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In order to uniformly disperse the ceramic reinforcements synthesized in-situ in the copper matrix composites, this study used Carbon Polymer Dot (CPD) as the carbon source and Cu–1.0%Ti alloy powder as the matrix for supplying Ti source to prepare in-situ synthesized TiC/Cu composites. The results show that TiC nano-precipitates, having the similar particle sizes with the CPD, form at the grains interior and grain boundaries, and maintain a uniform distribution state. Compared with the matrix, 0.3 ​wt% CPD/Cu composite displays the best strength-plastic compatibility, the ultimate tensile strength achieves 385 ​MPa accompanied with a corresponding elongation of 21%, owing to the dislocation hindrance caused by nano-carbide and excellent interface bonding between nano TiC and the Cu matrix. The density function theory calculation supports our experimental results by showing a tighter and stronger interface contact. This work presents a new approach for studying in-situ carbide precipitates.

Abstract Background Anxiety and depression are complications in Irritable bowel syndrome (IBS) patients. In this study, we recruited 18 IBS patients with mild-modest anxiety and depression behaviors, and after the screening, we defined the FMT treatment group (n = 9) and the control group (n = 9). The IBS symptom severity scale (IBS-SSS), Hamilton Anxiety Rating Scale (HAM-A), Hamilton Depression Rating Scale (HAM-D), Irritable Bowel Syndrome Quality of Life (IBS-QOL) and Bristol stool scale (BSS) were evaluated one week before FMT (baseline), one-week-, one-month-, two-month-, and three-month-following FMT. Meanwhile, we determined the SCFAs in the patient’s feces and serum and continued the metagenomic analysis of the microorganisms in the patient’s feces. Results The results showed that the patient’s anxiety and depression behavior gradually improved with FMT treatment. Moreover, the illness and quality of life had also been relieved significantly. The content of isovaleric acid and valeric acid was significantly reduced in the FMT group compared to the Col group. Metagenomic analysis showed that FMT treatment decreased the abundance of Faecalibacterium, Eubacterium and Escherichia. From KEGG functional analysis, we confirmed that the top five abundant pathways were “bacterial chemotaxis, “flagellar assembly”, “glycine, serine and threonine metabolism”, “apoptosis”, and “bacterial invasion of epithelial cells”. Conclusions FMT treatment can effectively alleviate the anxiety and depression behaviors of IBS-D patients and reduce the IBS-SSS score, indicating that FMT can improve patients’ symptoms. The high throughput sequencing results show that Bifidobacterium and Escherichia play the most critical role in the formation and recovery of IBS-D patients. The GC/MS data indicated that faeces isovaleric acid and valeric acid might be more suitable as a metabolic indicator of IBS-D remission. Trial registration ChiCTR, ChiCTR1900024924, Registered 3 August 2019, https://www.chictr.org.cn/showproj.aspx?proj=41676 .

The multi-wall carbon nanotube (MWCNT) reinforced alumina (Al _2 O _3 ) matrix composites were fabricated by spray drying and vacuum hot-pressing sintering. The mechanical properties of the composites with different mass fractions of MWCNT were studied. The flexural strength and fracture toughness of the composite were 498.3 MPa and 5.69 MPa·m ^1/2 , respectively, which were about 55.3% and 84.7% higher than that of pure Al _2 O _3 . With the increase in the content of MWCNT, the Vickers hardness and relative density of the composite decreased gradually. The correlation between the microstructure and the mechanical properties of the composite was analyzed.

Pakistan is a developing country whose maximum amount of mixed energy is provided by electricity, oil, coal, and gas. The study objective is to analyze the six major social factors to describe the significance of nuclear energy and CO2 emissions at the decisive point coming from income, trade, energy, and urbanization. This study has tried to analyze the impact of different factors (i.e., fossil energy, GDP per capita, overall population, urban population, and merchandise trade) on Pakistan's CO2 emissions using the extended STRIPAT model from 1986 to 2021. Ridge regression has been applied to analyze the parameters due to the multicollinearity problem in the data. The results show that (i) all the factors show significant results on carbon emissions; (ii) population and energy factors are the huge contributors to raising CO2 emissions by 0.15% and 0.16%; however, merchandise and GDP per capita are the least contributing factors by 0.12% and 0.13% due to import/export and income level in Pakistan, and (iii) nuclear energy and substitute overall show a prominent and growing impact on CO2 emissions by 0.16% and 0.15% in Pakistan. Finally, empirical results have wider applications for energy-saving, energy substitution, capital investment, and CO2 emissions mitigation policies in developing countries. Moreover, by investigating renewable energy technologies and renewable energy sources, insights are provided on future CO2 emissions reduction.

Financial structure is the primary director of economic activity in a capitalist society, it also has an important societal role in encouraging investments that are beneficial to the natural and human ecosystems. To accomplish this objective, this study addresses the unattended symmetric linkages between financial structure, energy depletion, and environmental degradation using multiple ecological footprints ‘’ (built-up land, carbon land, cropland, fishing grounds, forest products, and grazing land)’’ as an indicator over the period 1985 to 2018 for Pakistan. By using these six indicators as separate regressands, this research quantifies the impact of financial structure and energy depletion by applying the newly developed Augmented Autoregressive Distributed Lag (AARDL) approach. The outcome reveals that financial structure decreases ecological footprints, similarly, energy depletion also decreases ecological footprints. Opposite to it, trade openness increases ecological footprints, while urban population decreases ecological footprints. Given these results, comprehensive environmental and financial structure development policies are directed to achieve environmental sustainable goals.

An efficient enantioselective Mannich reaction of N-protected α-sulfones with β-benzenesulfonyl phosphonates was developed by using a chiral cinchona alkaloid-derived thiourea as a catalyst. This method was used to obtain a series of chiral α-sulfonyl-β-aminophosphonates in yields of up to 96% with 89:11 dr and 88% ee. These compounds were further transformed into β-aminophosphonates or chiral azetidines with various functional groups by a Horner--Wadsworth--Emmons/aza-Michael addition reaction sequence. [ABSTRACT FROM AUTHOR]

An energy extraction technology based on motion-constrained tandem oscillating hydrofoils is presented in this paper. The turbine for extracting energy from the flow field is designed and built based on the measured frequency and energy extraction performance analysis of motion-constrained tandem oscillating hydrofoils. The instantaneous rotating speed and torque for the output shaft of the turbine are measured using a torque meter to determine the instantaneous power extracted by the turbine. Experimental results for this energy extraction turbine show that the optimal reduced frequency for both a single oscillating hydrofoil and tandem oscillating hydrofoils is about 0.1 and that the cycle-averaged energy extraction efficiency of the turbine with motion-constrained tandem oscillating hydrofoils reaches 29.2%. [ABSTRACT FROM AUTHOR]

Currently, Pakistan is in a stage of urbanization and industrialization, raising its energy demand and supply and carbon dioxide emissions (CO2Es) due to the excessive use of fossil fuels. In meeting future demand and supply predictions, much emphasis should be given to both energy consumption and the level of inter-factor and inter-fuel substitution possibilities. Specifically, future outcomes for energy demand are more valid when production models contemplate substitution elasticity occurring during the period. To analyze the potential for little reliance on fossil fuels and diminish CO2Es, the present research has examined the potential for the substitution of energy and non-energy factors (i.e., natural gas, electricity, petroleum, labor, and capital) by using translog productions function over the period between 1986–2019. The ridge regression method is applied to evade the multicollinearity issue in the data. The model analyzes the output elasticity, substitution elasticity, technical progress, and carbon emission scenarios. The results show that the output elasticities are growing, presenting that the contribution of all factors adds to economic growth. The inputs between capital-petroleum, capital-electricity, labor-electricity, capital-natural gas, and natural gas-electricity are extreme substitutes. These substitutes are increasing capital growth and production sizes. The relative difference in technical progress shows a small positive change between 3–7% with convergence evident. Lastly, the investment scenarios under 5% and 10% investment in petroleum reduction are evidence that the CO2Es would reduce by 7.5 Mt and 10.43 Mt under scenario 1 and 7.0 Mt and 10.9 Mt under scenario 2. The results have broader suggestions for energy-conserving policies, particularly under the China–Pakistan Economic Corridor.

Low-carbon energy transformation is a major trend in world energy development, and measures to mitigate carbon emissions can vary substantially in terms of the energy they require. A common method of evaluating energy use in energy resource exploitation is energy return on investment (EROI). One of the criticisms of EROI concerns uncertainty regarding the input and output factors for the calculation. To make the issue clear, we interpret EROI in terms of entropy, which is the most basic concept in physics. We consider an energy resource exploitation system to be a kind of dissipative structure and construct a basic entropy analysis framework for an energy resource exploitation system. We then derive the relationship between EROI and entropy change. The theory of EROI is consistent with the basic requirement for a dissipative structure, which is that the total entropy change must be negative. EROI is a method of using entropy theory to evaluate energy resource exploitation. It is inappropriate and unnecessary to quantify all factors as energy units as the input and output factors are multidimensional while energy is a one-dimensional standard. Future development of the EROI method should be guided by entropy theory. A series of EROI related indicators will increase its application and policy significance.

The low-carbon transformation of the power industry is of great significance to realize the carbon peak in advance. However, almost a third of China’s CO2 emissions came from the power sector in 2019. This paper aimed to identify the key drivers of CO2 emissions in China’s power industry with the consideration of spatial autocorrelation. The spatial Durbin model and relative importance analysis were combined based on Chinese provincial data from 2003 to 2019. This combination demonstrated that GDP, the power supply structure and energy intensity are the key drivers of CO2 emissions in China’s power industry. The self-supply ratio of electricity and the spatial spillover effect have a slight effect on increasing CO2 emissions. The energy demand structure and CO2 emission intensity of thermal power have a positive effect, although it is the lowest. Second, the positive impact of GDP on CO2 emissions is decreasing, but that of the power supply structure and energy intensity is increasing. Third, the energy demand of the industrial and residential sectors has a greater impact on CO2 emissions than that of construction and transportation. For achieving the CO2 emission peak in advance, governments should give priority to developing renewable power and regional electricity trade rather than upgrading thermal power generation. They should also focus on promoting energy-saving technology, especially tapping the energy-saving potential of the industry and resident sectors.

While there is evidence that the development and course of major depressive disorder (MDD) symptomatology is associated with vascular disease, and that there are changes in energy utilization in the disorder, the extent to which cerebral blood flow is changed in this condition is not clear. This study utilized a novel imaging technique previously used in coronary and stroke patients, 320-slice Computed-Tomography (CT), to assess regional cerebral blood flow (rCBF) in those with MDD and examine the pattern of regional cerebral perfusion. Thirty nine participants with depressive symptoms (Hamilton Depression Rating Scale 24 (HAMD24) score > 20, and Self-Rating Depression Scale (SDS) score > 53) and 41 healthy volunteers were studied. For all subjects, 3 ml of venous blood was collected to assess hematological parameters. Transcranial Doppler (TCD) ultrasound was utilized to measure parameters of cerebral artery rCBFV and analyse the Pulsatility Index (PI). 16 subjects (8 = MDD; 8 = healthy) also had rCBF measured in different cerebral artery regions using 320-slice CT. Differences among groups were analyzed using ANOVA and Pearson's tests were employed in our statistical analyses. Compared with the control group, whole blood viscosity (including high\middle\low shear rate)and hematocrit (HCT) were significantly increased in the MDD group. PI values in different cerebral artery regions and parameters of rCBFV in the cerebral arteries were decreased in depressive participants, and there was a positive relationship between rCBFV and the corresponding vascular rCBF in both gray and white matter. rCBF of the left gray matter was lower than that of the right in MDD. Major depression is characterized by a wide range of CBF impairments and prominent changes in gray matter blood flow. 320-slice CT appears to be a valid and promising tool for measuring rCBF, and could thus be employed in psychiatric settings for biomarker and treatment response purposes.