Hydrodynamic cavitation-assisted preparation of porous carbon from garlic peels for supercapacitors

Hydrodynamic cavitation (HC), which can effectively induce sonochemical effects, is widely considered a promising process intensification technology. In the present study, HC was successfully utilized to intensify the alkali activation of GPs for SCs, for the first time. Five BDCMs were synthesized following the method reported in the literature. For comparison, four more BDCMs with HC-treated, among which a sample was further doped with nitrogen during the HC treatment, were prepared. Then all the samples were compared from microscopical characteristics to electrochemical performance as SCs materials. The morphology study demonstrated that the HC treatment had created many defects and amorphous carbon structures on the GP-based BDCMs, with the highest SSA reaching 3272 m²/g (1:6-HCGP), which 32 folded that of the Raw carbon sample’s. The HC treatment also intensified the N-doping process. XRD and XPS results manifested that the N content had been increased and consequently changed the electronic structure of the carbon atoms, leading to the increase of specific capacitance (1:6-HCGP+N-based SC, 227 F/g at 10 A/g). The cycle performance proved that the GP-based BDCMs have long-term stability, indicating that the HC-treated BDCMs were good choices for energy storage technologies. Compared with the ultrasound-assisted method, which may have a high energy density, the HC-assisted method enables high production and energy efficiency. This work is a first time attempt towards the industrial application of HC method in energy-related materials synthesis and encourages more in-depth studies in the future.     

Sustainable extraction of ligustilide and ferulic acid from Angelicae Sinensis Radix,for antioxidant and anti-inflammatory activities

The 2030 Agenda for Sustainable Development envisions a rational use of energy and resources in all technological processes. However, in the extraction methods of compounds from medicinal plants and herbs, there is an urgent to reduce the use of organic solvents and increase the energy efficiency of these methods. Therefore, a sustainable extraction method (enzyme and ultrasonic co-assisted aqueous two-phase extraction, EUA-ATPE) of simultaneous extraction and separation of ferulic acid and ligustilide from Angelicae Sinensis Radix (ASR) was developed by integrating enzyme-assisted extraction (EAE) with ultrasonic-assisted aqueous two-phase extraction (UAE- ATPE). The effects of different enzymes, extraction temperature, pH, ultrasonic time, liquid-to-materials ratio, etc., were optimized by single-factor experiments and central composite design (CCD). Under the optimum conditions, the highest comprehensive evaluation value (CEV) and extraction yield were obtained by EUA-ATPE. Furthermore, recovery (R), partition coefficient (K), and scanning electron microscopy (SEM) analysis revealed that enzyme and ultrasonic treatment improved mass transfer diffusion and increased the degree of cell disruption. Besides, the EUA-ATPE extracts have shown great antioxidant and anti-inflammatory activity in vitro. Finally, compared to different extraction methods, EUA-ATPE achieved higher extraction efficiency and higher energy efficiency due to the synergistic effect between EAE and UAE-ATPE. Therefore, the EUA-ATPE provides a sustainable method for extracting bioactive compounds from medicinal plants and herbs, contributing to Sustainable Development Goals (SDG), including SDG-6, SDG-7, SDG-9, SDG-12, and SDG-15.     

Degradation of benzene present in wastewater using hydrodynamic cavitation in combination with air

The degradation of benzene present in wastewater using hydrodynamic cavitation (HC) alone as well as in combination with air has been studied using nozzles as cavitating device of HC reactor. Initially, the energy efficiency of the HC reactor operated at different inlet pressures was determined using the calorimetric studies. Maximum energy efficiency of 53.4% was obtained at an inlet pressure of 3.9 bar. The treatment processes were compared under adiabatic as well as isothermal conditions and it was observed that under the adiabatic condition, the extent of degradation is higher as compared to isothermal condition. Studies related to the understanding the effect of inlet pressure (range of 1.8–3.9 bar) revealed that the maximum degradation as 98.9% was obtained at 2.4 bar pressure using the individual operation of HC under adiabatic conditions and in 70 min of treatment. The combination of HC with air was investigated at different air flow rates with best results for maximum degradation of benzene achieved at air flow rate of 60 mL/sec. A novel approach of using cavitation for a limited fraction of total treatment time was also demonstrated to be beneficial in terms of the extent of degradation as well as energy requirements and cost of operation. Based on the cavitational intensity, the resonant radius of aggregates of cavitation bubbles was also determined for distilled water as well as for aqueous solution of benzene. Overall, significant benefits of using HC combined with air have been demonstrated for degradation of benzene along with fundamental understanding into cavitation effects.     

Process corner detection by skew inverters for 500 MHZ 2×VDD output buffer using 40-nm CMOS technology

A PVT detection and compensation technique is proposed to automatically adjust the slew rate of a high-speed 2×VDD output buffer. Based on the detected PVT (Process, Voltage, Temperature) corner, the output buffer will turn on different current paths correspondingly to either increase or decrease the output driving current such that the slew rate of the output signal is adaptive. The proposed design is implemented using a typical 40 nm CMOS process to justify the slew rate compensation performance. By on-silicon measurements, the data rate is 500/460 MHz given 0.9/1.8 V supply voltage with a 20 pF load. Particularly, the maximum slew rate improvement is 8%, the core area of the proposed design is 0.052×0.254 mm², the maximum slew rate is 0.53 (V/ns), and the area overhead is only 31% for one single output buffer.     

结构可靠性优化的多输出高斯过程代理模型

对于具有多失效模式的结构,基于可靠性的结构优化计算成本是比较昂贵的。本文利用多输出高斯过程MOGP(Multiple Output Gaussian Process)代理模型以降低计算成本,首先利用Bucher方法生成初始样本,然后结合均匀训练样本和学习函数对MOGP代理模型进行构建。学习函数可在大范围内筛选出较为满意的训练样本,能够确保MOGP代理模型具有较好的全局精度,在整个优化过程中不再重新构建MOGP代理模型。利用协方差矩阵,MOGP代理模型能够考虑各失效模式的相关性,对多输入多输出系统具有良好的预测性能。数值算例表明,本文方法具有较好的计算结果,且计算效率较高,尤其是设计变量数目与失效模式数目较多时效率提升明显。     

Pre-Envelope Covariance Differential Equations For White and Nonwhite Input Processes

The pre-envelope process is a complex process whose statistics are strictly related to the statistics of the envelope of a given process. The paper deals with the evaluation of the covariances of the pre-envelope output process of classically and nonclassically damped linear systems subjected to stationary and nonstationary white and nonwhite pre-envelope input process. More precisely, the pre-envelope covariances for nonwhite complex input processes are evaluated as solution of a set of first order differential equations. Furthermore, in the paper the pre-envelope of the white input process is defined, and for such input the pre-envelope covariance differential equations are determined by means of an extension to the complex field of the stochastic differential calculus. Sommario.Il processo 'pre-inviluppo' é un processo complesso i cui parametri statistici sono strettamente legati a quelli del processo 'inviluppo'. Il lavoro riguarda la valutazione delle covarianze del processo pre–inviluppo della risposta di sistemi dinamici classicamente e non classicamente smorzati soggetti a processi pre–inviluppo bianchi e filtrati, stazionari e non stazionari. Piprecisamente, nel caso di un processo filtrato pre–inviluppo le covarianze della risposta sono valutate come soluzione di un sistema di equazioni differenziali del primo ordine. Inoltre, nel lavoro definito il processo pre–inviluppo di un processo bianco e per tale caso sono presentate le equazioni differenziali delle covarianze della risposta ottenute attraverso l'estensione al campo complesso del classico calcolo differenziale stocastico.     

网络制播环境下广告节目播出的新思路

结合南京广播电视集团的实际情况,从送播流程、焊接播出和网络化下载等几个方面介绍了电视广告生产和播出上的一些新技术,对广告节目的高标清同播方式也进行了探讨。这些技术改进已实际运用在南京广播电视集团广告节目的生产播出中,并发挥了应有的作用。     

Identification and characterization of the process‐related impurities in fasudil hydrochloride by hyphenated techniques using a quality by design approach

Following the underlying principles of quality by design mentioned in the ICH Q8 guidance, systematic approaches for the control of process‐related impurities have been taken in the manufacturing process of fasudil hydrochloride, a potent Rho‐kinase inhibitor and vasodilator. Three related impurities were found in fasudil hydrochloride lab samples by a newly developed RP‐HPLC with volatile mobile phase gradient elution and UV detection method. The elemental compositions of the impurities were determined by positive ESI high‐resolution TOF‐MS analysis of their [M + H]⁺ ions and their structures were identified through the elucidation of the product mass spectra obtained by a triple quadrupole mass spectrometer. The key impurity was further verified through synthesis and organic spectroscopy including NMR and IR spectroscopy. The origins of these impurities were located and the effective approaches to eliminate them were proposed based on the redesign of the synthetic conditions. The results obtained are important for quality control in the manufacture of fasudil hydrochloride bulk drug substance and injection.     

Fries rearrangement: scalable synthesis of key fluoro building blocks 3-fluoro-4-methoxybenzoyl chloride and 1,2-diethoxy-3-fluorobenzene

Lewis acid catalyzed Fries rearrangement of 2-fluorophenyl acetate (3) was performed on kg scale. The ortho5 and para4 isomers obtained were separated in an industrially feasible way. Compound 4 was then converted into fluorinated building block 3-fluoro-4-methoxybenzoyl chloride (1) while compound 5 was converted into 1,2-diethoxy-3-fluorobenzene (2) in high yields.     

Laser direct micromilling of copper-based bioelectrode with surface microstructure array

The laser direct micromilling is proposed to fabricate the microstructure arrays on the surface of dry bioelectrodes using red copper material. Based on the principle of laser machining and SEM results, the forming process of microstructure arrays on the surface of copper-based bioelectrodes is discussed. When the process parameters are varied, the effect of process spacing, laser output power, scanning speed and number of scan on the morphology and geometrical dimension of microstructure array of bioelectrode is investigated. The results show that the cone surface microstructure can be fabricated when process spacing is set to 0.1 mm. Surface roughness of microstructure is greatly changed with different scanning speeds. The height of surface microstructure and recast layer is greatly increased with increasing laser output power. When smaller laser output power or less number of scan are selected, surface microstructure array is difficult to be fabricated. However, it is easy to generate the damage of surface microstructure when the larger output power or excessive scanning times are selected. Moreover, our developed copper-based bioelectrode shows a hydrophobic property when the spacings are selected in the range of 0.1–0.3 mm. Eventually, the optimized process parameters are obtained to fabricate the bioelectrode with cone microstructure array.