Publications by authors named "Wen-Wei Chen"

The growth of hexagonal boron nitride (hBN) directly onto semiconducting substrates, like Ge and Ge on Si, promises to advance the integration of hBN into microelectronics. However, a detailed understanding of the growth and characteristics of hBN islands and monolayers on these substrates is lacking. Here, we present the growth of hBN on Ge and Ge epilayers on Si high-vacuum chemical vapor deposition from borazine and study the effects of Ge sublimation, surface orientation, and vicinality on the shape and alignment of hBN islands.

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Soil microorganisms play an important role in the biogeochemical cycles of terrestrial ecosystems. How-ever, it is still unclear how the amount and duration of nitrogen (N) addition affect soil microbial community structure and whether there is a correlation between the changes in microbial community structure and their nutrient limi-tation status. In this study, we conducted an N addition experiment in a subtropical forest to simulate N deposition with three treatments: control (CK, 0 kg N·hm·a), low N (LN, 40 kg N·hm·a), and high N (HN, 80 kg N·hm·a).

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Priming effect (PE) plays an important role in regulating terrestrial soil carbon (C) cycling, but the impact of different C addition modes on the PE in subtropical forest ecosystems with increasing nitrogen (N) deposition is unclear. In this study, we investigated the effects of C addition patterns (single or repeated C addition) on soil PE by adding C-labeled glucose for 90 d in an incubation experiment with different levels of N application (0, 20, and 80 kg N·hm·a). The different patterns of glucose addition significantly increased soil organic C (SOC) mineralization and produced positive PE.

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As an important parameter regulating soil carbon mineralization, microbial carbon use efficiency (CUE) is essential for the understanding of carbon (C) cycle in terrestrial ecosystems. Three nitrogen supplemental levels, including control (0 kg N·hm·a), low nitrogen (40 kg N·hm·a), and high nitrogen (80 kg N·hm·a), were set up in a forest in the Daiyun Mountain. The basic physical and chemical properties, organic carbon fractions, microbial biomass, and enzyme activities of the soil surface layer (0-10 cm) were measured.

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In this paper, a reflective fiber sensing system combined with a fiber loop ringdown technique for temperature detection is proposed. A fiber Bragg grating (FBG) with an initial center wavelength of 1543.33 nm was set as the sensor head.

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G78 nitrogen deposition collector was used to investigate the background value of local nitrogen deposition flux in Daiyun Mountain National Nature Reserve of Fujian province. The results showed that dry and wet nitrogen deposition of Daiyun Mountain National Nature Reserve was 2.30 kg·hm and 14.

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Endophytic fungi were isolated from Macleaya cordata growing in Dabie Mountain by agar-block method, and then the endophytic fungi were grouped into different types based on their morphological characteristics, and thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were employed to determine whether the metabolic substances contained sanguinarine or not, and then preliminarily identified by morphological method. The results showed that the leaves hosted the largest number of endophytes (96 isolates) followed by the stems (57 isolates) and finally the roots (28 isolates), respectively. Based on morphological characteristics the endophytic fungi were grouped into 26 types in our study.

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