Deep eutectic solvents and alkaline extraction of protein from seabuckthorn seed meal: a comparison study

Seabuckthorn seed meal(SSM) is a waste of oil extraction industry that rich in protein. In order to seek suitable protein extraction method, three different deep eutectic solvents(DESs)(including choline chlorideglycerol, choline chloride-oxalic acid and choline chloride-urea) were developed for extracting protein from SSM and compared with alkaline. Result indicated that alkaline could effectively extract 56.9% protein from SSM and its protein content was 73.1%, higher than DES at 31.0%-41.4% and 64.3%-67.5%, respectively. However, compared to alkali, DES led to a product with less β-sheet, more β-turn, more essential amino acids, higher total amino acid content, especially choline chloride-urea which extracted protein showing an integrated and similar protein weight distribution compared to SSM. Also, this protein extracted chloride-urea showed a highest digestibility in vitro(by pepsin)(54.2%). These results indicated that choline chloride-urea extraction is better than alkaline extraction for SSM.

Synchrophasor-based Online State Estimated in Large-scale Power Grid

With integration of a larger amount of clean power sources and power electronic equipment,operation and dynamic characteristics of the power grid are becoming more and more complicated and stochastic.Therefore,it is necessary and urgent to obtain accurate real-time states,which is difficult from traditional state estimation.This paper systematically develops a phasor measurement unit(PMU)based real-time state estimator for a realistic large-scale power grid for the first time.The estimator mainly relies on three refined algorithms,i.e.,an improved linear state estimation algorithm,a practical bad data identification method and a distributed topology check technique.Furthermore,a novel system architecture is designed and implemented for the China Southern Power Grid.Numerical simulations and extensive field operation results of the state estimator recorded under both normal and abnormal situations are presented.All the tests and field results demonstrate the advantages of the proposed algorithms in terms of online system monitoring and feasibility of refreshing the states of the whole system at intervals of tens of milliseconds.

Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of attention.In this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control gate.We demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 ps.The current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

Drying-rewetting rather than sieving stimulates soil respiration

Dear Editor,Soils contain the largest carbon(C) pool in terrestrial ecosystems.Even a small change in soil C pool may significantly influence atmospheric carbon dioxide(CO_(2)) concentration.Thus,it is critical to accurately assess the response of soil C pool to global change.Soil incubation is a frequently used method to assess soil C decomposition rate because it allows environmental variables to be under control(Unger et al.,2010;Shi and Marschner,2014).However,pre-treatments during soil sampling and processing,such as sieving and drying-rewetting,inevitably bring physical disturbances which may affect soil respiration rate(Franzluebbers,1999;Thomson et al.,2010;Curtin et al.,2014).