Efficient defect passivation for high performance perovskite solar cell by adding alizarin red S

Planar perovskite solar cells (PSCs) have excellent photoelectric properties and show great commercialization potential. However, there are a lot of crystal defects in the perovskite films prepared by solution method, which reduces the development process of solar cells. In this work, alizarin red s (ARS) was doped into MAPbI₃ films to passivate the defect. It was shown that the addition of ARS increased the quality of perovskite film and doped perovskite film exhibited improved light absorption. In addition, it was found that there was a strong interaction between ARS and perovskite, which reduced the density of defect states. The results showed that the passivated perovskite device had improved PL intensity, increased carrier lifetimes and reduced charge recombination. After passivation, the device obtained a higher open-circuit voltage (V_OC) of 1.103 V where the control device was 1.055 V, and the best power conversion efficiency (PCE) of the doped device was 18.82%, which is 11.36% higher than that of the control device of 16.90%.

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Control system design of hybrid fuel cell city bus

This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrogen storage and delivery system, the hydrogen leakage alarm system were developed. The real-time distributed control and diagnosis system based on the Time Trigger Controller Area Network (TTCAN) with 10 ms basic control period was developed. The concept and implementation of processor (or controller) monitor and process (or task) monitor technique based on the TTCAN were applied in this paper. The fault tolerant control algorithm of the fuel cell engine and the battery management system were considered. The demonstration experience verified that the fault tolerant control was very important for the fuel cell city bus.     

Nondestructive measurement of soluble solid content of navel orange fruit by visible-NIR spectrometric technique with PLSR and PCA-BPNN

A relationship was established between the soluble solid content (SSC) of navel orange fruit determined by destructive measurement and visible-near infrared diffuse reflectance spectra in the wavelength range of 350-1800 nm. Multiplicative scatter correction (MSC) and standard normal variate correction (SNV) were applied to the spectra, partial least squares regression (PLSR) and back propagation neural network (BPNN) based on principal component analysis (PCA) were used to develop the models for predicting the SSC of intact navel orange fruit. Thirty-eight unknown samples were used to evaluate the performance of these models. The principal component analysis-back propagation (PCA-BPNN) method with MSC spectral pretreatment obtain the best predictive results, resulting in correlation coefficient, root mean square error of prediction (RMSEP), average difference between predicted and measured values (Bias) of 0.90, 0.68 °Brix and 0.16 °Brix, respectively. Experimental results indicate that PCA-BPNN is a suitable tool to model the non-linear complex system, with additional advantages over PLSR, and the vis/NIR spectrometric technique can be used for measuring the SSC of intact navel orange fruit, nondestructively.     

Green and Effective Ammonium Carbonate-assisted Process for Drying Hemicellulose Obtained through Alkali Extraction of Bleached Bamboo Kraft Pulp

Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp fibers.Due to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is challenging.In this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction process.Hemicellulose obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying process.The effects of drying time and drying temperature were determined.Structure of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction analyses.The novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of hemicellulose.The dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films.     

FZ/T 73023-2006《抗菌针织品》行业标准的编制过程、背景及相关参数的确定

简述了FZ／T 73023-2006《抗菌针织品》行业标准的编制过程及编制背景；结合该标准相关参数的确定过程，简要介绍了国内外纺织品抗菌性能测试方法的现状，以及抗菌纺织品的安全性要求；围绕维护人体皮肤微生态平衡的要求，简要阐明了该标准的先进性及创新性。     

Determination of Amino Acid Nitrogen in Soy Sauce Using Near Infrared Spectroscopy Combined with Characteristic Variables Selection and Extreme Learning Machine

Amino acid nitrogen (AAN) is one of the most important indicators to assess the quality grade of soy sauce in China. Near infrared (NIR) spectroscopy technique combined with characteristic variable selection and extreme learning machine (ELM) was applied to detect AAN content in soy sauce in this work. First, the optimal spectral intervals were selected by synergy interval partial least square. Then, ELM model based on the optimal spectral intervals was established, called synergy interval extreme learning machine (Si-ELM) model. Support vector machine model based on the optimal intervals was established comparatively. These models were optimized by cross validation, and the performance of each final model was evaluated according to correlation coefficient ( $ R_{\text{p}}^2 $ ) and root mean square error of prediction (RMSEP) in prediction set. Si-ELM showed excellent performance. The best Si-ELM model was achieved with $ R_{\text{p}}^2 = 0.9657 $ and RMSEP?=?0.0371 in the prediction set. It was concluded that NIR spectroscopy combined with Si-ELM was an appropriate method to detect AAN content in soy sauce.     

Evaluation of chicken freshness using a low-cost colorimetric sensor array with AdaBoost–OLDA classification algorithm

This paper attempted to evaluate chicken freshness using a low-cost colorimetric sensor array with the help of a classification algorithm. We fabricated a novel and low-cost colorimetric sensors array, with a specific colorific fingerprint to volatile compounds, using printing chemically responsive dyes on a C2 reverse silica-gel flat plate. In addition, we proposed a novel classification algorithm for sensors data classification – orthogonal linear discriminant analysis (OLDA) and adaptive boosting (AdaBoost) algorithm, namely AdaBoost–OLDA. And we compared it with two classical classification algorithms – linear discriminant analysis (LDA) and back propagation artificial neural network (BP-ANN). Experimental results showed classification results by AdaBoost–OLDA algorithm is superior to BP-ANN and LDA algorithms, the classification results by which are both 100% in the calibration and prediction sets. This study sufficiently demonstrated that the colorimetric sensors array with a classification algorithm has a high potential in evaluating chicken freshness, and AdaBoost–OLDA algorithm has a strong performance in solution to a complex data classification.     

皮蛋加工腌制粉的研究

本研究选用两批共10组配方的皮蛋粉,通过对各组加水搅拌料泥后部分性质的比较,以及选用新鲜完好的鸭蛋为原料,滚蛋、密封保存,通过对其定期抽样检测及皮蛋成品的质量检测,确认第二批第四组配方较为理想,用该粉剂做成的皮蛋成品香、味俱佳,碱Cu、Zn的含量均符合国家标准,是一种方便城乡居民的产品.     

不同溶剂提取花椒精油的试验研究

采用无水乙醇、乙醚、丙酮及水作溶剂，对四川汉源花椒作了精油提取研究。并用GC-MS分析和鉴定了花椒精油中的主要化学成分。试验结果发现，用有机溶剂提取的花椒精油，主要化学成分基本相同，且包含了用水作溶剂提取的花椒精油中的主要化学成分。几种有机溶剂中，又以乙醚的提取性能最好。     

复合微生物的筛选及其发酵秸秆的应用效果

为提高秸秆的发酵效果,通过筛选纤维素酶活力和木聚糖酶活力高的一定比例的复合菌株,并进行秸秆复合菌株发酵应用研究。结果表明,最佳复合菌株为：白腐菌+黑曲霉+米曲霉+芽孢杆菌+放线菌（1∶1∶1∶1∶1）,其纤维素酶活最高值为203.64 U/g,木聚糖酶活最高值为10 017.41 U/g。发酵田间大堆小麦秸秆时,试验组发酵38 d的秸秆,中性洗涤纤维、粗纤维比发酵前显著降低（P＜0.05）,粗蛋白显著升高（P＜0.05）。与对照组发酵38 d的秸秆相比,中性洗涤纤维显著降低（P＜0.05）,粗蛋白显著升高（P＜0.05）。发酵过程中温度有高温期、中温期和低温期,发酵结束时秸秆pH值（7.73）为微碱性,符合发酵堆肥标准。发酵结束后试验组的秸秆比对照组的秸秆腐化程度高。因此,混菌发酵有助于提高秸秆的发酵效果。