Conclusions: A simple, green and low-cost method for the preparation of AuNPs using Shorea tumbuggaia extract has been achieved. The AuNPs exert cytotoxic activity against SW579 cell lines. Keywords: Shorea tumbuggaia , Polyphenols, Gold nanoparticles, Cytotoxicity, Thyroid cancer cell
Influence of Sulfur Anion Doping on Visible-light Photocatalytic Activity of NaTaO3

: A novel NaTaO 3– x S x catalysts were successfully synthesized by one-step hydrothermal method using Ta 2 O 5 as starting material and Na 2 S 2 O 3 as sulfur source. Its catalytic mechanism and reaction process were tested by degradation experiment. The samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spec-troscopy (XRS), UV-Vis diffuse reflectance spectra (UV-Vis DRS) and X-ray diffraction (XRD). The results showed that the as-prepared S-doped NaTaO 3 did not display obvious variations to the surface charge and micro-morphology of NaTaO 3 . UV-Vis diffuse reflectance spectrum analysis indicated that S 2– partially substitute of O 2– ions in the lattice to form Ta–S–Ta bonds, and the light response range of the doped NaTaO 3– x S x samples extends to the visible region. The results of degradation experiment indicated that NaTaO 3– x S x exhibited much higher activity than that of pure NaTaO 3 . The reason is that in ten-time recycling test, S-doped NaTaO 3 displayed reliable recycling photocatalytic performance, whose photocatalytic efficiency kept at a high level and only existed very slight drop, due to the loss of photocatalyst during the reclaiming process.
Effect of The Addition of PEG and PVA Polymer for Gel Electrolytes in Dye-Sensitized Solar Cell (DSSC) with Chlorophyll as Dye Sensitizer

Dye-sensitized Solar Cell (DSSC) is a third-generation solar cell that consists of a working electrode, electrolyte and counter electrode. One of the most important parts of DSSC is an electrolyte that roles as a medium and regenerates the electron transport of electrons in the dye. However, the liquid electrolyte has a lack of stability in long-term use and easily evaporate or leak in DSSC. Therefore, this study aims to investigate an effect of the addition of polymer material such as PEG 1000, 4000 and PVA 60000 for fabricating a gel electrolyte to solve the problems of liquid electrolyte. The synthesized TiO2 nanoparticles used in this study was prepared using co-precipitation (CPT) method which produces TiO2 anatase phase with a crystal size of 11.1 nm. DSSC has been successfully conducted and analyzed to evaluate its performance. The results showed that the efficiency of DSSC cells using gel electrolyte prepared with PVA 60000 was better than a liquid electrolyte, PEG 1000, 4000, with the efficiency could be obtained at 0.083, 0.018, 0.033, and 0.054%, respectively. The results demonstrated that the addition PEG and/or PVA could be enhanced the performance of DSSC due to gel electrolyte produced current and voltage more stable compared to the liquid electrolyte.
Induction of Superhydrophobicity in a Cellulose Substrate by LbL Assembly of Covalently Linked Dual-Sized Silica Nanoparticles Layers

Micro/nano texturized oxidized cellulose membranes (MNOCM) were constructed by layer-by-layer (LbL) assembly in which a base cellulose film was modified by covalent linkages to amino-functionalized silica nanoparticles (amino-SiO2 NPs, 260 nm diameter) and epoxy-functionalized silica nanoparticles (epoxy-SiO2 NPs, 30 nm diameter). The amino-SiO2 NPs grafted onto the MNOCM surface through a standard amidation reaction between the amino groups of the SiO2 NPs and the carboxyl groups of the MNOCM surface in the presence of EDC and NHS consequently forming a first layer of large (260 nm) nanoparticles; subsequently, it was reacted with smaller (30 nm) epoxy-SiO2 NPs. Continuous repetitions of these alternating sized silica NPs through a standard LbL approach lead to a highly micro/nano-texturized MNOCM film as shown by SEM, which was ultimately sealed with a layer of hydrophobic PFOTES (1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane). Although the wettability of MNOCM was no longer hydrophilic, it was found that at five layers deep of NPs, it became superhydrophobic as evidenced by a water contact angle of 151° ± 2° and slide angle of 4°. The change in wettability was attributed to increases in final LbL layer surface roughness induced by the sufficient LbL layering of alternating sizes of NPs akin to what is observed in a lotus leaf surface. It was also noted that these superhydrophobic-MNOCM materials displayed good self-cleaning.
QKD optical ground terminal developments

Free space optical (FSO) satellite communications has very attractive properties for Quantum Key Distribution (QKD). The quantum channel loss and noise are major factors in setting the maximum achievable secure key rate of QKD systems. Primarily for a LEO satellite node and the BB84 protocol a number of technologies are proposed to reduce the quantum channel loss and noise. These technologies apply to the receiver side of the QKD link, the Optical Ground Terminal. It is shown that an optical beam shaper to optimize fiber mode matching, dedicated thermo-mechanical design to reduce misalignment induced by temperature gradients and an Adaptive Optics (AO) system to counteract optical turbulence effects can result in a significant reduction of loss and background noise. A breadboard verification experiment shows that using an medium-size AO system can maintain a fiber coupling efficiency up to 40%. The developed technologies have a general applicability with respect to satellite orbit and QKD protocol used.
Effects of aging on muscle activation patterns and postural control during sit-to-stand and balance recovery from medio-lateral perturbations across different initial foot positions

Rising from a sit to a stand has biomechanical factors that are dependent on initial foot position. However, little is known about the effects of different symmetric and asymmetric initial foot positions on leg muscle activation patterns during a sit-to-stand and balance maintenance of stance after a sit-to-stand. Three symmetric (neutral; both ankles positioned under the knees at a 90° flexion; one-third; and two-thirds foot length posterior to neutral) and three asymmetric (neutral non-dominant leg with one-third back dominant leg, neutral non-dominant with two-thirds back dominant leg, and one-third back nondominant leg with two-thirds back dominant leg) initial foot positions were tested. EMG of the lower extremity muscles and sagittal plane kinematic data were measured along with balance assessments in the anterior-posterior and medial-lateral axes. In the symmetric initial foot positions, a faster forward velocity of the body’s center of mass was required for more anterior initial foot positions. Even though the hip extensors activated earlier to decelerate the forward velocity of the body’s center of mass before rising, the greater forward velocity caused postural sway following completion of upright stance. In the asymmetric initial foot positions, the posterior leg supported more weight during the sitto-stand, resulting in balance perturbations in the posterior leg. In the one-third back non-
Development and validation of simple spectrophotometric, first and second derivative spectroscopy for estimation of Atovaquone in bulk and pharmaceutical formulations

A sensitive, selective and well validated spectrophotometric method using Tetrahydrofuran and Chloroform have been proposed for the determination of Atovaquone in pharmaceutical formulations which is widely used as antimalarial agent. The developed spectrophotometric method is simple, rapid, precise, accurate, reliable and economical when compared to other methods. The method was also applied for first and second derivative spectroscopy. The method shows better results in terms of accuracy, precision and linearity over a range of 20-100µg/ml for Tetrahydrofuran and 10-50 µg/ml for Chloroform. The limit of detection in Tetrahydrofuran and Chloroform are observed as 2 µg /ml and 5 µg/ml, the limit of quantification in Tetrahydrofuran and Chloroform are observed as 6 µg/ml and 15 µg/ml respectively. The %RSD is less than 2% in Chloroform and less than 1.5% in Tetrahydrofuran for precision. And the recovery is 99-101% in both the solvents. As a result the above method can be applied for bulk and finished product of Atovaquone.
Evaluation of the terrestrial carbon cycle, future plant geography and climate-carbon cycle feedbacks using five Dynamic Global Vegetation Models (DGVMs)

This study tests the ability of five Dynamic Global Vegetation Models (DGVMs), forced with observed climatology and atmospheric CO2, to model the contemporary global carbon cycle. The DGVMs are also coupled to a fast ‘climate analogue model’, based on the Hadley Centre General Circulation Model (GCM), and run into the future for four Special Report Emission Scenarios (SRES): A1FI, A2, B1, B2. Results show that all DGVMs are consistent with the contemporary global land carbon budget. Under the more extreme projections of future environmental change, the responses of the DGVMs diverge markedly. In particular, large uncertainties are associated with the response of tropical vegetation to drought and boreal ecosystems to elevated temperatures and changing soil moisture status. The DGVMs show more divergence in their response to regional changes in climate than to increases in atmospheric CO2 content. All models simulate a release of land carbon in response to climate, when physiological effects of elevated atmospheric CO2 on plant production are not considered, implying a positive terrestrial climate-carbon cycle feedback. All DGVMs simulate a reduction in global net primary production (NPP) and a decrease in soil residence time in the tropics and extratropics in response to future climate. When both counteracting effects of climate and atmospheric CO2 on ecosystem function are considered, all the DGVMs simulate cumulative net land carbon uptake over the 21st century for the four SRES emission scenarios. However, for the most extreme A1FI emissions scenario, three out of five DGVMs simulate an annual net source of CO2 from the land to the atmosphere in the final decades of the 21st century. For this scenario, cumulative land uptake differs by 494PgC among DGVMs over the 21st century. This uncertainty is equivalent to over 50 years of anthropogenic emissions at current levels.
Triple Bonds between Bismuth and Group 13 Elements: Theoretical Designs and Characterization

The effect of substitution on the potential energy surfaces of RE 13 ≡ BiR (E 13 = B, Al, Ga, In, and Tl; R = F, OH, H, CH 3 , SiH 3 , Tbt, Ar*, SiMe(Si t Bu 3 ) 2 , and Si i PrDis 2 ) is investigated using density functional theories (M06-2X/Def2-TZVP, B3PW91/Def2-TZVP, and B3LYP/LANL2DZ+dp). The theoretical results suggest that all of the triply bonded RE 13 ≡ BiR molecules prefer to adopt a bent geometry (i.e., ∠ RE 13 Bi ≈ 180° and ∠ E 13 BiR ≈ 90° ) , which agrees well with the bonding model (model (B)). It is also demonstrated that the smaller groups, such as R = F, OH, H, CH 3 , and SiH 3 , neither kinetically nor thermodynamically stabilize the triply bonded RE 13 ≡ BiR compounds, except for the case of H 3 SiB ≡ BiSiH 3 . Nevertheless, the triply bonded R ʹ E 13 ≡ BiR ʹ molecules that feature bulkier substituents (R ʹ = Tbt, Ar*, SiMe(Si t Bu 3 ) 2 , and Si i PrDis 2 ) are found to have the global minimum on the singlet potential energy surface and are both kinetically and thermodynamically stable. In other words, both the electronic and the steric effects of bulkier substituent groups play an important role in making triply bonded RE 13 ≡ BiR (Group 13 – Group 15) species synthetically accessible and isolable in a stable form.