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Human activities lead to an increase in greenhouse gases in the environment, among which carbon dioxide (CO2) is one of the most prominent, giving rise to global warming and climate change. Climate change, along with the resulting environmental degradation, is one of the most challenging difficulties faced by humanity in the twenty-first century. The forest ecosystem, with plants being its most important component, plays a pivotal role in regulating climate. Carbon sequestration and oxygen release (CSOR) by plants are major ecological service functions that play an important role in mitigating the negative impacts of the greenhouse effect and help to achieve carbon peaking and neutrality. The CSOR of mulberry (Morus spp.), a species of economic and ecological significance, is not yet understood. Six mulberry tree varieties were selected to evaluate their CSOR potential during summer. We took into consideration whole-plant diurnal assimilation amounts (P), carbon sequestration per unit leaf area (WCO2), oxygen release per unit leaf area (WO2), carbon sequestration per unit land area (PCO2), and oxygen release per unit land area (PO2). Zhongsang 1302 showed the greatest potential for CSOR among the six mulberry varieties. The PCO2 value of the Zhongsang 1302 variety was 1531.84 g·m−2 during summer, followed by Suhu 16 (1380.12 g·m−2), Husang 32 (1005.63 g·m−2), Zhongsang 9703 (990.01 g·m−2), Yu 711 (940.43 g·m−2), and Jin 10 (848.29 g·m−2). Moreover, the Pearson correlation and path analyses showed that photosynthetic rate (PN) and leaf area index (LAI) mainly affect the overall CSOR potential in mulberry. These findings not only enrich theoretical research on CSOR in mulberry, but also serve as an important reference for the use of different mulberry tree varieties in improving climate conditions and achieving carbon peaking and neutrality. [ABSTRACT FROM AUTHOR]

One of the main challenges most organic photodiodes (OPDs) facing is to overcome the traditional trade‐off between ultralow dark current and high responsivity (R) in existing research. Here, van der Waals multilayer OPD based on water transfer printing method, termed hybrid bulk‐heterojunction (BHJ)/planar‐heterojunction (PHJ) (B‐PHJ) framework, is constructed making certain the high‐quality interface and novel two‐phase energy band alignment between the active and barrier layer with noise suppression and photovoltaic complement simultaneously. The prepared OPD exhibits the combined advantages of ultralow dark current (0.2 nA cm−2 at −1 V) and high responsivity (0.49 A W−1 at 850 nm). As a result, these superimposed effects enable the device to feature a superior liner dynamic range (LDR) of 210 dB and a specific detectivity of 1014 Jones to address the conventional responsivity‐noise trade‐off. The results reveal that the balance dynamics of charge transfer and charge blocking in van der Waals hybrid two‐phase framework OPD, may inspire the development of next OPDs. Finally, its diverse practical application potential is demonstrated through long‐distance misaligned photoplethysmography (PPG) measurement. [ABSTRACT FROM AUTHOR]

2D materials provide an effective strategy for the construction of fast‐responsive and highly sensitive Schottky heterojunction devices. However, the strong Fermi pinning at the contact between bulk metallic electrodes and 2D semiconductor materials greatly hinders the wide application of such devices in optoelectronics. Herein, a self‐powered photodetector with high performance is fabricated based on an all‐2D van der Waals (vdWs) heterojunction composed of metallic 2H‐NbSe2 and semiconducting MoSe2. Benefiting from the strong built‐in electric field, the device exhibits a high rectification ratio of 2.1 × 103. Furthermore, the photovoltaic effect can be observed in a broad spectrum ranging from 405 to 980 nm without external voltage, where a maximum responsivity of 64.92 A W−1, a maximum specific detectivity of 2.39 × 1014 Jones, and a large on–off current ratio >105 are obtained at 650 nm. Simultaneously, the efficient charge separation at the high‐quality heterointerface of NbSe2/MoSe2 results in a fast response/recovery time of 180/80 µs. This work demonstrates the promising potential of the 2D metallic NbSe2 as an electrode forming a Schottky heterojunction to realize a high‐performance broadband photodetector for near‐infrared communication. [ABSTRACT FROM AUTHOR]

Quantitative analyses of synthetic polymers were accomplished using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS). Many factors have hindered the development of quantitative measurement of polymers via MALDI TOF MS, e.g., laser power, matrix, cation salt, and cocrystallization. By probing the optimal conditions, two sets of polymers were studied. Fair repeatability of the samples ensures acceptable results. In set 1, two poly(ethylene glycols) with different end groups showed equal desorption/ionization efficiencies. Two synthetic polymers in set 2 with different chemical properties resulted in different MALDI responses. Good linearity was achieved by plotting the relationship between the sample concentration ratio and the total signal intensity ratio in both sets.

An analytical method based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been applied to provide information on the structure of a copolymer, e.g., repeat unit and end group. Seven conjugated polymers, which have been demonstrated as the active component in blue light-emitting diodes, were synthesized through Suzuki poly-condensation reaction in the presence of Pd[(P[Ph.sub.3]).sub.4] catalyst. Their molecular weights were obtained using gel permeation chromatography analysis. MALDI-TOF MS was used to investigate the structure information in detail. The proposed end-group structures were confirmed by the identity between the observed and the simulated isotopic distribution of each polymer. The results demonstrate that these synthetic polymers possess various end groups and even contain macrocycles. The catalyst Pd[(P[Ph.sub.3]).sub.4] was found to introduce phenyl end groups via aryl-aryl exchange between the catalytic palladium intermediate and the triphenylphosphine ligand. All these results are based on the analysis of the mass spectrum data, which suggests that MALDI-TOF MS is an extraordinarily strong tool in synthetic polymer structure analysis.

This paper describes experience with the sequencing of synthetic segment peptides of gp41 which are used in trimeric peptides as potential peptide-based vaccines and as inhibitors to mimic the fusion state of gp41 in HIV infection using ESI/CID-FT-ICR MS. All b and y″ series ions are found in the CID spectra and the mass difference between the calculated and observed results is very slight. FT-ICR MS again shows its power in peptide sequencing, successfully helping us obtain the sequence of an unknown peptide. [ABSTRACT FROM AUTHOR]