Exploring manganese pyridylporphyrin isomers for cyclohexane oxidation: First‐generation catalysts are better than third‐generation ones

Author(s):  
Alexandre Moreira Meireles ◽  
Adriano Silva Guimarães ◽  
Guilherme Rabelo Querino ◽  
Kelly Aparecida Dias de Freitas Castro ◽  
Shirley Nakagaki ◽  
...  
2021 ◽  
Author(s):  
Yifei Yu ◽  
Charles Nottage ◽  
Oscar Alvarez ◽  
Chaoqun Liu

Abstract Scientists developed many vortex identification methods and Liu classified the traditional vortex identification methods into two generations. Vorticity and vorticity-based methods belong to the first generation while eigenvalues-based methods are considered as the second generation, such as Q criterion and λci method. However, although these methods are widely used, there is still room for improvements. People used to consider direction of vorticity is the swirling axis and the magnitude of it is the rotation strength, but the predictions by vorticity does not match the experiment very well which drove scientists to develop the second-generation methods. All the second-generation methods are scalar-valued and as a result they are unable to locate the swirling. Another problem is even though second-generation methods can predict vortex better than vorticity, they are more or less contaminated by shear. To solve these problems, Liu innovated Liutex recently. Liutex is a vector quantity whose direction represents rotation axis and whose magnitude represents rotation strength. Firstly, the physical essence of rotation axis is provided coming with the mathematical definition of swirling axis which is the direction of Liutex. Secondly, orthogonal transformations are used to find out the rigid rotation speed and that speed is defined as the strength of Liutex. Wang later proposed an explicit formula to calculate Liutex strength without doing orthogonal transformations which makes it much easier to apply Liutex method. Some theories dependent on Liutex concept have been proposed these years. Liutex core lines represent the core of vortex which can uniquely and clearly show vortex structure. Principal coordinate is a special coordinate in which it is easy to decompose the velocity gradient tensor into rotation, shear and stretching parts correctly. And principal decomposition is the decomposition in principal coordinate. The Liutex theory system is gradually formed and they are considered as the third generation by Liu.


2020 ◽  
Vol 15 (4) ◽  
pp. 648-674 ◽  
Author(s):  
David Figlio ◽  
Umut Özek

We use matched birth records and longitudinal student records in Florida to investigate whether first-, second-, and third-generation Asian and Hispanic immigrants have different educational success (measured by test scores, disciplinary problems, truancy, high school graduation, and college readiness). We find that, for both Asian and Hispanic students, early-arriving first generation immigrants perform better than do second-generation immigrants, who perform better than third-generation immigrants. The earlier the arrival, the better the students tend to perform. There is therefore a general pattern of successively reduced achievement in the generations following the generation that immigrated to the United States.


2012 ◽  
Vol 5 (1) ◽  
pp. 97-110 ◽  
Author(s):  
Yael Darr

Since the 1990s, a new type of Holocaust story has been emerging in Israeli children's literature. This new narrative is directed towards very young children, from preschool to the first years of elementary school, and its official goal is to instil in them an authentic ‘first Holocaust memory’. This essay presents the literary characteristics of this new Holocaust narrative for children and its master narrative. It brings into light a new profile of both writers and readers. The writers were young children during the Holocaust, and first chose to tell their stories from the safe distance of three generations. The readers are their grand-children and their grand-children's peers, who are assigned an essential role as listeners. These generational roles – the roles of a First Generation of writers and of a Third Generation of readers – are intrinsically familial ones. As such, they mark a significant change in the profile of yet another important figure in the Israeli intergenerational Holocaust discourse, the agent of the Holocaust story for children. Due to the new literary initiatives, the task of providing young children with a ‘first Holocaust memory’ is transferred from the educational authority, where it used to reside, to the domestic sphere.


1965 ◽  
Vol 97 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
H. J. Herbert

AbstractIn Nova Scotia one leaf cluster with an adjoining 1 inch of twig taken from the inside of each of 10 apple trees replicated four times is an adequate sample unit to measure the density of the brown mite.The brown mite has one generation with a partial second in some orchards and one with a partial second and partial third in others. The first generation adults in the bivoltine and trivoltine populations lay summer eggs on the leaves and twigs, and diapause eggs on tin twigs. The second generation adults in the bivoltine populations lay only diapause eggs; in the trivoltine populations they lay both summer and diapause eggs. The adults of the third generation lay only diapause eggs.The brown mite is found on both the leaves and woody parts of the tree. In orchards with bivoltine populations the proportion of mites on leaves reached a peak of 80% by mid-July, but thereafter gradually decreased to 10% by the end of August. However, in orchards with trivoltine populations the proportion of mites on leaves reached a peak of 80 to 90% by mid-July, remained constant until mid-August, and thereafter decreased to approximately 40% by the end of August.The number of diapause eggs laid by adults of each generation in both the bivoltine and trivoltine populations varies widely. The eggs are deposited on the trunk as well as on the branches, with the heaviest deposition in the central area of the tree. The diapause eggs laid by adults of the first generation are the last to hatch and those laid by the third generation are the first to hatch the following spring.The factors responsible for the differences in the number of generations and in the number of diapause eggs laid are unknown.


2014 ◽  
Vol 42 (1) ◽  
pp. 121-134
Author(s):  
Alexandre Peñalver i Cabré

Human Right to Environment is one the most relevant Third Generation Human Rights which includes new universal needs arisen from the last third of 20th century. These new human rights add as an additional layer to the First Generation Human Rights (civil and political rights from the end of 18th century) and to the Second Generation Human Rights (economic, social and cultural rights from 19th century).


2012 ◽  
Vol 23 (2) ◽  
pp. 65-76
Author(s):  
Willi Goetschel

This paper examines Rosenzweig?s philosophic project in the context of his time as a critical intervention in the discussion of the place of Jewish thought in the university and in society. If Hermann Cohen represented the first generation of Jewish philosophers claiming that participation in the university is constitutive for the institution?s claim to universalism, the second generation-represented by Martin Buber - was more diffident about the university and its openness. For Buber, literary modernism offered what the university would refuse. Disappointed about the failure of the recognition of the efforts of the previous two generations, Rosenzweig represents the third generation. He turns the situation into a creative response anchoring philosophy as a project that calls for a resolute move outside the university.


Author(s):  
Matthew D. Krasowski ◽  
Thomas A. Long ◽  
Christine L. H. Snozek ◽  
Annabel Dizon ◽  
Barbarajean Magnani ◽  
...  

Context.— Therapeutic drug monitoring has traditionally been widely used for first-generation antiepileptic drugs (AEDs) such as carbamazepine and phenytoin. The last 2 decades have seen the introduction of second- and third-generation AEDs (eg, lamotrigine, levetiracetam, and topiramate) into clinical practice. Objective.— To use data from the College of American Pathologists Therapeutic Drug Monitoring, Extended proficiency testing survey to determine the performance of assays used for therapeutic drug monitoring of newer AEDs, including comparison of enzyme immunoassay and chromatographic techniques. Design.— Six years of proficiency testing surveys were reviewed (2013–2018). Results.— Steady growth was seen in participant volumes for newer AEDs. The analytical performance of automated enzyme immunoassays for lamotrigine, levetiracetam, and topiramate was similar to that of chromatographic methods, consistent with published literature using patient samples for comparisons. The majority of participating laboratories now use enzyme immunoassays to measure levetiracetam. Conclusions.— Survey results reflect steadily growing interest in therapeutic drug monitoring of newer AEDs. The increasing availability of robust immunoassays for new AEDs should facilitate their clinical utility, especially for clinical laboratories that do not perform chromatographic assays for therapeutic drug monitoring.


2019 ◽  
pp. 47-64
Author(s):  
Karl Raitz

Early-nineteenth-century farmers and millers were often craft distillers, mashing and fermenting grain meal in wooden barrels before distilling the liquid in small copper pot stills. Waterwheels powered the first-generation creek-side mills and distilleries. Wood fueled early steam engines; the use of coal required access to better transportation. Second-generation distilleries, operating from the 1830s to the 1880s, used traditional pot stills,although some adopted new column stills, perfected in Scotland, when they began to mechanize. Old still buildings were often modified to accommodate new machinery. Distillers stored whiskey-filled wooden barrels in stack warehouses to age. Industrialization required a larger labor force. By 1880, businesses in Louisville and other river cities were producing steam engines, boilers, and related equipment. Third-generation distilleries operated from the 1880s to 1920; their high-capacity output required more grain and fuel, mandating locations near railroad tracks or navigable rivers. Complementary industries such as cooperages, metal fabricators, slaughterhouses, and tanneries were attracted to urban, rail-side distilleries.


2020 ◽  
Vol 198 ◽  
pp. 04011
Author(s):  
Yuqian Zhang

With the rapid development of technologies, the third generation semiconductor is being studied, as it is leading to the significant change in industry like the manufacture of PC, mobile devices, lighting etc. Till now, due to its irreplaceable physical characteristics, third generation semiconductor is applied to lots of fields. This paper analyzes the application of third generation semiconductor, namely, GaN and SiC. Their characteristics including advantages as well as disadvantages will be discussed through reviewing the result of relevant researches. Meanwhile, comparison between the third generation semiconductors and the second as well as the first generation semiconductors is made in this paper. Through the comparison of physical characteristics, recent marketing, production and limitations, the advantages and disadvantages of each semiconductor is analyzed and the suggestion of how to avoid the disadvantage through application is proposed. At last, the future development is predicted. According to the analysis result of this paper, silicon poses more merits. Silicon is not only cheaper but also performs better making it a preference of GaAs, and GaN in the domain of IC. The second generation semiconductor, GaAs, is widely used in the circuits and photoelectric integration. Furthermore, the third semiconductor material GaN is a promising material for power switching and communication and has the great possibility to play a crucial role in market.


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