Commercially available and inexpensive lithium tert -butoxide ( t BuOLi) acts as a good precatalyst for the hydroboration of esters, lactones, and epoxides using pinacolborane as a borylation agent. Functional groups such as cyano-, nitro-, amino-, vinyl, and alkynyl are unaffected under the presented hydroboration process, representing high chemoselectivity. This transformation has also been effectively applied to the synthesis of key intermediates of Erlotinib and Cinacalcet. Preliminary investigations of the mechanism show that the hydroboration proceeds through the in situ formed BH 3 species.
Contributions of different physical processes to the development of a super explosive cyclone (SEC) migrating over the Gulf Stream with the maximum deepening rate of 3.45 Bergeron were investigated using the ERA5 atmospheric reanalysis from European Centre for Medium-Range Weather Forecasts (ECMWF). The evolution of the SEC resembled the Shapiro-Keyser model. The moisture transported to the bent-back front by easterlies from Gulf Stream favored precipitation and enhanced the latent heat release. The bent-back front and warm front were dominated by the water vapor convergence in the mid-low troposphere, the cyclonic-vorticity advection in the mid-upper troposphere and the divergence in the upper troposphere. These factors favored the rapid development of the SEC, but their contributions showed significant differences during the explosive-developing stage. The diagnostic results based on the Zwack-Okossi equation suggested that the early explosive development of the SEC was mainly forced by the diabatic heating in the mid-low troposphere. From the early explosive-developing moment to maximum-deepening-rate moment, the diabatic heating, warm-air advection and cyclonic-vorticity advection were all enhanced significantly, their combination forced the most explosive development, and the diabatic heating had the biggest contribution, followed by the warm-air advection and cyclonic-vorticity advection, which is different from the previous studies of ECs over the Northwestern Atlantic. The cross section of these factors suggested that during the rapid development, the cyclonic-vorticity advection was distributed and enhanced significantly in the mid-low troposphere, the warm-air advection was strengthened significantly in the mid-low and upper troposphere, and the diabatic heating was distributed in the middle troposphere.
The climatology of different classifications (based on the intensity at the landfall time) of tropical cyclones (TCs) making landfall in Guangdong Province of China during 1951–2020 (70 years) is investigated using the best track data from the China Meteorological Administration and ERA5 reanalysis data. There were 234 TCs making landfall in Guangdong Province, with more severe tropical storms (STSs, 30.8%) and typhoons (TYs, 27.3%), and less tropical depressions (TDs, 19.7%) and tropical storms (TSs, 22.2%) during the past 70 years. The frequency of the landfall TCs had a significant interannual oscillation of 2–5 years. Landfall TCs generated over the western North Pacific (WNP) were usually more and stronger than those generated over the South China Sea (SCS). The TCs generated over the WNP had longer lifetime duration and shorter on-land duration than those generated over the SCS. TCs making landfall in western Guangdong were the most, followed by central Guangdong and eastern Guangdong. The composite analysis using TC-relative coordinates indicated that the precipitation of different classifications of TCs making landfall in Guangdong Province was asymmetric, which was stronger in the south of the TC center. The position of the maximum precipitation showed a cyclonic rotation around the TC center with increasing TC intensity. Generally, the vertical velocity, moisture flux, warm core, and vertical wind shear enhanced with the increasing landfall TC intensity. The vertical velocity and moisture flux of different classifications of TCs also showed an asymmetric structure related to the distribution of TC precipitation. TSs, STSs, and TYs had a double warm-core configuration. The precipitation of the TDs and TSs usually occurred over the down-shear of average vertical wind shear, those of the STSs and TYs over the left-of-shear.
This study aimed to address the significant bias in 0–44-day precipitation forecasts under numerical weather conditions. To achieve this, we utilized observational data obtained from 156 surface stations in the Sichuan region and reanalysis grid data from the National Centers for Environmental Prediction Climate Forecast System Model version 2. Statistical analysis of the spatiotemporal characteristics of precipitation in Sichuan was conducted, followed by a correction experiment based on the Analog Ensemble algorithm for 0–44-day precipitation forecasts for different seasons in the Sichuan region. The results show that, in terms of spatial distribution, the precipitation amounts and precipitation days in Sichuan Province gradually decreased from east to west. Temporally, the highest number of precipitation days occurred in autumn, while the maximum precipitation amount was observed in summer. The Analog Ensemble algorithm effectively reduced the error in the model forecast results for different seasons in the Sichuan region. However, the correction effectiveness varied seasonally, primarily because of the differing performance of the AnEn method in relation to precipitation events of various magnitudes. Notably, the correction effect was the poorest for heavy-rain forecasts. In addition, the degree of improvement of the Analog Ensemble algorithm varied for different initial forecast times and forecast lead times. As the forecast lead time increased, the correction effect gradually weakened.
As globalization accelerates since the late 20th century, global business, workers, and researchers are more closely connected. The scientific research in industrial-organizational psychology also reflects the progress of globalization and the changes in global workers. One of the most significant changes is the growth of usage in digital technology (e.g., the Internet and artificial intelligence), digital equipment (e.g., computers and smartphones), and digital applications (e.g., emails and social media), which shapes the way how worldwide employees work and how global businesses cooperate. Related to the development of technology, another significant change in the global business is the new forms of economy, such as knowledge economy, gig economy, digital platform-based economy, and shared economy, which changes traditional understanding of the nature of work. In addition to productivity-relevant changes, the more frequent cross-border mobility may also amplify the global uncertainty, such as the global pandemic since the outbreak of COVID-19. Globalization also comes with drastic changes in the nature of human capital and the strategic environment where fiercer competition unfolds. Therefore, firms must constantly adapt their human resource (HR) systems to ensure human capital can be developed, bundled, and leveraged in a way that can sustain strategic decisions and competitive advantage. To understand the dynamic development of HR management, literature has identified two distinctive but complementary trends: convergence and divergence. The convergence trend predicts the emergence of universal HR systems due to gradually homogenous economic systems caused by the continuous progress of industrialization and technology. By contrast, the divergence trend anticipates the coexistence of multiple distinct HR systems resulting from insurmountable barriers of institutional contexts. Empirical evidence has shown that both trends exist in various HR domains, including recruitment, selection, training, and performance management. Further, globalization also cultivates some novel HR topics with an emphasis on how to manage human capital with high cross-cultural competence. While globalization brings opportunities, organizations and employees also face new challenges in cross-cultural settings, which requires both a deeper understanding of culture and the development of relevant skills to deal with these challenges. For organizations, it is important to realize their management practices may become ineffective in another cultural setting, and thus they need to be aware of the potential impacts of culture on organizational processes. Interfirm relationships may also feature an increased level of uncertainty and instability in intercultural settings. For individual employees, interpersonal dynamics at the workplace may become more complicated because of the increasing diversity in a globalized workplace. Cultural diversity, as a double-edged sword, may bring both opportunities and challenges (e.g., when differences cause conflicts and discrimination). To resolve the culture-related challenges of globalization, both the organizations and the employees need to appreciate cultural differences and equip themselves with the resources and capabilities to make the most of diversity.
Using the TC best path data and the ERA5 reanalysis data, the statistical characteristics and environmental conditions for three types of TCs landfalling on Luzon Island and China during 1949-2020 (72 years) are investigated in this work. According to the intensity change before and after landing on Luzon Island, it can be divided into three types of TCs: “Weakening” TCs (40.0 %), and “Unchanging” TCs (33.6 %), and “Enhancing” TCs (26.4 %). The “Weakening” TCs had similar landing frequency in summer and autumn, stronger strength, longer lifespan and most of that landfalled on China with the northwest or westward track. The “Enhancing” TCs and “Unchanging” TCs occurred mostly in summer, their track were most of the westward track. The “Enhancing” TCs had the weakest strength and the shortest lifespan. It is found that the weakening effect of topography of Luzon Island to the TCs was greater than the strengthening effect. The precipitation of “Weakening” TCs was much greater than that of the other two types of TCs. And lower SST, the “Ventilation Flow” effect caused by topography of Luzon Island and abated water vapor transport were not conducive to the development of “Weakening” TCs. On the contrary, the higher SST and more weaken central VWS of “Enhancing” TCs provides favorable thermal and dynamic conditions for their development, moreover water vapor transport strengthen provided favorable moisture conditions. Affected by the convergence of topography of Luzon Island arose in three types of TCs were the greatest precipitation during landing on Luzon Island.
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