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"Yang, Lingling"
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Functional group characteristics of coal treated with clean biomass surfactant via FTIR spectroscopy
This study investigates the impact of a novel compound biomass surfactant on the molecular structure and functional group characteristics of Huainan Liuzhuang coal via Fourier Transform Infrared (FTIR) spectroscopy. The experimental results reveal marked differences between raw, distilled water-treated, and surfactant-modified samples, particularly in the transformation of hydroxyl, aliphatic, and oxygen-containing functional groups: (1) The coal’s IR spectra are categorized into four key absorption bands, representing hydroxyl groups, aliphatic hydrocarbons, oxygen-containing functional groups, and aromatic hydrocarbons. (2) Surfactant treatment reduces the total hydroxyl group content but increases hydroxyl-hydrogen bonding, enhancing coal’s structural stability. (3) The aliphatic side chains in modified coal become shorter, with the 3:7 compound ratio yielding the highest aliphatic group content. (4) C-O-C stretching vibrations condense into aryl ethers, increasing aromatic ring condensation, particularly at the 3:7 ratio. (5) Aromatic hydrocarbon diversity decreases as side chains detach from benzene rings, with ortho-trisubstituted structures (3 H) becoming more prominent. The outcomes demonstrate that compound biomass surfactant treatment induces significant functional group restructuring in coal, notably enhancing its wettability and gas desorption capacity, and providing promising avenues for application in coalbed methane recovery and spontaneous combustion prevention.
Journal Article
Miniaturized broadband high out-of-band rejection bandpass filter based on spoof surface plasmon polaritons with defected ground structure
In this paper, a novel compact bandpass filter (BPF) with a wide out-of-band rejection is proposed. It can achieve broadband characteristics by combining hollow bowtie-type spoof surface plasmon polaritons (SSPPs) with complementary H-type defected grounded structures (DGSs) through aperture coupling. Compared with the conventional SSPP unit cells, the hollow bowtie-type structure exhibits much better slow-wave characteristics. The introduced slant antenna type port-coupling can produce a very strong high-performance rejection outside the high frequency stopband. Simulation results show that the SSPPs-DGS-based BPF has an excellent band pass characteristics in a broadband range with − 3dB fractional bandwidth of 43.5% at center frequency
f
0
of 2.04 GHz. The return loss in the passband is better than − 12 dB. Furthermore, because of the multiple transmission zeros generated in upper-stop-band, the designed BPF has an extremely strong out-of-band rejection of -40dB from 1.5
f
0
to 4
f
0
(
f
0
is the center frequency). The designed SSPPs-DGS-based BPF is fabricated by conventional printed circuit board (PCB) technology with a compact size of only 0.68λ
g
*0.34λ
g
(λ
g
is the wavelength at the center frequency). The measured results have a good agreement with the simulation ones, which verifies the rationality and feasibility of the design. The miniaturized wideband BPF with broad out-of-band rejection may make it has good application prospect in the new generation microwave communication field.
Journal Article
Progress in the Medicinal Value, Bioactive Compounds, and Pharmacological Activities of Gynostemma pentaphyllum
Gynostemma pentaphyllum (Thunb.) Makino (GP), also named Jiaogulan in Chinese, was known to people for its function in both health care and disease treatment. Initially and traditionally, GP was a kind of tea consumed by people for its pleasant taste and weight loss efficacy. With the passing of the centuries, GP became well known as more than just a tea. Until now, numbers of bioactive compounds, including saponins (also named gypenosides, GPS), polysaccharides (GPP), flavonoids, and phytosterols were isolated and identified in GP, which implied the great medicinal worth of this unusual tea. Both in vivo and in vitro tests, ranging from different cell lines to animals, indicated that GP possessed various biological activities including anti-cancer, anti-atherogenic, anti-dementia, and anti-Parkinson’s diseases, and it also had lipid-regulating effects as well as neuroprotection, hepatoprotective, and hypoglycemic properties. With the further development and utilization of GP, the research on the chemical constituents and pharmacological properties of GP were deepening day by day and had made great progress. In this review, the recent research progress in the bioactive compounds, especially gypenosides, and the pharmacological activities of GP were summarized, which will be quite useful for practical applications of GP in the treatment of human diseases.
Journal Article
Echinacoside, an Inestimable Natural Product in Treatment of Neurological and other Disorders
Echinacoside (ECH), a natural phenylethanoid glycoside, was first isolated from Echinacea angustifolia DC. (Compositae) sixty years ago. It was found to possess numerous pharmacologically beneficial activities for human health, especially the neuroprotective and cardiovascular effects. Although ECH showed promising potential for treatment of Parkinson’s and Alzheimer’s diseases, some important issues arose. These included the identification of active metabolites as having poor bioavailability in prototype form, the definite molecular signal pathways or targets of ECH with the above effects, and limited reliable clinical trials. Thus, it remains unresolved as to whether scientific research can reasonably make use of this natural compound. A systematic summary and knowledge of future prospects are necessary to facilitate further studies for this natural product. The present review generalizes and analyzes the current knowledge on ECH, including its broad distribution, different preparation technologies, poor pharmacokinetics and kinds of therapeutic uses, and the future perspectives of its potential application.
Journal Article
The therapeutic potential of bone marrow mesenchymal stem cells in premature ovarian failure
With the development of regenerative medicine, a variety of mesenchymal stem cells (MSCs) are increasingly considered for the treatment of premature ovarian failure (POF). Reportedly, bone marrow-derived MSCs (BMSCs) improve the ovarian reserve, which mainly depends on homing and paracrine activities. Furthermore, paracrine factors secreted by these stem cells play an important role in ovarian recovery. Relevant studies indicate that BMSC transplantation has some positive effects on the treatment of POF in animals, but BMSCs are not widely applied in clinical therapy. Clinical trials are ongoing despite the fact that several patients experiencing BMSC transplantation recover their normal menstrual cycles and even give birth to babies. In this review, we discuss the possible therapeutic mechanisms of BMSCs for POF, migration, antiapoptosis, antifibrosis, angiogenesis, anti-inflammation, immunoregulation, and oxidative stress, which provide the theoretical basis for further study and clinical therapy.
Journal Article
Miniaturized broadband lowpass filter based on the integrated square dumbbell and meander structure spoof surface plasmon polaritons
A novel miniaturized broadband low-pass filter (LPF) is proposed based on the integrated square dumbbell and meander (SDBM) structure spoof surface plasmon polaritons (SSPPs). Compared with the conventional H-shaped and square dumbbell structure SSPP unit-cells, the integrated SDBM structure can effectively reduce its asymptotic frequency, revealing much better slow-wave characteristics. A broadband LPF is designed by integrating two types of SDBM structure SSPP unit-cell to enhance out-of-band suppression. Finite element method (FEM) simulations demonstrate that the SDBM structure SSPPs-based LPF exhibits excellent lowpass characteristics across a broadband range of 0–2.24 GHz, achieving a remarkably high out-of-band rejection level of − 27 dB in a broadband range of 2.39–8.7 GHz. An equivalent LC circuit model is established for the proposed SDBM-structured SSPPs-based LPF, exhibiting a reasonable consistency with the FEM results. The designed LPF is skillfully realized utilizing conventional PCB manufacturing techniques, achieving with a size of only 0.238
λ
c
× 0.12
λ
c
(λ
c
is the wavelength at cut-off frequency). The experimental results exhibit a remarkable consistency with the simulated data, thereby validating the soundness and practicality of the proposed design. The proposed broadband LPF featuring robust out-of-band rejection, demonstrates significant potential for integration into compact microwave and terahertz (THz) circuits, paving the way for advanced applications in these frequency bands.
Journal Article
Pore structure characteristics and fractal structure evaluation of medium- and high-rank coal
The presence of gas content in medium- and high-rank coal poses a threat to safety production. Safe gas extraction is based on a correct understanding of the pore structure of coal. This work investigates the pore structure characteristics of medium- and high-rank coal and evaluates their fractal structure. The coal samples were collected from Huainan Coalfield and Qinshui Coalfield, and divided into four types, according to the difference in surface bright characteristics. Through adopting low-temperature liquid nitrogen adsorption and desorption, and applying Kelvin equation, we obtain the main pore structure types and main pore size distribution characteristics of various coal briquettes. Electron microscope scanning structure and scientific analysis were used for special adsorption and desorption curves and hysteresis to find the dynamic reason. According to the different adsorption mechanism and Frenkel–Halsey–Hill-based model, with P/P₀ = 0.4 as the dividing point of fractal dimension analysis, the pore structure of coal samples is classified into five grades. The fractal evaluation results are consistent with the results of curve analysis and pore size analysis.
Journal Article
Association between air pollution and lifestyle with the risk of developing mild cognitive impairment and dementia in individuals with cardiometabolic diseases
Lifestyle factors and ambient air pollution are linked to dementia and CMDs, yet few studies have investigated their impact on dementia risk in CMDs patients at the same time. The Cox proportional hazards model was used to evaluate the influence of lifestyle and ambient air pollution on the dementia risk of the CMDs population among 438,681 participants in the UK Biobank. It is found that the risk of developing mild cognitive impairment and dementia in the population seems to increase with the increase in the number of CMDs. There appears to be a statistically significant association between high levels of ambient air pollution, unhealthy lifestyles, and a higher risk of developing mild cognitive impairment and dementia in the CMDs population. It is found that a healthy lifestyle may have an effect modifier role in the association between ambient air pollution and the risk of mild cognitive impairment and the development of dementia in patients with CMDs. Therefore, maybe people with CMDs can lessen the impact of ambient air pollution on their risk of developing mild cognitive impairment and dementia by improving their lifestyle.
Journal Article
A Decomposition-Ensemble Learning Model Based on LSTM Neural Network for Daily Reservoir Inflow Forecasting
Reservoir inflow forecasting is one of the most important issues in delicacy water resource management at reservoirs. Considering the non-linearity and of daily reservoir inflow data, a decomposition-ensemble learning model based on the long short-term memory neural network (DEL-LSTM) is developed in this paper for daily reservoir inflow forecasting. DEL-LSTM employs the logarithmic transformation based preprocessing method to cope with the non-stationary of the inflow data. Then, the ensemble empirical mode decomposition and Fourier spectrum methods are used to decompose the inflow data into the trend term, period term, and random term. For each decomposed term, a regression model based on the LSTM neural network is built to obtain the corresponding prediction result. Finally, the prediction results of the three items are integrated to get the final prediction result. Case studies on the Ankang reservoir in China have been conducted by using data from 1/1/1943 to 12/31/1971. Experimental results illustrated the superiority of the decomposition-ensemble framework and the LSTM neural network in forecasting daily reservoir inflow with big fluctuations. Comparing with some representative models, the proposed DEL-LSTM performs better in prediction accuracy, the average absolute percentage error is reduced to 13.11%, and the normalized mean square error is reduced by 4%, the coefficient of determination was increased by 5%.
Journal Article