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A highly reducing conjugated porous polymer enables pinacol C–C coupling with superior performance in a metal-free and recyclable fashion under visible light.

Studies show that manganese sulfide (MnS) inclusions in pipeline steel affect the lateral performance of steel in its rolling deformation, as well as the hydrogen-induced cracking and sulfide stress corrosion cracking resistance performance. To inhibit the precipitation of MnS and its effect on pipeline steel, a quenching experiment and a diffusion couple experiment, which investigated the evolution of MnS inclusions in Ti-bearing X80 pipeline steel, were conducted. The experimental results show that the transformation of the MnS inclusions during solidification is as follows: MnS→titanium sulfide (TiS)→Ti4C2S2. The transition temperatures of MnS to TiS and TiS to Ti4C2S2 are 1673 and 1273 K, respectively, and the overall size of the sulfide decreased as well. Thermodynamic calculation results confirm that the transition temperatures of MnS to TiS and TiS to Ti4C2S2 are 1623 and 1203 K, respectively. When the sulfur content in the X80 pipeline steel is 0.001 5%, all the sulfur in the steel can be converted into Ti4C2S2 with a titanium content of more than 0.02%.

A mathematical model was developed to investigate the effect of snorkel shape on the recirculation rate and the erosion of the lining refractory during RH degassing process. A particle image veloci...

To clarify the influence of FeO and sulfur on solid state reaction between an Fe−Mn−Si alloy and MnO−SiO2−FeO oxides under the restricted oxygen diffusion flux, two diffusion couples with different sulfur contents in the oxides were produced and investigated after heat treatment at 1473 K. The experimental results were also compared with previous work in which the oxides contained higher FeO. It was found that although the FeO content in the oxides decreased from 3wt% to 1wt% which was lower than the content corresponding to the equilibrium with molten steel at 1873 K, excess oxygen still diffused from the oxides to solid steel during heat treatment at 1473 K and formed oxide particles. In addition, increasing the sulfur content in the oxides was observed to suppress the diffusion of oxygen between the alloy and the oxides.

A new method using a confocal scanning laser microscope for melting oxide at 1673 K (1400 °C) to produce a diffusion couple, which consists of oxide and an iron-based alloy, has been developed for the investigation of a solid-state reaction between them. It is important to obtain good contact between the Fe-Mn-Si alloy and MnO-SiO2-FeO oxide before the diffusion experiment to observe diffusion of elements between them at 1473 K (1200 °C). In this system, the melting point of the oxides is higher than the temperature where the reaction would be observed. The pretreatment involving melting oxide at 1673 K (1400 °C) to obtain good contact with the alloy was carried out using a new method. The effect of the pretreatment at 1673 K (1400 °C) on the diffusion experiment at 1473 K (1200 °C) was minimized by this new method. The effect of diffusion of oxygen on the solid-state reaction between the Fe-Mn-Si alloy and MnO-SiO2-FeO oxide at 1473 K (1200 °C) was observed clearly and showed good agreement with Wagner’s model of internal oxidation of metal.

Magnesium oxide (MgO) based refractories are widely used in secondary refining processes, and their dissolution into refining slag is the primary cause of their shortened lifespan. The dissolution rate was investigated for sintered MgO and commercial MgO–C and MgO–Cr2O3 refractories in a synthesised 50CaO–45Al2O3–5SiO2 liquid (mass-%) slag. The change in slag composition was measured after a refractory sample was placed into the molten slag that was stirred by flowing argon gas at 1773 K. The dissolution rate of the sintered MgO was above those of the MgO–C and MgO–Cr2O3 refractories under the same gas flowrate, although the dissolution rate of all samples increased as the gas flowrate was increased from 25 to 75 mL·min− 1. The slag containing 5 mass-% FeO considerably promoted the dissolution of the MgO–C refractory because of the oxidation of carbon by FeO. The dissolution of all the refractories was greatly affected by penetration of the liquid slag, with the mass transfer of MgO in the penetra...

On the basis of the existing originally modified calculation models of theoretical combustion temperature (TCT), some factors, such as the combustion ratio of pulverized coal injection (PCI), the decomposition heat of PCI and the heat consumption of SiO2 in ash reduced in high temperature environment, were amended and improved to put forward a more comprehensive model for calculating TCT. The influences of each improvement on TCT were studied and the results were analyzed compared with those of traditional model and originally modified model, which showed that the present model could reflect the thermal state of a hearth more effectively.

The mathematical model of minimum safety factor that investigated the collapse trends of coke layer under different charging parameters was established firstly on the basis of the slope stabilization theory in soil mechanics, and then the model of burden profile after coke collapse was improved by adopting the predetermination of quadratic curve and energy correction methods. The research will provide theoretical evidences for describing the coke profile more accurately and technical direction for choosing suitable charging parameters of blast furnace. The results show that: it is helpful to improve the stability of coke layer with increasing chute inclining angle and length of the coke flat; when the main falling point of ore moves toward furnace wall or the coke flat is wider, the curve radian of burden profile after coke collapse becomes smaller; the ore to coke ratio distribution agrees with the gas top temperature measurement well under considering coke collapse comparing with the result of ignoring coke collapse.

The reduction degradation characteristics of typical sinter, pellet and lump ore were tested with the reducing gas conditions simulating two kinds of iron-making processes. The results show that, in the same condition of gas composition and temperature, the reduction degradation degree (RDI

The circumferential distribution characteristics of airflow in bustle pipe and each tuyere have been simulated and researched through establishing mathematical model of blast furnace (BF) hot blast systems. The disputes on the circumferential distribution characteristics of airflow in bustle pipe at home and abroad were settled. The results show that, under the premise of uniform pressure distribution in hearth and tuyere section area, except that of the nearest ones, the velocity of airflow in these tuyeres which are near to the main pipe is lower than those far away from the main pipe because of the existence of vortex. However, both the fluctuation range of all tuyeres’ air velocity and its influence on tuyere raceway depth are small and can be ignored.

The shape feature of tuyere raceway possesses an important effect on hearth state and BF operation. With analyzing channel for permeating gas and liquid in the hearth section in the position of tuyere raceway, it can be seen that the channel amount is mainly determined by section of raceway and section between the raceways. On the basic of theoretical and statistical analysis on practical production data, the new evaluation index of indicating tuyere raceway shape feature was proposed. In the condition of high blast volume, the new index AITR tended to increase and BF production was improved gradually as blast volume increases. The good evaluation character of this new index AITR has been validated with practical production data in this work.

The mathematical model of burden movement for bell-less top of BF is described in detail, and the model of burden movement on rotating chute is improved combined with collision of burden to chute and effect of coriolis force. The influence degree of charging parameters on coke main striking position and stock flow width is investigated though establishing burden model. The research shows that: The changing of coke main striking point position is obvious under increasing decline angle of chute and length of chute, and for the stock flow width, the effects of decline angle of chute and depth of stock line are most important.

To investigate the immune function of mice being given the extract of Codonopsis Radix maintained with sulfur fumigation.Mice were divided into five groups. Except the normal control group, the mice were fed with the extract of Codonopsis Radix maintained with sulfur fumigation at the high,medium and low doses, as well as medium dose of Codonopsis Radix maintained with low-temperature vacuum method, respectively. Mice were treated once a day for 10 continuous days. Weight change,organ indexes, blood cell indices, macrophage phagocytic function, and IL-2 and IFN-γ levels were measured.Compared with normal control group, Codonopsis Radix maintained with sulfur fumigation at medium and high doses inhibited body weight increase of mice; white blood cell count of high dose group was significantly increased; significant increase of macrophage phagocytosis were observed for all groups except the normal control group; and spleen index and IFN-γ level of Codonopsis Radix maintained with sulfur fumigation medium dose group were increased significantly.Codonopsis Radix maintained with sulfur fumigation can promote mouse immune function to a certain degree. There was no difference in immune effect between Codonopsis Radix maintained with sulfur fumigation and low-temperature vacuum method during experimental period. However,taking the extract of Codonopsis Radix maintained with sulfur fumigation can exert negative effect on appetite and body weight in mice.

NMR spectroscopy and X-ray crystallography, the two primary experimental methods for protein structure determination at high resolution, have different advantages and disadvantages in terms of sample preparation and data collection and analysis. It is therefore of interest to assess their complementarity when applied to small proteins. Structural genomics/proteomics projects provide an ideal opportunity to make such comparisons as they generate data in a systematic manner for large enough numbers of proteins to allow firm conclusions to be drawn. Here we report a comparison for 263 unique proteins screened by both NMR spectroscopy and X-ray crystallography in our structural proteomics pipeline. Only 21 targets (8%) were deemed amenable to both methods based on an initial 2D 15N-HSQC NMR spectrum and optimized crystallization trials. However, the use of both methods in the pipeline increased the total number of targets amenable to structure determination to 107, with 43 amenable to NMR only and 43 amenable to X-ray crystallographic methods only. We did not observe a correlation between 15N-HSQC spectral quality and the success of the same protein in crystallization screens. Similar results were found for an independent set of 159 proteins as reported in the accompanying paper by Snyder et al. Thus, we conclude that both methods are highly complementary, and in order to increase the number of proteins suited for structure determination, we suggest that both methods be used in parallel in screening of all small proteins for structure determination.

To observe different maintenance methods including vacuum-packing, storage together with tobacco, storage together with fennel, ethanol steam and sulfur fumigation for the protection of Codonopsis Radix against mildew and insect damage, and to analyze the content of polysaccharide and flavonoids of Codonopsis Radix tested in this studies, so as to look for the scientific maintenance methods replacing traditional sulfur fumigation.Except for the sulfur fumigation, naturally air-dried Codonopsis Radix was used to investigate the maintenance effectiveness of the above methods, respectively. Mildew was observed by visual inspection, and the content of polysaccharide and flavonoids were determined by ultra-violet and visible spectrophotometer. Comprehensive evaluation was given based on the results of the different maintenance methods.Low-temperature vacuum-packing, ambient-temperature vacuum-packing and sulfur fumigation could keep Codonopsis Radix from mildew and insect damage for one year, but ambient-temperature vacuum-packing showed flatulent phenomenon; ethanol steam could keep Codonopsis Radix from mildew and insects for over half a year; storage together with tobacco or fennel did not have maintenance effect. The difference of polysaccharide and flavonoids contents of all tested Codonopsis Radix was not statistically significant.Low temperature vacuum-packing maintenance can replace traditional sulfur fumigation, and it can maintain the quality of Codonopsis Radix to a certain extent.

To study the chemical constituents of Gentiana striata.The constituents were isolated from the whole herb of Gentiana striata by recrystalization, silica gel column chromatography, polyamide column chromatography and Sephadex LH-20,etc. Their structures were elucidated through MS, 1H-NMR, 13C-NMR.-8 compounds were isolated and identified as: Desoxyloganin (1), Gmephiloside (2), 5,7,4'-trihydroxy-3'-methoxyflavone (3), (+)-8-hydroxypinoresinol (4) 3S,5R, 6R, 9S-tetra-hydroxymegastigmane (5), Quercetin-3-O-beta-D-glucoside (6), Ferulic acid (7) and Ursolic acid (8).All the compounds are isolated for the first time from Gentiana striata.