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[Introduction] Lithium-ion battery has become the most widely used new energy storage technology. However, it is found that the practical service conditions have great impacts on the actual service behaviors of lithium-ion battery energy storage. This paper aims to study the influence of service conditions on the electrochemical performance of lithium-ion battery, so as to provide references for the construction of future lithium-ion battery energy storage projects. [Method] The effects of operating charge interval, discharge rate and operating temperature on the actual performance of Li-ion battery were tested and analyzed. [Result] The working SOC range, charge/discharge rage and operating temperature all have great influence on the actual performance of lithium-ion battery. On the one hand, proper adjustment of charge and discharge range can significantly improve the service life. On the other hand, the current commonly used 2 C configuration mode may significantly reduce the service life, while reducing the rete configuration to 1 C is expected to achieve lower levelized cost of energy although it will increase the initial investment. In addition, temperature control is extremely important to the usage of lithium-ion batteries, even single-digit temperature differences can cause significant battery inconformity over long cycle life. [Conclusion] Lithium-ion battery energy storage with advantages of fast response speed, high adjustment accuracy and flexible configuration will further play an important role in the work of "carbon peak and neutrality" and the gradual construction of the power market. Paying attention to the influence of practical conditions on the performance of lithium-ion battery will further improve the use efficiency of lithium-ion battery energy storage. In summary, the design of the battery working condition according to the demand of the practical application can provide lithium-ion battery energy storage system more excellent performance, and play an important role to realize the "carbon peak and neutrality" goal of our country.

The solid-fermented process conditions of producing feruloylated oligosaccharides (FOs) from corn bran were optimized in this study. The fungus Neurospora sitophila (generally recognised as safe, GRAS) was used as fermenting species, and FOs content was considered as the indicator, the single-factor and response surface experiments were performed to optimize the culture medium and culture conditions, including inoculation amount, fermentation time, fermentation temperature, and added amount of water. An FOs yield of 1.52 μmol/g was achieved under the following conditions: 5 g of corn bran and 2% of corn bran weight (w/w) of soybean meal in a 250 mL conical flask, an inoculation size of 1.17×105 spores/flask, a fermentation time of 75 h, a fermentation temperature of 28 ℃, and added water mount of 15.2 mL. The observed yield value was close to the theoretical value predicted by the model (1.56 μmol/g), and increased by 60.83% compared with that of the pre-optimized process. Therefore, the FOs content of the product significantly increased by the optimization of the fermentation process, which offered a novel thought for enhancing the added value and expanding the routes for preparing maize bran-derived FOs.

[Introduction] In order to guarantee urban power supply and offshore wind power utilization without building new power lines, the paper aims to establish a electricity transmission strategy based on wind-coal-battery- hydrogen -CCUS multi energy coupling and bundling system, which is analyzed theoretically and verified by simulation.[Method] To verify the effectiveness of the strategy, four experimental schemes (separate transmission of wind and coal power, bundled transmission of wind and coal power without operation coupling, bundled transmission of wind and coal power with operation coupling, and wind-coal-battery-hydrogen-CCUS coupled transmission) were set up, and based on the HOMER software environment and particle swarm optimization algorithm, the system operation simulation and index calculation of the test scheme are carried out.[Result] According to the simulation results, compared with normal separate transmission strategy, power transmission line capacity of system applying wind-coal bundled transmission strategy can be decreased by 2.2 GW, with an average utilization rate of 59%, i.e. 21%~23% higher. In the case that the wind power and coal power share the same transmission line without coordinated operation, the wind power curtailment is 164 GWh in total. System applying wind-coal-battery–hydrogen-CCUS bundled transmission strategy could avoid wind power curtailment and reduce carbon emission from unit power supply by about 30~33g/MWh. [Conclusion] In conclusion, the electricity transmission strategy established by this paper is supposed to be feasible and effective and contributing to planning and construction of offshore wind power project.

Objective To evaluate the effects of remimazolam versus propofol on the quality of postoperative recovery in patients undergoing vocal cord polypectomy with supportive laryngoscopy by the 15-item quality of recovery scale (QoR-15). Methods A total of 90 patients who underwent vocal cord polypectomy with supported laryngoscopy from the Fourth Clinical College of Xinxiang Medical University from December 2022 to October 2023 were divided into remimazolam combined with mivacurium group (group R) and propofol combined with mivacurium group (group P) by random block design method, with 45 cases in each group. By intravenous administration, patients in group R and group P were given remiazolam 0.2 to 0.3 mg/kg and propofol 1.5 to 2.0 mg/kg, respectively. After the disappearance of eyelash reflex, sufentanil 0.3 g/kg and mivacurium 0.25 mg/kg were given to all patients. The quality of postoperative recovery was evaluated by the QoR-15 scale 1 day before, 1 day and 2 days after surgery. Mean arterial pressure, heart rate, pulse oxygen saturation, and Modified Observers Assessment of Alertness/Sedation Scale (MOAA/S) scores of the two groups were recorded at different time points. The time required including surgery, recovery of spontaneous breathing, endotracheal tube removal, and post anesthesia care unit (PACU) stay after surgery,and the occurrence of intra- and post-operative adverse reactions were recorded. Results The QoR-15 scale score of group R was lower than that of group P (P＜0.05) on the first day after surgery, but it was not clinically significant because the minimum clinically significant change value of QoR-15 scale score was 6 points. The recovery time of spontaneous breathing and extubation time in group R were longer than those in group P (P＜0.05), but there was no significant difference in PACU stay time between the two groups (P＞0.05). The incidences of hypotension and injection site pain in group R were lower than those in group P (24.4% vs 64.4%, χ2=14.580, P＜0.01; 6.7% vs 84.4%, χ2=54.878, P＜0.01), and no significant difference was found in the incidence of other adverse reactions (P＞0.05). ConclusionIn the anesthesia of vocal cord polypectomy under supported laryngoscopy, the quality of patients recovery using remimazolam is comparable to that of propofol. While meeting perioperative needs, it can maintain more stable hemodynamics, without significant injection site pain, and can improve perioperative patients comfort."

Several common models for carbon prediction were discussed based on an off-gas analysis of the basic oxygen furnace (BOF) process, and the basic principles, advantages and disadvantages of three exponential decay models with different correction algorithm were analyzed respectively. An improved exponential model of “critical carbon content fitting + update curves simultaneously” algorithm was established by combining the advantages of previous algorithms. Firstly, the historical decarburization curve in the end blowing stage and the critical carbon content in the bath were obtained by exponentially fitting the decarburization data of historical heats. Secondly, the reference decarburization curve was obtained by replacing the corresponding parameter of the historical decarburization curve with the maximum specific decarburization rate in the middle blowing stage of the real-time heat. Subsequently, the specific decarburization rates of the historical decarburization curve and the reference decarburization curve were converted to dimensionless values within the range of 0 to 1 by normalizing. Then, a multi-point correction method was used to correct the calculation results of the carbon content in the bath and repeatedly modify the key parameters of the calculated decarburization curve, according to the deviation of the removed carbon amount between the normalized reference curve and the actual process. The key parameters of the calculated and the reference decarburization curves were updated simultaneously after each calculation step, and the calculation error of the carbon content prediction decreased gradually through iterative calculation. Finally, the carbon content in the bath were precisely predicted in the end blowing stage of the BOF process. Plant trials were carried out in a BOF converter to demonstrate the performance of the proposed models. The results show that the new model exhibits better adaptability and higher accuracy than the other ones. The hit ratio of the new model to predict the end-point carbon content reaches 90% within a tolerance of ±0.02%.

The widespread and frequent use of antibiotics to treat diseases or encourage animal growth has resulted in their persistence and accumulation in water, soil, and sediments. As a typical emerging pollutant in the environment, antibiotics have become an important research focus in recent years. Antibiotics are commonly found at trace levels in water environments. Unfortunately, the determination of various types of antibiotics, all of which exhibit different physicochemical properties, remains a challenging endeavor. Thus, developing pretreatment and analytical techniques to achieve the rapid, sensitive, and accurate analysis of these emerging contaminants in various water samples is an essential undertaking.In this paper, a solid phase extraction-high performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS) method for the simultaneous determination of 22 antibiotics including 4 penicillins, 12 quinolones and 6 macrolides in environmental water samples was developed. Based on the characteristics of the screened antibiotics and sample matrix, the pretreatment method was optimized, focusing on the SPE column, pH of the water sample, and amount of ethylene diamine tetra-acetic acid disodium (Na 2 EDTA) added to the water sample. Prior to extraction, a 200 mL water sample was added with 0.5 g of Na 2 EDTA and pH-adjusted to 3 using sulfuric acid or sodium hydroxide solution. Water sample enrichment and purification were achieved using an HLB column. HPLC separation was carried out on a C 18 column (100 mm×2.1 mm, 3.5 μm) via gradient elution with a mobile phase composed of acetonitrile and 0.15% (v/v) formic acid aqueous solution. Qualitative and quantitative analyses were performed on a triple quadrupole mass spectrometer in multiple reaction monitoring mode using an electrospray ionization source. The results showed correlation coefficients greater than 0.995, indicating good linear relationships. The method detection limits (MDLs) and limits of quantification (LOQs) were in the ranges of 2.3-10.7 ng/L and 9.2-42.8 ng/L, respectively. The recoveries of target compounds in surface water at three spiked levels ranged from 61.2% to 157%, with relative standard deviations (RSDs) of 1.0%-21.9%. The recoveries of target compounds in wastewater at three spiked levels were 50.1%-129%, with RSDs of 1.2%-16.9%. The method was successfully applied to the simultaneous determination of antibiotics in reservoir water, surface water, sewage treatment plant outfall, and livestock wastewater. Most of the antibiotics were detected in watershed and livestock wastewater. Lincomycin was detected in 10 surface water samples, with a detection frequency of 90%, and ofloxacin showed the highest contents (127 ng/L) in livestock wastewater. Therefore, the present method exhibits excellent performance in terms of MDLs and recoveries compared with previously reported methods. The developed method presents the advantages of small water sample volumes, wide applicability, and fast analysis times; thus, it can be considered a rapid, efficient, and sensitive analytical method with excellent potential for monitoring emergency environmental pollution. The method could also provide a reliable reference for formulating antibiotic residue standards. The results provide strong support for and an improved understanding of the environmental occurrence, treatment, and control of emerging pollutants.

Purpose: This study aimed to assess the diagnostic efficacy of contrast-enhanced CT in the screening of extracapsular spread by head and neck cancers., Methods: Electronic databases, including MEDLINE, EMBASE,CBM,CNKI and SciencePaper Online were searched electronically. Hand-searching was also performed. QUADAS-2 was used by two independent reviewers to assess the methodological quality, and data extraction of included studies was delivered. Meta analysis was conducted via MetaDisc1.4 and STATA 11.0., Results: A total of 8 studies involving 639 participants were included. All studies were retrospective, 1 had high risk of bias, and the remaining had unclear risk of bias. Meta analysis showed that when screening extracapsular spread, contrast-enhanced CT had a pooled sensitivity of 0.67, pooled specificity of 0.84, area under curve of 0.83., Conclusions: Contrast-enhanced CT is a good tool for diagnosing extracapsular spread by head and neck cancers.

Samples were dissolved using nitric acid, perchloride acid and hydrofluoride acid in the medium of 0.025 mol x L(-1) EDTA with a kind of standard solutions, and the element contents of Ni, Cu, V, Mn, W, Mo, Co and Cr were determined by ICP-AES method. After investigating the spectral interfere from matrix element and coexistent elements, optimum spectral lines were selected for each analyzed element, and the analytical precision, detection limits and recoveries were measured. The results show that the detection limits of the method are very low, relative standard deviations (n=10) are less than 1%, and the recoveries range from 98.2% to 101.6%. The proposed method is accurate, reliable, simple, and rapid. The method satisfies.

Spectrophotometric simultaneous determination of phenol and resorcinol was studied. The absorption spectra of these two components severely overlap in ultraviolet spectral range. In the wavelength range of 250-290 nm, the absorbances of phenol and resorcinol were measured with an internal of 0.5 nm. Two wavelengths at 280.5 and 273.5 nm were chosen for the determination. Dual-wavelength linear regression method was used for the determination of phenol and resorcinol. Twenty five mixture standard solutions were prepared according to the orthogonal projection form L25 (5(6)). Two kinds of the components were linearly regressed. Meanwhile the contents of phenol and resorcinol in six synthetic mixture samples and simulation pharmaceutical preparations were measured. The measurement results showed that the relative error of phenol and resorcinol were less than 5%. The measurement system is stable and reliable. Therefore, the dual-wavelength spectrophotometric linear regression method may provide a new approach to the determintion of phenol and resorcinol in their compound preparations.

The complex reaction of ruthenium with 1,10-phenanthroline was studied. In the medium of pH 5 HAc-NaAc buffer and NH2OH * HCl solution, ruthenium reacts with 1,10-phenanthroline to form a 1 : 3 complex by heating in a boiling water bath for 5 min. The fluorescence peak excitation wavelength is 448 nm, and the emission peak wavelength is 586 nm. The linear relation between fluorescence intensity and the concentration of Ru(II) was found to be 0-10 microg x 25 mL(-1). The ruthenium in the sample was separated by distill. The method has been used to the determination of ruthenium in anode slime of alkali chloride factory with satisfactory results.

By means of artificial neural network and Levenberg Marquardt Back Propagation (LM-BP) train algorithm, the three components of pyrocatechol, resorcinol and hydroquinone were determined simultaneously. The absorption spectra of these three components severely overlap in ultraviolet spectral range. Three wavelengths at 283.5, 279.5 and 276.5 nm were selected for the determination. 25 mixture standard solutions were prepared according to orthogonal projection form L25 (5(6)). Three kinds of components were trained. Mean Squared Error (MSE) reaching minimum value is 0.083 114 3. Meanwhile the contents of pyrocatechol, resorcinol and hydroquinone in six simulation mixture samples were predicted. The relative errors of the three kinds of components were slightly larger under the low concentration condition, and the mean relative error for most analytical results was less than 5%, especially it is satisfactory for the analytical results of pyrocatechol and resorcinol with severely overlapped absorption spectra.

The contents of four microamount elements (Sr, Cu, Mg and Zn) in human blood were chosen as recognition index of coronary heart disease patients and normal persons. The recognition pattern of Levenberg-Marquardt Backpropagation algorithm has been established. The first-layer transfer function is Tansig function; the second-layer transfer function is linear Purelin function. There are four input vectors, eight neurons on hidden layer, and one neuron of output vector. Four samples were chosen as a teat group and 22 samples as a training group. The weights and biases of the neural network were given. The given data could be completely identified, which predicted that this method could be a supplementary tool to diagnose this kind of disease with the determined contents of microamount of elements in human blood.

Gd2O3: Eu nanocrystal was synthesized by EDTA complexing sol-gel process at relatively low temperature, in which ethylene-diamine-tetraacetic acid (EDTA) and polyethylene glycol (PEG) were used as the chelating agent and disperser respectively. The properties of the nanocrystal were investigated by XRD, SEM, EDS, and fluorescence spectrophotometer. The results show that nanosized, homogenous and pure cubic phase Gd2O3: Eu has been produced after the precursor calcined at 800 degrees C for 2 h. The particles of the Gd2O3: Eu are basically spherical in shape and about 30 nm in size. The main emission peak of Gd2O3: Eu nanocrystal is at 611 nm, resulting in a red emission. Compared with micron scale Gd2O3: Eu phosphors prepared by a conventional method, a clear red shift occurs in the excitation spectrum of Gd2O3: Eu nanocrystal prepared by the present work, and the quenching concentration of Eu has been raised. For this type of nanophosphor, quenching starts at an Eu concentration of 8% (mol%), while a value of 6% was obtained for the conventional one.

The determination of phosphorus with crystal violet-heteropoly molybdophosphoric acid in the presence of starch has been studied. In the medium of 0.15 mol.L-1 H2SO4, the apparent molar absorptivity of the ion associated complex is 1.98 x 10(5) L.cm-1.mol-1 at 548 nm, and it is stable for more than 24 hours. Beer's law is obeyed over the range of 0-8 micrograms.(50 mL)-1 for phosphorus. The molar ratio of heteropoly molybdophosphoric acid to crystal violet is established to be 1:5. The method is satisfactory for the determination of phosphorus in iron basic samples.