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Objective To analysis of risk factors for stress ulcers after the surgery of acute cerebral hemorrhage, and use these factors to construct a Nomogram model. Methods In this study, 300 patients with acute cerebral hemorrhage treated in The First Affiliated Hospital of University of Science and Technology of China between January 2015 and November 2020 were recruited and divided into stress ulcers group (53 patients) and non⁃ulcers group (247 patients) according to whether the postoperative period was complicated by stress ulcers. Univariate and multivariate stepwise Logistic regression were used to assess the risk factors for stress ulcers after the surgery of acute cerebral hemorrhage and the Nomogram model was established. The receiver operating characteristic (ROC) curve and calibration curve of the model were plotted, and Hosmer⁃Lemeshow goodness of fit test was performed. Results Logistic regression showed that age increased (OR=1.043, 95%CI: 1.059-1.086; P=0.042), Glasgow Coma Scale (GCS) score≤8 (OR=2.809, 95%CI: 1.018-7.740; P=0.044), the cerebral hemorrhage volume≥30 ml (OR=3.830, 95%CI: 1.342-10.933; P=0.012), neutrophil to lymphocyte ratio (NLR) increased (OR=1.090, 95%CI:1.032-1.151; P=0.002), the increase of postoperative systolic blood pressure (OR=1.031, 95%CI: 1.008-1.055; P=0.008) and postoperative intracranial infection (OR=2.809, 95%CI: 1.006-7.847; P=0.049) were the risk factors for stress ulcers after the surgery of acute cerebral hemorrhage. The Nomogram model was established based on the 6 risk factors, and the area under curve (AUC) of ROC was 0.881 (95%CI: 0.821-0.942, P=0.001); the best cut⁃off value for predicting the risk of acute postoperative cerebral hemorrhage complicated by stress ulcers was 137. The calibration curves showed good agreement between the predicted and actual probabilities, and the Hosmer⁃Lemeshow goodness of fit test showed there was no statistical difference (χ2=7.891, P=0.445), indicating that the Nomogram model has good discrimination, calibration and stability. Conclusions Over⁃age, GCS score≤8, cerebral hemorrhage volume≥30 ml, NLR increase, postoperative systolic blood pressure increase and intracranial infection were the risk factors for stress ulcers after the surgery of acute cerebral hemorrhage. In conclusion, this Nomogram model is able to individually, visually and briefly predict the risk of postoperative complications of stress ulcers in patients after the surgery of acute cerebral hemorrhage.

Green engineering is an important direction for engineering education, especially in the field of chemical engineering, where green chemical is a necessary guarantee for achieving sustainable development in the industry. How to practice the principles of green engineering in curriculum education is a problem that needs to be faced in engineering education, due to the currently educated persons are the future practitioners. The aim of this study is to integrate green techniques into an undergraduate‐level chemical design course, demonstrating how green engineering principles can be embedded in the curriculum to practice green engineering education, and thus disseminate the sustainability concept, resulting in a framework for achieving sustainable development. According to the training programme and design procedure, each student receives a product process design project and is guided by a teacher through the data review and discussion and then integrates green technologies in all aspects of the design, and the design result is evaluated. The good results of the students' design show that the undergraduate‐level chemical design course can well integrate green engineering principles and green technologies in the design, enhance the green standard of process design, broaden the students' design vision and mobilize their engineering creativity. It is a good form of green engineering education that the integration of engineering green technologies into an undergraduate‐level chemical design course, as demonstrated by the design results, which achieve effective practice of the sustainability concept and develop green education. [ABSTRACT FROM AUTHOR]

The Fe30Mn5Al alloy was oxidized at 800℃ in air for 160h, the oxidation-induced layer about 15μm thick near the scale-metal interface was induced to transform to ferrite and become enriched in Fe and depletion in Mn. The effect of the oxidation-induced Mn depletion layer on the electrochemical corrosion behavior of Fe30Mn5Al alloy was evaluated. The results show that in 1mol·L-1 Na2SO4 solution, the anodic polarization curve of the Mn depletion layer exhibits self-passivation, compared with Fe30Mn5Al austenitic alloy, and the corrosion potential Evs SCE is increased to -130mV from -750mV and the passive current density ip is decreased to 29μA/cm2 from 310μA/cm2. The electrochemical impedance spectroscopy(EIS) of the Mn depletion layer has the larger diameter of capacitive arc, the higher impedance modulus|Z|, and the wider phase degree range, and the fitted polarization resistant Rt is increased to 9.9kΩ·cm2 from 2.7kΩ·cm2 by using an equivalent electric circuit of Rs-(Rt//CPE). The high insulation of the Mn depletion layer leads to an improved corrosion resistance of Fe30Mn5Al austenitic alloy.

In this paper, a series of coordination polymers, {[Zn(adb)(L1)2]·solvent}n (L1 = solvent = N,N-dimethylacetamide, Hui-3-DMA; L1 = N,N-dimethylformamide and no solvent, Hui-3-DMF; L1 = N,N-diethylformamide and no solvent, Hui-3-DEF) have been synthesized by hydrothermal reactions of Zn(NO3)3·6H2O and 4,4′-(anthracene-9,10-diyl)dibenzoic acid (H2adb). These compounds show similar one-dimensional (1D) zig-zag chain structures, which are limited by the end-coordination of the solvent molecules. Interestingly, these compounds all show blue-emission properties, which could be easily modulated by using different solvents. Among them, Hui-3-DMA presents an excellent quantum yield performance, as high as to 54.1%, which is very promising for blue-emission materials. Moreover, various-temperature fluorescence studies reveal good linear or exponential decline trends for their emission intensity as temperature increases, demonstrating the potential of these compounds as fluorescent thermometers. [ABSTRACT FROM AUTHOR]

To improve the security of software developing and the use of trust mechanism in P2P, a mathematical model of P2P security overlay network was proposed. As the core of the model, overlay network was divided into four parts, including data confirmation layer, data capture layer, trust mechanism layer and routing layer. In the matter of functions, data confirmation layer filtered untrustworthy data; data capture layer run the vectorization of the exchanging data between logic nodes and processed relevant statistics and analysis; trust mechanism layer realized trust mechanism via identifying whether a logic node was trustworthy or not; routing layer build up mapping relationship on logic nodes and physical nodes. To enhance the security of P2P software and the convenience in the use of trust mechanism, simple vector distance classifications and kademlia algorithm were adopted on the basis of the global trust model. Simulating results show that P2P software developing can be more safe and easier under this model.

In this paper, we showed an example of acid-directed hydrothermal synthesis of three Cd-based metal–organic frameworks (MOFs) under similar conditions, namely, [Cd(TIDB)(AA)0.5(NO3)]n (1), [Cd3(TIDB)2(AA)2(H2O)2(HCOO)2]n (2), and {[Cd4(TIDB)(AA)4(H2O)5](C2H5OH)2(H2O)2}n (3) (TIDB = 1,3,5-tri(1H-imidazol-1-yl)benzene, H2AA = anthracene-9,10-dicarboxylic acid). Compound 1 was synthesized by the introduction of HNO3 as a structure-directing agent. It has 2D coordination networks with the 3,4-c bey topology. The porous 3D supramolecular framework in compound 1 is stabilized by H-bonds. Compound 2 was formed with the use of a HCOOH agent. It has a 3D coordination network with a new 3,4,5-c underlying net topology, and it is also porous. Compound 3 was obtained using a CH3COOH agent. It has a disordered non-porous 3D coordination network. Because 3 was hard to purify, 1 and 2 were chosen for further property investigation. On the one hand, fluorescence studies showed that 1 and 2 are both blue-emitting MOFs with quantum yields of 2.3% and 0.8%, respectively. On the other hand, CO2 cycloaddition performance was also tested, which revealed that 2 has a superior catalytic conversion of epoxybutane at 60 °C and 1 atm with a high yield of up to 95.6%. [ABSTRACT FROM AUTHOR]

The complex [La(NO 3)3(TBMA)2] (TBMA = N,N,N’,N’-tetrabutylmalonamide) was prepared by the extraction method and characterized by single-crystal X-ray diffraction. The complex consists of two bidentate TBMA extractant and three bidentate nitrate ions coordinated to a La3+ ion. The lanthanum(III) is 10-coordinate, being bonded to four oxygen atoms of the malonamides and six oxygen atoms of the three nitrates. The crystal data are as follows C38H76N7O13La, Mr = 977.97, triclinic system, space group P 1, a = 1.3025(12), b = 1.4353(14), c = 0.4871(13) nm, α = 70.025(17), ß = 71.411(19), γ = 84.017(18)º, V = 2.476(4) nm3, Z = 2, F(000) = 1028, D = 1.312 g.cm-3, R 1 = 0.0833, wR 2 = 0.1471.

A study has been made of the extraction of samarium(III) from nitrate solutions using N,N,N,N-tetrabutylmalonamide (TBMA) in a series of diluents. The dependence of the extraction distribution on the concentrations of aqueous nitric acid, lithium nitrate and organic TBMA was investigated. The experimental results showed that the extraction efficiency of TMBA in different diluents for Sm(III) increases in the order: chloroform, carbon tetrachloride, benzene, xylene, toluene, cyclohexane, n-hexane, n-octane. The stoichiometry of the extracted species conform to Sm(NO3)3.3TBMA in all the employed diluents. The interaction between extractant or extracted species and diluent is discussed and a quantitative expression relating the extraction constant and the parameters of the diluent has been established.