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61.
Photocatalysts based on zinc hydroxide and a solid solution of CdS and ZnS were prepared via the precipitation method and used for photocatalytic hydrogen production from aqueous solutions of inorganic (Na2S/Na2SO3) and organic (ethanol) sacrificial agents. The photocatalysts were tested in cyclic experiments for hydrogen evolution and studied using X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy, high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS) techniques. Different transformations of the β-Zn(OH)2 co-catalyst were observed in the presence of inorganic and organic sacrificial agents; namely, ZnS was formed in Na2S/Na2SO3 solution, whereas the formation of ε-Zn(OH)2 was detected in solution with ethanol. The composite Zn(OH)2/Cd1−xZnxS photocatalysts have great potential in various photocatalysis processes (e.g., hydrogen production, CO2 reduction, and the oxidation of organic contaminants) under visible light.

The nature of the sacrificial agent affects the transformations of a Zn(OH)2 co-catalyst during photocatalytic hydrogen production.  相似文献   
62.
Previous cognitive vulnerability studies have identified sociotropy/dependency as a personality characteristic related to depression. We evaluated sociotropy in differential prediction of depression vs. anxiety. Participants (70 females, 42 males) were tested on the Beck Depression Inventory (BDI) and the Beck Anxiety Inventory (BAI) at two points in time (T1 and T2), separated by an interval of 4 weeks. The Sociotropy-Autonomy Scale (SAS) was administered at T1. Sociotropy was related moderately to the BDI at T1 and T2, but also to the BAI. Autonomy was related to neither. Hierarchical multiple regression analyses found sociotropy to predict anxiety at T2, but not depression. The issue of cognitive vulnerability marker specificity is discussed.  相似文献   
63.
64.
Non-alcoholic fatty liver disease (NAFLD) is one of the most prominent causes of liver-related morbidity in the Western world. NAFLD is a chronic disease charac...  相似文献   
65.
Journal of Neuro-Oncology - Primary central nervous system lymphoma (PCNSL) is a subtype of non-Hodgkin’s lymphoma that involves the brain, spinal cord, or leptomeninges, without evidence of...  相似文献   
66.
Metal matrix composites (MMCs) are a constantly developing class of materials. Simultaneously achieving a high strength and a high ductility is a challenging task in the design of MMCs. This article aims to highlight a recent trend: the development of MMCs reinforced with particles of core–shell structure. The core–shell particles can be synthesized in situ upon a partial transformation of metal (alloy) particles introduced into a metal matrix. MMCs containing core–shell particles with cores of different compositions (metallic, intermetallic, glassy alloy, high-entropy alloy, metal-ceramic) are currently studied. For metal core–intermetallic shell particle-reinforced composites, the property gain by the core–shell approach is strengthening achieved without a loss in ductility. The propagation of cracks formed in the brittle intermetallic shell is hindered by both the metal matrix and the metal core, which constitutes a key advantage of the metal core–intermetallic shell particles over monolithic particles of intermetallic compounds for reinforcing purposes. The challenges of making a direct comparison between the core–shell particle-reinforced MMCs and MMCs of other microstructures and future research directions are discussed.  相似文献   
67.
Background: We aimed to identify factors associated with the quality of life (QoL) of 'persons with dementia' (PWDs) and their family carers. Method: Two-hundred and thirty dyads of PWDs and their family carers were included. The PWDs were assessed with the Neuropsychiatric Inventory (NPI-Q), two Activities of Daily Living (ADL) scales, the Cornell Scale and the QoL-Alzheimer's Disease scale (QoL-AD; self- and proxy-reported scores). The carers were assessed with the QoL-AD and the Geriatric Depression Scale. Results: Factors associated with self-reported QoL were depression (β = -0.26, p < 0.001) and impaired ADL (β = -0.26, p < 0.001) and with proxy-rated QoL were NPI (β = -0.18, p = 0.02), depression (β = -0.32, p < 0.001) and impaired ADL (β = -0.43, p < 0.001). Factors associated with QoL in carers living together with the PWDs were depression (β = -0.56, p < 0.001) and having a hobby (β = 0.19, p = 0.01), whereas depression was associated with QoL in those who lived separately from the PWD (β = -0.60, p < 0.001). Conclusion: Depression and impaired ADL were associated with the self- and proxy-rated QoL of the PWDs, whereas depression in the carers negatively affected their QoL.  相似文献   
68.
Objectives: This study explores the association between coping, measured by the extent of locus of control, and the burden of care on family carers of persons with dementia (PWD).

Method: Two hundred thirty PWD living at home and their family carers were recruited from 20 Norwegian municipalities. The carers’ burden was assessed by the Relatives’ Stress Scale (RSS) and coping by the Locus of Control Behaviour Scale. The PWD were assessed by the Neuropsychiatric Inventory (NPI-Q), the Physical Self-Maintenance Scale (PSMS), the Instrumental Activities of Daily Living (IADL) scale, and the Mini Mental Status Examination (MMSE).

Results: Locus of control (LoC) was found to be the most important factor associated with the burden on carers of PWD, even when we had controlled for the PWD variables, such as the NPI-Q score. The LoC and the carer's use of hours per day to assist the PWD were the only two variables the carers found that affected the extent of the burden. The NPI-Q was the most important variable in the PWD that affected the burden on the carers.

Conclusion: Carers who believe that what happens to them is the consequence of their own actions are likely to be less burdened than carers not expecting to have control. This finding gives a possibility to identify carers with a high risk of burden.  相似文献   

69.
Amid the COVID-19 pandemic, a sudden surge in the production and utilization of disposable, single-use facial masks has been observed. Delinquency in proper disposal of used facial masks endangers the environment with a new form of non-biodegradable plastic waste that will take hundreds of years to break down. Therefore, there is an urgent need for the resourceful recycling of such waste in an environmentally friendly way. This study presents an efficient solution by using waste masks in fibered or crushed form to produce environmentally friendly and affordable green concrete. This investigation assessed the mechanical and durability properties of waste masks-incorporated concrete. A total of six mixes were prepared for standardized tests to determine compressive strength, split cylinder tensile strength and rapid chloride penetration test (RCPT), and freeze-thaw resistance. The percentage of mask fibers used were 0.5, 1, 1.5, and 2% of concrete by volume, while crushed masks were used at 0.5% only. The mask waste in both forms was found suitable to be used in concrete. One percent of waste mask fibers was found as an optimum value to increase compressive and tensile strength, reduce chloride permeability, and increase freeze-thaw resistance. Besides this, 0.5% crushed mask fiber also performed well, especially for producing less permeable and highly durable concrete. It is thus corroborated that waste masks that increase pollution worldwide can be utilized sustainably to help build green buildings. By reutilizing waste masks to produce improved concrete with better strengths and higher durability, circular economy and sustainability are achieved, along with efficient waste management.  相似文献   
70.
Flexural strength of concrete is an important property, especially for pavements. Concrete with higher flexural strength has fewer cracking and durability issues. Researchers use different materials, including fibers, polymers, and admixtures, to increase the flexural strength of concrete. Silicon carbide and tungsten carbide are some of the hardest materials on earth. In this research, the mechanical properties of carbide concrete composites were investigated. The silicon carbide and tungsten carbide at different percentages (1%, 2%, 3%, and 4%) by weight of cement along with hybrid silicon carbide and tungsten carbide (2% and 4%) were used to produce eleven mixes of concrete composites. The mechanical tests, including a compressive strength test and flexural strength test, along with the rapid chloride permeability test (RCPT), were conducted. It was concluded that mechanical properties were enhanced by increasing the percentages of both individual and hybrid carbides. The compressive strength was increased by 17% using 4% tungsten carbide, while flexural strength was increased by 39% at 4% tungsten carbide. The significant effect of carbides on flexural strength was also corroborated by ANOVA analysis. The improvement in flexural strength makes both carbides desirable for use in concrete pavement. Additionally, the permeability, the leading cause of durability issues, was reduced considerably by using tungsten carbide. It was concluded that both carbides provide promising results by enhancing the mechanical properties of concrete and are compatible with concrete to produce composites.  相似文献   
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