木薯园朱砂叶螨种群消长动态与空间分布型

朱砂叶螨在江西东乡木薯上的种群消长表现为2个高峰,一个出现在8月份,另一个出现在11月份,且朱砂叶螨大量爆发。运用聚集型指标、Taylor幂法则和Iwaor的m*-x直线回归分析法,得出朱砂叶螨在7~11月份的空间分布型为聚集分布。最适抽样数N=29.8+37.15/x。更多还原     

Anomalous shift in crossing frequency for the proton 1/2[541] band in175Ta

High-spin states in¹⁷⁵Ta have been populated in the¹⁶⁰Gd (¹⁹F,4n)¹⁷⁵Ta reaction with beams provided by the HI-13 tandem accelerator at the Institute of Atomic Energy in Beijing. A level scheme was constructed from γ-γ coincidence experiments. Seven decay sequences built on 5/2⁺[402], 1/2^?[541], 7/2⁺[404] and 9/2^? [514] proton Nilsson configuration have been extended to higher spin. An anomalously large delay of the neutron AB crossing built on the h_9/2 proton Nilsson State 1/2^?[541] is discussed.     

绝对稳定性的一个充要性准则及其在四阶系统中的应用

本文给出绝对稳定性的一个充要性准则.叙述了它对四阶系统的具体应用.     

Rapid hemostasis and excellent antibacterial cerium-containing mesoporous bioactive glass/chitosan composite sponge for hemostatic material

Rapid and effective hemostasis is key to controlling bleeding and reducing mortality. Here, a composite hemostatic sponge (Ce-MBG/CHT) of cerium-containing mesoporous bioactive glass (Ce-MBG) and chitosan (CHT) was prepared by a freeze-drying technique and compared with the commercially available gelatin sponge (GS), to further evaluate the hemostatic performance of composite sponge materials. The results indicate that the pore structure, porosity, and water absorption of the sponge improved following the addition of Ce-MBG. Whole blood coagulation studies suggested that Ce-MBG/CHT has superior hemostatic properties to GS and validated in vitro thrombosis, platelet adhesion and blood compatibility. In vitro coagulation studies showed that factor XII was activated by the addition of Ce-MBG, inducing the intrinsic coagulation pathway. Furthermore, we evaluated the cytocompatibility of samples after contact with L929 cells for 24, 48, and 72 h via the cytotoxicity test. Compared with GS, 4Ce-MBG/CHT was more efficient against E. coli and S. aureus. All these results indicate that Ce-MBG/CHT sponges are likely useful for rapid hemostasis.     

异龙脑甲醚断裂反应的研究

研究了异龙脑甲醚在三氯化铁 /乙酸酐存在下的断裂反应 ,并详细讨论了三氯化铁用量、反应时间和反应温度对断裂反应的影响。     

Studies on Isothermal Vapor-Liquid Equilibrium for Styrene-Cumene Binary System

This dissertation has studied the isothermal vapor-liquid equilibrium(VLE) in associating system of styrene-cumene at 353.15K and 373.15K by using a modified Rose still. The pressures are indirectly measured from the boiling points of pure waler in a separate inclined cbulliometer with a pump-like stirrer. The experimental data are well correlated with Wilson equation.     

Lifetime Measurements of the States Around the Backbend in 126Ba

The high spin states in ¹²⁶Ba were populated by means of the reaction ¹¹⁶Sn (¹⁶O,2p4n)¹²⁶Ba at the beam energy of 73MeV. Lifetimes of the states around the backbend in the yeast band were measured by using the Doppler shift attenuation method. The corresponding normalized B(E2) values are pronouncedly reduced for the 10⁺ and 12⁺ states. The experimental results are compared with the theoretical predictions of the particle-rotor model.     

Risk Transmission of Trade Price Fluctuations from a Nickel Chain Perspective: Based on Systematic Risk Entropy and Granger Causality Networks

Nickel is a strategic mineral resource, with 65% of nickel being used in stainless steel. The situation in Ukraine starting in February 2022 has led to significant fluctuations in nickel prices, with prices of nickel products along the same chain affecting and passing through each other. Using systematic risk entropy and granger causality networks, we measure the volatility risk of trade prices of nickel products using the nickel industry chain trade data from 2000–2019 and explore the transmission patterns of different volatility risk prices from the industry chain perspective. The findings show that: (1) Nickel ore has the highest risk of import trade price volatility and a strong influence, but low risk transmission. Stainless steel has the highest trade price impact but is also subject to the strongest passive influence. (2) The Americas have a higher risk of trade price volatility but a weaker influence. The influence and sensitivity of trade prices is stronger in Asia and Europe. (3) Indonesia’s stainless steel export prices have a high rate of transmission and strong influence. Germany’s ferronickel export prices are highly susceptible to external influences and can continue to spread loudly. Russian nickel ore export prices are able to quickly spread their impact to other regions.     

A microRNA-21-responsive doxorubicin-releasing sticky-flare for synergistic anticancer with silencing of microRNA and chemotherapy

A sticky-flare gold nanoparticle probe(AuNP-probe) is designed by the combination of locked nucleic acid functionalized silencing of microRNA technology for intracellular microRNA-21(miRNA-21) sensitively detecting, fluorescence imaging,localizing and silencing. The limit of detection is as low as 0.01 n M. Overexpressed miRNA-21 in cancer cells serves as endogenous drug release stimuli to trigger the release of probe-loaded doxorubicin(Dox), which soon translocates into cell nuclei. This multifunctional Dox-loaded AuNP-probe(Dox-AuNP-probe) could induce cancer cell apoptosis effectively through the synergistic effect of gene silencing and chemotherapy. This Dox-AuNP-probe exhibits superior drug potency compared to free Dox molecules, with a cell inhibition rate of 57%(but only 20% for Dox) to wild-type cancer cells and 30%(but 0% for Dox) to drug-resistent cancer cells after 72 h, and this strategy not only has the function of sensing, but also can effectively bypass drug resistance. In MCF-7 xenograft tumor-bearing mice, the Dox-AuNP-probes show greater inhibition for tumor tissues than miRNA-21 targeted AuNP-probes(Targeting-AuNP-probe) or free Dox molecules. Therefore, the Dox-AuNP-probe represents a promising nanotheranostic platform for future applications in cancer molecular imaging and therapy, especially providing a potential strategy to treat resistant cancers.     

Molecular Dynamics Insight into the CO2 Flooding Mechanism in Wedge-Shaped Pores

Because of the growing demand for energy, oil extraction under complicated geological conditions is increasing. Herein, oil displacement by CO₂ in wedge-shaped pores was investigated by molecular dynamics simulation. The results showed that, for both single and double wedge-shaped models, pore Ⅱ (pore size from 3 to 8 nm) exhibited a better CO₂ flooding ability than pore Ⅰ (pore size from 8 to 3 nm). Compared with slit-shaped pores (3 and 8 nm), the overall oil displacement efficiency followed the sequence of 8 nm > double pore Ⅱ > single pore Ⅱ > 3 nm > double pore Ⅰ > single pore Ⅰ, which confirmed that the exits of the wedge-shaped pores had determinant effects on CO₂ enhanced oil recovery over their entrances. “Oil/CO₂ inter-pore migration” and “siphoning” phenomena occurred in wedge-shaped double pores by comparing the volumes of oil/CO₂ and the center of mass. The results of the interaction and radial distribution function analyses indicate that the wide inlet and outlet had a larger CO₂–oil contact surface, better phase miscibility, higher interaction, and faster displacement. These findings clarify the CO₂ flooding mechanisms in wedge-shaped pores and provide a scientific basis for the practical applications of CO₂ flooding.