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AbstractTo optimize the drying process of bamboo bundles, this study investigates the heat and mass transfer behavior during the drying process by using temperature sensors to measure the temperature field at different positions and track the overall moisture content over time. Additionally, a heat transfer model is used to simulate and predict the drying process. The analysis of the experimental results indicates that the diameter of the bamboo bundles has a greater impact on the drying rate than the drying temperature. At the same temperature, the drying time significantly decreases as the temperature increases. Under drying conditions at 80 °C, the average drying rate constant is 0.072 for bamboo bundles with a diameter of 40 mm, whereas it is only 0.015 for bundles with a diameter of 100 mm. Using Newton’s law of cooling, the convective heat transfer coefficient calculation method was derived. The average convective heat transfer coefficients at 40, 60, and 80 °C were calculated to be 6.16 W/(m2 K), 7.14 W/(m2 K), and 7.22 W/(m2 K), respectively. A mathematical model was established for the temperature at the center of the bamboo bundles, the temperature of the drying medium, the diameter of the bamboo bundles, and the drying time. This model effectively simulates the temperature variation inside the bamboo bundles, and the temperature simulation data fits well with the measured values, with a standard error of less than 2.8 °C and a prediction error of less than 6.1%. This coupled model and method provide a theoretical basis for predicting and controlling the bamboo bundle drying process, reducing energy and time consumption in actual production. [ABSTRACT FROM AUTHOR]

α‐Olefins are valued and abundant building blocks from fossil resources. They are widely used to provide small‐molecule or polymeric products. Despite numerous advantages of radical polymerization, it has been well‐documented as textbook knowledge that α‐olefins and their functionalized derivatives cannot be radically homopolymerized because of the degradative chain transfer side reactions. Herein, we report our studies on the homopolymerization of thiocyanate functionalized α‐olefins enabled by 1,4‐cyano group migration under radical conditions. By this approach, a library of ABC sequence‐controlled polymers with high molecular weights can be prepared. We can also extend this strategy to the homopolymerization of α‐substituted styrenic and acylate monomers which are known to be challenging to achieve. Overall, the demonstrated functional group migration radical polymerization could provide new possibilities to synthesize polymers with unprecedented main chain sequences and structures. These polymers are promising candidates for novel polymeric materials. [ABSTRACT FROM AUTHOR]

Objective To explore the implementation and continued use of high-efficiency contraception in over-40-year-old women immediately after induced abortion, and evaluate the value of post-abortion care (PAC) Performance Standards in reducing the rate of unintended pregnancy in senior women. Methods Clinical data of 126 women over 40 years of age who underwent abortion in our hospital in the year of 2019, and of 252 woman at childbearing age (20~40 years old) undergoing abortion during the same period were collected in this study. All cases were given services in accordance with the PAC Performance Standards, and then followed up for 1, 3, and 6 months. The daily contraceptive methods, cause of this unexpected pregnancy, implementation of immediate and efficient contraception after abortion, rate of continued use of high-efficiency contraceptive methods (long- or short-acting contraceptive methods), and incidence of another unexpected pregnancy were analyzed and compared between the 2 groups. Results Before this accidental abortion, the time of abortions was significantly higher in the elderly group than the childbearing age group (t=6.986, P < 0.001). Although the 2 groups differed in the composition ratio of the 2 contraceptive methods (Chi-square=30.612, P < 0.001), condoms were still the most commonly used method (50.79% vs 72.22%). The implementation rate of immediate and efficient contraception after abortion was obviously higher in the elderly group than the childbearing age group (96.83% vs 90.87%, Chi-square=4.487, P=0.034), but no statistical difference was seen (Chi-square=2.550, P=0.110). The elderly group had higher follow-up rate at 1, 3, and 6 months postoperatively (P < 0.05), higher implementation rate of effective contraceptive measures (P < 0.05) at the time points of follow-up, and lower incidence of unintended pregnancy at 6 months postoperatively (Chi-square=4.845, P=0.028) when compared with the childbearing age group. Conclusion The women over 40 years of age have higher rates of implementation and continued use of high-efficiency contraception after accidental pregnancy, and lower re-unexpected pregnancy than the women of childbearing age. PAC Performance Standards are helpful to the senior women receiving effective and long-acting contraceptive measures immediately after abortion, increasing their continued rate, reducing the rates unintended pregnancy and repeated abortion.