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1.
Adv Mater ; 36(12): e2209460, 2024 Mar.
Article in English | MEDLINE | ID: mdl-36638501

ABSTRACT

Water-based evaporative cooling is emerging as a promising technology to provide sustainable and low-cost cold to alleviate the rising global cooling demand. Given the significant and fast progress made in recent years, this review aims to provide a timely overview on the state-of-the-art material design and engineering in water-based evaporative cooling. The fundamental mechanisms and major components of three water-based evaporative cooling processes are introduced, including direct evaporative cooling, cyclic sorption-driven liquid water evaporative cooling (CSD-LWEC), and atmospheric water harvesting-based evaporative cooling (AWH-EC). The distinctive requirements on the sorbent materials in CSD-LWEC and AWH-EC are highlighted, which helps synthesize the literature information on the advanced material design and engineering for the purpose of improving cooling performance. The challenges and future outlooks on further improving the water-based evaporative cooling performance are also provided.

2.
Materials (Basel) ; 14(8)2021 Apr 08.
Article in English | MEDLINE | ID: mdl-33917648

ABSTRACT

Catalytic packed bed filters ahead of gas sensors can drastically improve their selectivity, a key challenge in medical, food and environmental applications. Yet, such filters require high operation temperatures (usually some hundreds °C) impeding their integration into low-power (e.g., battery-driven) devices. Here, we reveal room-temperature catalytic filters that facilitate highly selective acetone sensing, a breath marker for body fat burn monitoring. Varying the Pt content between 0-10 mol% during flame spray pyrolysis resulted in Al2O3 nanoparticles decorated with Pt/PtOx clusters with predominantly 5-6 nm size, as revealed by X-ray diffraction and electron microscopy. Most importantly, Pt contents above 3 mol% removed up to 100 ppm methanol, isoprene and ethanol completely already at 40 °C and high relative humidity, while acetone was mostly preserved, as confirmed by mass spectrometry. When combined with an inexpensive, chemo-resistive sensor of flame-made Si/WO3, acetone was detected with high selectivity (≥225) over these interferants next to H2, CO, form-/acetaldehyde and 2-propanol. Such catalytic filters do not require additional heating anymore, and thus are attractive for integration into mobile health care devices to monitor, for instance, lifestyle changes in gyms, hospitals or at home.

3.
Cancer Sci ; 106(1): 43-50, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25421527

ABSTRACT

This study aimed to induce malignant transformation of endometriosis in Sprague-Dawley rats by hyperestrogenemia and type II diabetes and evaluate its similarity with human disease in biological features. Rats with surgically induced endometriosis were randomized into two groups: those treated with estradiol (5 mg/kg three times/week after surgery), streptozotocin (25 mg/kg, 1 month after surgery), and high carbohydrate-and-fat feed (Es group); and those treated with placebo saline and standard feed (control group). All rats were randomly killed 2, 4, or 8 months after surgery. The endometriosis lesions and the corresponding eutopic endometria were subjected to morphological evaluation, TUNEL, and immunohistochemical analysis for the expressions of proliferating cell nuclear antigen, phosphatase and tensin homolog, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin proteins. In the Es group, three cases (6.0%) of endometriosis showed atypical hyperplasia accompanied by simple hyperplastic eutopic endometria, and two cases (4.0%) of endometriosis showed endometrioid carcinoma accompanied by atypical hyperplastic eutopic endometria. In the Es group, the activity of organelles and the expressions of proliferating cell nuclear antigen, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin increased, and the level of phosphatase and tensin homolog and TUNEL positivity decreased progressively in the order of endometriosis, atypical endometriosis, and malignant endometriosis. The same tendency was found in the corresponding eutopic endometria. The induced malignant endometriosis showed similarities with human disease in the pathological process and histomorphological and molecular biological features. The method is feasible. The malignant transformations of endometriosis and eutopic endometria may have correlations and similarities, but the former may suffer a higher risk of canceration.


Subject(s)
Adenocarcinoma/etiology , Diabetes Mellitus, Experimental/complications , Endometrial Neoplasms/etiology , Endometriosis/pathology , Estrogens/blood , Animals , Apoptosis , Cell Proliferation , Cell Transformation, Neoplastic , Endometrium/metabolism , Endometrium/pathology , Estrogens/physiology , Female , PTEN Phosphohydrolase/metabolism , Rats, Sprague-Dawley
4.
Ying Yong Sheng Tai Xue Bao ; 26(9): 2794-802, 2015 Sep.
Article in Chinese | MEDLINE | ID: mdl-26785563

ABSTRACT

To explore the dynamic process of restoration succession in degraded alpine meadow that had been disturbed by plateau zokors in the eastern Tibetan Plateau, we examined soil nutrients and microbial functional diversity using conventional laboratory analysis and the Biolog-ECO microplate method. Our study showed that: 1) The zokors disturbance significantly reduced soil organic matter, total nitrogen, available nitrogen and phosphorus contents, but had no significant effects on soil total phosphorus and potassium contents; 2) Soil microbial carbon utilization efficiency, values of Shannon, Pielou and McIntosh indexes increased with alpine meadow restoration years; 3) Principal component analysis (PCA) showed that carbohydrates and amino acids were the main carbon sources for maintaining soil microbial community; 4) Redundancy analysis ( RDA) indicated that soil pH, soil organic matter, total nitrogen, available nitrogen, and total potassium were the main factors influencing the metabolic rate of soil microbial community and microbial functional diversity. In summary, variations in soil microbial functional diversity at different recovery stages reflected the microbial response to aboveground vegetation, soil microbial composition and soil nutrients.


Subject(s)
Environmental Restoration and Remediation , Grassland , Soil Microbiology , Soil/chemistry , Carbon/chemistry , Nitrogen/chemistry , Phosphorus/chemistry , Tibet
5.
Ying Yong Sheng Tai Xue Bao ; 23(11): 3072-8, 2012 Nov.
Article in Chinese | MEDLINE | ID: mdl-23431793

ABSTRACT

By using phospholipid fatty acid (PLFA) method, this paper studied the changes of soil microbial community structure in an alpine meadow under six years continuous enclosure and its combination with fertilization, taking grazing area as the control. Both continuous enclosure and its combination with fertilization had significant effects on the microbial flora and total PLFA in different soil layers, and the effects were greater for 0-10 cm than for 10-20 cm soil layer. The species of PLFA in different soil layers also changed significantly. Under enclosure and its combination with fertilization, the number of gram-negative bacteria in different soil layers was lower than that of the control, and the numbers of bacteria, fungi, and gram-positive bacteria and the total PLFA in 0-10 cm soil layer were also lower, but the number of actinomycetes was higher than that of the control. In 10-20 cm soil layer, the number of gram-positive bacteria had no significant differences among different treatments, whereas the numbers of bacteria, fungi, and actinomycetes and the total PLFA were notably higher under enclosure but decreased markedly after fertilization. As compared with that of the control, the ratio of bacteria and fungi in different soil layers under enclosure and its combination with fertilization increased, the ratios of saturated fatty acid to monounsaturated fatty acid (SAT/MONO) and of gram-positive bacteria to gram-negative bacteria (G+/G-) under enclosure were all lower, but those after fertilization were in adverse. It was suggested that continuous enclosure and its combination with fertilization led to the decline of soil microbial diversity and activity and soil ecosystem stability.


Subject(s)
Fertilizers , Herbivory , Poaceae/growth & development , Soil Microbiology , Altitude , Animals , Bacteria/growth & development , Colony Count, Microbial , Fungi/growth & development
6.
Ying Yong Sheng Tai Xue Bao ; 22(6): 1416-22, 2011 Jun.
Article in Chinese | MEDLINE | ID: mdl-21941739

ABSTRACT

Taking the typical alpine meadows Potentilla froticosa shrub meadow, Kobresia humilis meadow, and K. pygmaea meadow in the Haibei State of Qinghai Province as the research objects, a comprehensive assessment of soil quality was conducted by principal component analysis (PCA), with seven indices of soil microbial activities and ten indices of soil chemical properties. The soil quality of the alpine meadow could be characterized by three principal components (PC). In the first component (PC1), 13 indices had high factorial loads; in the second component (PC2), 3 indices had high factorial loads; in the third component (PC3), only one index, total phosphors, had high factorial load. In combining with Norm values, eleven indices including microbial biomass carbon (MBC), urease, alkaline phosphatase, protease, organic matter, total N, available N, available P, available K, bulk density, and CEC were selected to establish minimum data set (MDS) for the comprehensive assessment of soil quality of alpine meadow in Haibei. The PCA and corresponding weight coefficient analysis showed that the soil quality (0-10 cm and 10-20 cm layers) of the three kind meadows was in the order of K. humilis meadow > P. froticosa shrub meadow > K. pygmaea meadow, and P. froticosa shrub meadow > K. pygmaea meadow > K. humilis meadow, respectively.


Subject(s)
Cold Temperature , Phosphorus/analysis , Poaceae/growth & development , Soil Microbiology , Soil/analysis , Altitude , China , Ecosystem , Principal Component Analysis
7.
Ying Yong Sheng Tai Xue Bao ; 20(11): 2646-51, 2009 Nov.
Article in Chinese | MEDLINE | ID: mdl-20135995

ABSTRACT

An investigation was made on the plant communities of artificial grasslands established for different years in headwater region of Yangtze River and Yellow River, and the related soil physical and chemical properties and soil microbial physiological groups were analyzed. With the increase of establishment years, most of plant communities on the grasslands showed a "V" type change trend in their quantities, i.e., high-low-high, but the forbs biomass had a "A" type change trend and the sedge biomass increased gradually. Soil nutrients presented a "V" type but soil bulk density presented a "A" type change trend, while soil pH presented a decreasing trend. Most of soil microbial physiological groups and microbial biomass carbon showed a "V" type change trend, phosphorus-dissolving bacteria showed a "A" type change trend, denitrifying bacteria decreased gradually, while cellulose-decomposing bacteria showed an increasing trend. The numbers of soil microbes had a close relationship with tested soil factors, and the soil microbial physiological groups were directly or indirectly affected by the soil factors. All the results indicated that the establishment of artificial grassland and the positive succession of vegetation could effectively improve soil physical and chemical properties, which benefit for the beneficial microbes to settle down and propagation, while proliferation of the non-beneficial microbes was inhibited.


Subject(s)
Bacteria/classification , Conservation of Natural Resources , Poaceae/growth & development , Soil Microbiology , Bacteria/growth & development , Biomass , China , Ecosystem , Poaceae/classification , Population Dynamics , Rivers
8.
Ying Yong Sheng Tai Xue Bao ; 18(11): 2426-31, 2007 Nov.
Article in Chinese | MEDLINE | ID: mdl-18260442

ABSTRACT

This paper studied the biomass, species composition, and diversity index of artificial grassland plant communities with different establishment duration in the source region of the Three Rivers, and examined the relationships of soil physical and chemical properties with the changes of the plant community biomass and species diversity. The results showed that the species composition, functional group composition, and quantitative characters of the plant communities varied greatly. Soil moisture content increased with increasing species diversity, while soil bulk density was in adverse. Soil microbial biomass carbon significantly positively correlated with soil moisture and organic matter contents, but negatively correlated with soil bulk density. Soil organic carbon content had a "V" type change, which was consistent with the change pattern of soil moisture content, and decreased with increasing soil bulk density. Plant community biomass had significant positive correlations with the contents of soil nutrients and moisture, and the increase of the above- and below-ground biomass of plant communities promoted the increase of soil nutrient contents.


Subject(s)
Ecosystem , Poaceae/growth & development , Soil/analysis , Biodiversity , Biomass , Carbon/analysis , China , Poaceae/classification , Population Dynamics , Rivers , Soil Microbiology
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