Mechanism

In this study, we propose to build an equivalent 2D model to replace the 3D model of corrugated composite sheets, by the method of homogenization, to study the nonlinear mechanical behavior of corrugated core composite sheets. This model helps to significantly reduce the calculation time as well as the model building time. The model homogeneity is confirmed by comparing the numerical simulation results of the 2D model and the 3D model.

8p dathienlang1012 03-05-2024 2 0   Download

Bài giảng Xúc tác - Chương 6: Sự mất hoạt tính của xúc tác (Catalys deactivation). Chương này cung cấp cho học viên những nội dung gồm: các nguyên nhân và cơ chế (Causes and mechanisms); phương pháp phòng và xử lý (Prevention and treatment methods);... Mời các bạn cùng tham khảo!

22p mothuahoa 04-05-2024 5 2   Download

The efficient synthesis of 12-substituted-3,4,4a,5,12,12a-hexahydrobenzo[b]acridine-1,6,11(2H)-triones starting from 2-amino-1,4-naphthoquinone, 1,3-cyclohexanedione, and different (hetero)aromatic aldehydes was developed. These reactions were carried out in acetic acid under microwave irradiation in the presence of p-toluenesulfonic acid as catalyst. The structure of the newly synthesized compounds were confirmed employing spectroscopic data as well as elemental analysis. The plausible mechanism of these three-component domino reactions was also described.

7p dianmotminh02 03-05-2024 4 1   Download

In this study, we synthesized hydroxyapatite (HA) on polyvinyl alcohol/TiO2 (PVA/TiO2) in which TiO2 was prepared by the sol-gel method. HA was formed by immersing the membrane in the simulated body fluid (SBF) solution. We improved the mechanical strength of the membranes by adding glutaraldehyde (GA) combining with heat treatment to cross-link the polymer network.

14p dianmotminh02 03-05-2024 1 1   Download

In this study, the effect of alkaline-treated spent coffee grounds and compatibilizer on the mechanical properties of bio-composite based on polypropylene (PP) matrix was investigated. After alkaline treatment, the surface of spent coffee grounds became rougher; hence the PP matrix could better adsorb and encapsulate the treated coffee grounds compared with that of untreated ones. T

6p dianmotminh02 03-05-2024 3 1   Download

In conclusion, sequence analysis may be useful for the rapid detection of STR resistance in MDR M. tuberculosis strains, which in turn could contribute to better control strategies of TB in Vietnam. Other molecular mechanisms associated with STR resistance in STR-resistant strains without mutations in the rpsL and rrs genes need to be further investigated.

11p dianmotminh02 03-05-2024 4 1   Download

In the present report, a novel concept of frequency response function (FRF) is introduced for piezoelectric beam. First, a model of Timoshenko beam bonded with a piezoelectric layer is established and used for deriving the conventional frequency response function acknowledged as mechanical frequency response function (MERF). Then, the output charge produced in the piezoelectric layer is calculated from the MFRF and therefore obtained frequency-dependent function is called electrical frequency response function (EFRF) for the integrated beam.

16p dianmotminh02 03-05-2024 3 1   Download

In this work, nano-SiO2 have been used as nanocarriers for loading Ce(III) ions (SiO2@Ce3+). After loading, silane coupling agent has been used to modify these nanocarriers (m-SiO2@Ce3+). Then, these modified nanocarriers were added as green inhibitors into the inner epoxy coating matrix, which was based on the epoxy resin (DER 671X75) and hardener (polyamide Epicure 3125). Morphological study by FE-SEM showed that the spherical nanoparticles (mSiO2@Ce3+) were in size < 100 nm and dispersed rather homogeneously into the polyme matrix.

7p dianmotminh02 03-05-2024 3 1   Download

The 3D printing PMMA/ZrO2 filaments with a diameter of 1.75±0.05 mm were fabricated by using a single-screw extruder at temperatures of four heating zones of 190, 200, 210, and 210°C. Testing samples were prepared from the extruded filaments by using a fusion deposition modeling 3D printer and a Haake MiniJet piston injection molding machine. Fourier transform infrared spectroscopy, mechanical properties, field emission scanning electron microscopy (FESEM), differential scanning calorimetry, and thermogravimetric analysis of the filaments were investigated.

9p dianmotminh02 03-05-2024 1 1   Download

The present paper is focused on the impact of the dissolution mechanism of the different species (formed within a single bubble) on bubble chemistry. This process is analyzed on a range of ultrasound frequencies from 140 to 515 kHz, at an acoustic intensity of 1 W/cm². The obtained findings are compared to the results available in the literature.

14p dianmotminh02 03-05-2024 5 2   Download

natural fiber for the construction of hybrid bio-composites. In the current research project, a thorough analysis of the use of soy-PF resin for the creation of composites reinforced with jute was conducted. A novel and practical cutlery material was created after the mechanical properties were evaluated and optimized. In order to study the value addition of these newly proposed biocomposite materials as an ecological alternative in terms of natural resources versus synthetic resources, variables such as hardness, cytotoxicity, and degrading qualities of composites were also explored.

9p dianmotminh02 03-05-2024 5 2   Download

This study uses chitin as a filler for a polyurethane composite foam. The obtained polymer composite materials (PCM) are examined the technological parameters of the foaming (start time, rise time, and apparent density), the physical-mechanical properties (the compressive stress, compression set, resilience), and the cross-link density.

8p dianmotminh02 03-05-2024 5 3   Download

In this work, the free vibration analysis of Timoshenko microbeams made of the Functionally Graded Material (FGM) on the Winkler–Paternak elastic foundation based on the Modified Coupled Stress Theory (MCST) is investigated. Material characteristics of the beam vary throughout the thickness according to the power distribution and are estimated though Mori–Tanaka, Hashin–Shtrikman and Voigt homogenization techniques.

13p dianmotminh02 03-05-2024 8 2   Download

In this paper, we considered the propagation wave in transversely isotropic piezoelastic medium based on the nonlocal strain gradient theory. Two kinds of scale parameters, namely, the nonlocal parameter and the strain gradient parameter are introduced to account for the size effect of mechanical properties of nanostructures.

18p dianmotminh02 03-05-2024 6 2   Download

This paper examines the types of fraud in the financial affairs of public corporations and the way they deal with them and ultimately the right to judicial review. The results of the investigations showed that after proving any crime and issuing a lower court judgment, there is a right for the offender to seek authority from the authorities in order to obtain a reduction in the punishment. The multiplicity of judicial procedures is a mechanism and tool for correcting a mistake or probable judicial error.

4p longtimenosee10 26-04-2024 7 1   Download

The importance of supply chain governance mechanism has grabbed the attention of academia due to massive corporate scandals in 21st century. The following study is aimed to investigate the supply chain governance mechanism in Iraqi corporations at first stage and develop the relationship between supply chain governance with quality of financial reporting at second stage. The sample of this study is consists of listed Iraqi companies between the time period of 2009 to 2016.

4p longtimenosee10 26-04-2024 5 1   Download

The research subject is the process of economic and mathematical modelling of time series characterizing the bitcoin exchange rate volatility, based on the use of artificial neural networks. The purpose of the work is to search and scientifically substantiate the tools and mechanisms for developing prognostic estimates of the crypto currency market development. The paper considers the task of financial time series trend forecasting using the LSTM neural network for supply chain strategies.

5p longtimenosee09 08-04-2024 7 1   Download

Structural and spatial patterns of tree species in forests are important indicators to explain which underlying mechanisms or processes regulating forest structure. In this article, techniques of spatial point pattern analysis were used to characterize structural and spatial patterns of two secondary rain forest stands in Cuc phuong National park, Vietnam.

9p vilarry 01-04-2024 6 1   Download

Although the microbiome is established as an important regulator of health and disease, the role of viruses that inhabit asymptomatic humans (collectively, the virome) is less defined. While we are still characterizing what constitutes a healthy or diseased virome, an exciting next step is to move beyond correlations and toward identification of specific viruses and their precise mechanisms of beneficial or harmful immunomodulation.

3p vibransone 28-03-2024 2 2   Download

Bài viết Tác động của tín dụng ngân hàng đến tăng trưởng kinh tế khu vực tư nhân - bằng chứng thực nghiệm tại Việt Nam Nghiên cứu kiểm định tác động ngắn hạn và dài hạn của vốn tín dụng ngân hàng đối với phát triển kinh tế khu vực tư nhân ở Việt Nam, Nghiên cứu sử dữ liệu theo tần suất quý trong giai đoạn 2000-2021.

11p viwolverine 11-07-2023 9 5   Download