正—反—合:语文教学中的辩证思维训练

《义务教育语文课程标准(2022年版)》提出要发展学生的辩证思维。辩证思维是一种宏观看待世界的方法论,也是一种微观思考问题的方式,具有整体性与辩证性的特点。当前语文教学中的思维训练,更关注从“材料到观点”的逻辑思维发展,对辩证思维的训练不足。本文引进“正—反—合”的辩证思维方法,把它运用到文本分析、教学活动设计以及言语表达构思中,力图为语文教学中学生辩证思维的发展提供具体路径。

《史记正义》反切中“开合一致原则”的成立范围

《史记正义》反切中“开合一致原则”有其成立范围。“开合一致原则”指的是反切上字和被切字开合一致。遇摄上字既常作开口反切的切上字又常作合口反切的切上字的这一特殊性影响到原则的适用性,假设在张守节的时代模、鱼韵字拟音为开口,则“开合一致原则”对所有开口反切均成立,对绝大多数合口反切则不成立。反切创制初形成的反切用字的“呼读”传统,是造成《史记正义》中“开合一致原则”的例外反切的重要原因。

Synthesis of Sedative-hypnotic Zopiclone Analogues

Eight new cyclopyrrolone compounds were synthesized according to the structure activity relationship and action mechanism of Zopiclone, a cyclopyrrolone hypnotic. Their preliminary pharmacodynamics are under investigation.

Investigation of the coupled reaction of methyl acetate and n-hexane over HZSM-5

The coupled reaction of methyl acetate and n‐hexane was carried out over a HZSM‐5 catalyst.In addition to a thermal coupling effect,systematic variations in the product distribution were also observed in the coupled system.The bezene‐toluene‐xylene(BTX)selectivity was remarkably improved while the H2,CO,and CO2 selectivity decreased.Rapid deactivation of the catalyst was observed,caused by the extremely high reactivity of methyl acetate,which was alleviated after adding n‐hexane.These results indicated that a coupling effect exists in this system.A detailed pathway for the coupled system is suggested based on the analysis of the surface species,carbonaceous species deposited on the catalyst,as well as the product selectivity changes.The good match between the"hydrogen deficiency"of methyl acetate and the"hydrogen richness"of n‐hexane is consistent with the observed coupling effect.

A simple physical mixing method for MnO2/MnO nanocomposites with superior Zn^2+storage performance

MnO2/MnO cathode material with superior Zn^2+storage performance is prepared through a simple physical mixing method.The MnO2/MnO nanocomposite with a mixed mass ratio of 12:1 exhibits the highest specific capacity(364.2 mA·h/g at 0.2C),good cycle performance(170.4 mA·h/g after 100 cycles)and excellent rate performance(205.7 mA·h/g at 2C).Analysis of cyclic voltammetry(CV)data at various scan rates shows that both diffusioncontrolled insertion behavior and surface capacitive behavior contribute to the Zn2+storage performance of MnO2/MnO cathodes.And the capacitive behavior contributes more at high discharge rates,due to the short paths of ion diffusion and the rapid transfer of electrons.

Synthesis, characterization and catalytic application of H4SiW12O40/MCM-48 in the esterification of methacrylic acid with n-butyl alcohol

A novel environmental friendly catalyst, H4SiW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H4SiW12O40/MCM-48 was studied with methacrylic acid and n-butyl alcohol as reactants. H4SiW12O40/MCM-48 was an excellent catalyst for the synthesis of n-butyl methacrylate and Keggin structure ofH4SiW12O40 kept unchanged after impregnated on surface of the molecular sieve support. Effects of n（methacrylic acid）： n（n-butyl alcohol）, catalyst dosage, cyclohexane （water-stripped reagent） and reaction time on the yields of the product were investigated. The optimum conditions have been found, that is, molar ratio of acid to alcohol is 1：1.5, mass ratio of catalyst used to the reactant is 1.5%, cyclohexane is 10 mL and reaction time is 1.5h. Under these conditions, the yield of n-butyl methacrylate can reach 73.2%.

3D joint inversion of surface and borehole gravity data using zeroth-order minimum entropy regularization

Surface and borehole gravity data contain complementary information.Thus,the joint inversion of these two data types can help retrieve the real spatial distributions of density bodies.When a sharp boundary exists between an anomalous density body and its surrounding rock,the interface recovered by smooth inversion with Tikhonov regularization is not clear,leading to difficulties in the subsequent geological interpretation.In this work,we develop a joint inversion of surface and borehole gravity data using zeroth-order minimum entropy regularization.The method takes advantage of the complementary information from surface and borehole gravity data to enhance the imaging resolution of density bodies.It also produces a focused imaging of bodies through the zeroth-order minimum entropy regularization without requiring a preselection of a proper focusing parameter.We apply the developed joint inversion approach to three diff erent synthetic data sets.Inversion results show that the focusing inversion with the zeroth-order minimum entropy regularization provides a good description of the true spatial extent of anomalous density bodies.Meanwhile,the joint focusing inversion reconstructs a more reliable density model with a relatively high resolution when a density body is passed through by one or more boreholes.

Optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distillation

Based on a previous investigation,a simulation model was used for optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distillation.An experimental setup was established to verify the simulated results.The effects of various operating variables,such as ethanol feed location,acetic acid feed location,feed stage of reaction mixture of acetic acid and n-butanol,reflux ratio of ethyl acetate reactive distillation column,and distillate to feed ratio of n-butyl acetate column,on the ethanol/n-butanol conversions,ethyl acetate/n-butyl acetate purity,and energy consumption were investigated.The optimal results in the simulation study are as follows:ethanol feed location,15th stage;acetic acid feed location,eighth stage;feed location of reaction mixture of acetic acid and n-butanol,eighth stage;reflux ratio of ethyl acetate reactive distillation column,2.0;and distillate to feed ratio of n-butyl acetate,0.6.

Signal transduction mechanism of TRB3 in rats with non-alcoholic fatty liver disease

AIM： To evaluate the possible role of Tribble 3 （TRB3） in a rat model of non-alcoholic fatty liver disease （NAFLD） and its signal transduction mechanism.METHODS： Thirty Sprague-Dawley rats were randomized into three groups： normal control group, non-alcoholic fatty liver group A （fed on a high-fat diet for 8 wk） and group B （fed on a high-fat diet for 16 wk）. To determine the degree of hepatic steatosis in rats of each group, livers were stained with hematoxylin and eosin, and evaluated; real-time fluorescent quantitative reverse transcriptase-polymerase chain reaction was performed to measure the expression levels of TRI33 mRNA, and Western blotting analysis was done to determine the expression levels of protein kinase B （Akt） and phosphorylated protein kinase B （p-Akt-Thr308, p-Akt-Ser473）.RESULTS： Hepatic steatosis was evident in both NAFLD groups： mild to moderate hepatic steatosis occurred in group A, mainly as mild steatosis.Moderate to severe hepatic steatosis occurred in group B, mainly as severe steatosis. The expression level of TRB3 mRNA in group B was significantly higher than in the control group （122.28 ± 95.37 vs 3.06 ± 2.33,P = 0.002） and group A （122.28 ± 95.37 vs 5.77 ± 4.20,P = 0.001）. There was no significant difference in the expression levels of Akt （1.03 ± 0.53 vs 1.12 ± 0.77,P = 0.729） and p-Akt-Thr308 （0.82 ± 0.45 vs 0.92 ± 0.38, P = 0.592） between group A and the control group. The expression level of Akt and p-Akt-Thr308 in group B was significantly lower than in group A （Akt 0.41 ± 0.16 vs 1.12 ± 0.77, P = 0.008; p-Akt-Thr308 0.47 ± 0.19 vs 0.82 ± 0.45, P = 0.036） and the control group （Akt 0.41 ± 0.16 vs 1.03 ± 0.53, P = 0.018;p-Akt-Thr308 0.47 ± 0.19 vs 0.92 ± 0.38, P = 0.010）.The expression level of p-Akt-Ser473 in group A was significantly higher than in group B （1.48 ± 0.50 vs 0.81± 0.39, P = 0.041） as well as the control group （1.48 ± 0.50 vs 0.45 ± 0.26, P = 0.003）.CONCLUSION： TRB3 blocks insulin signaling by inhibiting Akt activation, which contributes to insulin resistance. It may be an important factor in the occurrence and development of NAFLD.

Control mechanism for the upper airway collapse in patients with obstructive sleep apnea syndrome: a finite element study

Obstructive sleep apnea syndrome (OSAS) is characterized by recurrent collapses of the upper airway, which lead to repetitive transient hypoxia, arousals and finally sleep fragmentation. Both anatomical and neuromuscular factors may play key roles in the pathophysiology of OSAS. The purpose of this paper was to study the control mechanism of OSAS from the mechanical point of view. A three-dimensional finite element model was developed, which not only reconstructed the realistic anatomical structure of the human upper airway, but also included surrounding structures such as the skull, neck, hyoid, cartilage and soft tissues. The respiration process during the normal and apnea states was simulated with the fluid-structure interaction method (FSI) and the computational fluid dynamics method (CFD). The airflow and deformation of the upper airway obtained from the FSI and the CFD method were compared and the results obtained under large negative pressure during an apnea episode were analyzed. The simulation results show that the FSI method is more feasible and effective than the CFD method. The concave configuration of the upper airway may accelerate the collapse of the upper airway in a positive feedback mechanism, which supplies meaningful information for clinical treatment and further research of OSAS.

An accurate,high-speed,portable bifunctional electrical detector for COVID-19

Coronavirus disease 2019(COVID-19),caused by SARS-CoV-2,has rapidly spread and caused a severe global pandemic.Because no specific drugs are available for COVID-19 and few vaccines are available for SARS-CoV-2,accurate and rapid diagnosis of COVID-19 has been the most crucial measure to control this pandemic.Here,we developed a portable bifunctional electrical detector based on graphene fieldeffect transistors for SARS-CoV-2 through either nucleic acid hybridization or antigen-antibody protein interaction,with ultra-low limits of detection of~0.1 and~1 fg mL^(−1) in phosphate buffer saline,respectively.We validated our method by assessment of RNA extracts from the oropharyngeal swabs of ten COVID-19 patients and eight healthy subjects,and the IgM/IgG antibodies from serum specimens of six COVID-19 patients and three healthy subjects.Here we show that the diagnostic results are in excellent agreement with the findings of polymerase chain reaction-based optical methods;they also exhibit rapid detection speed(~10 min for nucleic acid detection and~5 min for immunoassay).Therefore,our assay provides an efficient,accurate tool for high-throughput point-of-care testing.