In this work, we present a systematic study of the capability of the sp3 hybridized sulfur atom for halogen bonding both in a small building block, tetrahydro-4H-thiopyran-4-one, and two larger ones ...derived from it, Schiff bases with a morpholine fragment on the other end of the molecule. These three building blocks were cocrystallized with six perhalogenated aromates: 1,4-diiodotetrafluorobenzene, 1,3,5-triiodotrifluorobenzene, 1,3-diiodotetrafluorobenzene, 1,2-diiodotetrafluorobenzene, iodopentafluorobenzene, and 1,4-dibromotetrafluorobenzene. Out of the 18 combinations, only 7 (39%) yielded cocrystals, although with a high occurrence of the targeted I···S halogen bonding motif in all cocrystals (71%), and in imine cocrystals the I···Omorpholine motif (100%) as well as, surprisingly, the I···Nimine motif (100%). The I···S halogen bonds presented in this work feature lower relative shortening values than those for other types of sulfur atoms; however, the sp3 sulfur atom could potentially be more specific an acceptor for halogen bonding.
We
report the construction of three structurally distinct self-assembled
architectures: Fe
II
12
L
12
pseudoicosahedron
1
, Fe
II
2
L
3
helicate
2
, and Fe
II
4
L
4
tetrahedron
3
, formed from a ...single triazatriangulenium subcomponent
A
under different reaction conditions. Pseudoicosahedral capsule
1
is the largest formed through subcomponent self-assembly
to date, with an outer-sphere diameter of 5.4 nm and a cavity volume
of 15 nm
3
. The outcome of self-assembly depended upon concentration,
where the formation of pseudoicosahedron
1
was favored
at higher concentrations, while helicate
2
exclusively
formed at lower concentrations. The conversion of pseudoicosahedron
1
or helicate
2
into tetrahedron
3
occurred following the addition of a CB
11
H
12
–
or B
12
F
12
2–
template.
A H(C)Rh triple resonance NMR experiment makes the rapid detection of 103Rh chemical shifts possible, which were previously beyond reach. It served to analyze a series of dirhodium and ...bismuth–rhodium paddlewheel complexes of the utmost importance for metal–carbene chemistry. The excellent match between the experimental and computed 103Rh shifts in combination with a detailed analysis of the pertinent shielding tensors forms a sound basis for a qualitative and quantitative interpretation of these otherwise (basically) inaccessible data. The observed trends clearly reflect the influence exerted by the equatorial ligands (carboxylate versus carboxamidate), the axial ligands (solvents), and the internal “metalloligand” (Rh versus Bi) on the electronic estate of the reactive Rh(II) center.
With the radical changes in information production that the Internet has introduced, we stand at an important moment of transition, says Yochai Benkler in this thought-provoking book. The phenomenon ...he describes as social production is reshaping markets, while at the same time offering new opportunities to enhance individual freedom, cultural diversity, political discourse, and justice. But these results are by no means inevitable: a systematic campaign to protect the entrenched industrial information economy of the last century threatens the promise of today's emerging networked information environment.
In this comprehensive social theory of the Internet and the networked information economy, Benkler describes how patterns of information, knowledge, and cultural production are changing-and shows that the way information and knowledge are made available can either limit or enlarge the ways people can create and express themselves. He describes the range of legal and policy choices that confront us and maintains that there is much to be gained-or lost-by the decisions we make today.
The development of very fast, clean, and selective methods for indirect labeling in PET tracer synthesis is an ongoing challenge. Here we present the development of an ultrafast photoclick method for ...the synthesis of short-lived 18F-PET tracers based on the photocycloaddition reaction of 9,10-phenanthrenequinones with electron-rich alkenes. The respective precursors are synthetically easily accessible and can be functionalized with various target groups. Using a flow photo-microreactor, the photoclick reaction can be performed in 60 s, and clinically relevant tracers for prostate cancer and bacterial infection imaging were prepared to demonstrate practicality of the method.
The Work of Communication: Relational Perspectives on Working and Organizing in Contemporary Capitalism revolves around a two-part question: "What have work and organization become under contemporary ...capitalism—and how should organization studies approach them?" Changes in the texture of capitalism, heralded by social and organizational theorists alike, increasingly focus attention on communication as both vital to the conduct of work and as imperative to organizational performance. Yet most accounts of communication in organization studies fail to understand an alternate sense of the "work of communication" in the constitution of organizations, work practices, and economies. This book responds to that lack by portraying communicative practices—as opposed to individuals, interests, technologies, structures, organizations, or institutions—as the focal units of analysis in studies of the social and organizational problems occasioned by contemporary capitalism. Rather than suggesting that there exists a canonically "correct" route communicative analyses must follow, The Work of Communication: Relational Perspectives on Working and Organizing in Contemporary Capitalism explores the value of transcending longstanding divides between symbolic and material factors in studies of working and organizing. The recognition of dramatic shifts in technological, economic, and political forces, along with deep interconnections among the myriad of factors shaping working and organizing, sows doubts about whether organization studies is up to the vital task of addressing the social problems capitalism now creates. Kuhn, Ashcraft, and Cooren argue that novel insights into those social problems are possible if we tell different stories about working and organizing. To aid authors of those stories, they develop a set of conceptual resources that they capture under the mantle of communicative relationality. These resources allow analysts to profit from burgeoning interest in notions such as sociomateriality, posthumanism, performativity, and affect. It goes on to illustrate the benefits that investigations of work and organization can realize from communicative relationality by presenting case studies that analyze (a) the becoming of an idea, from its inception to solidification, (b) the emergence of what is taken to be the "the product" in high-tech startup entrepreneurship, and (c) the branding of work (in this case, academic writing and commercial aviation) through affective economies. Taken together, the book portrays "the work of communication" as simultaneously about how work in the "new economy" revolves around communicative practice and about how communication serves as a mode of explanation with the potential to cultivate novel stories about working and organizing. Aimed at academics, researchers, and policy makers, this book’s goal is to make tangible the contributions of communication for thinking about contemporary social and organizational problems.
The four-volume set LNCS 13350, 13351, 13352, and 13353 constitutes the proceedings of the 22ndt International Conference on Computational Science, ICCS 2022, held in London, UK, in June 2022.* The ...total of 175 full papers and 78 short papers presented in this book set were carefully reviewed and selected from 474 submissions. 169 full and 36 short papers were accepted to the main track; 120 full and 42 short papers were accepted to the workshops/ thematic tracks. *The conference was held in a hybrid format This is an open access book.
Here we report the synthesis and application of trifluoromethyl thianthrenium triflate (TT-CF3 +OTf–) as a novel trifluoromethylating reagent, which is conveniently accessible in a single step from ...thianthrene and triflic anhydride. We demonstrate the use of TT-CF3 +OTf– in electrophilic, radical, and nucleophilic trifluoromethylation reactions.
The commercial fifth-generation (5G) wireless communications networks have already been deployed with the aim of providing high data rates. However, the rapid growth in the number of smart devices ...and the emergence of the Internet of Everything (IoE) applications, which require an ultra-reliable and low-latency communication, will result in a substantial burden on the 5G wireless networks. As such, the data rate that could be supplied by 5G networks will unlikely sustain the enormous ongoing data traffic explosion. This has motivated research into continuing to advance the existing wireless networks toward the future generation of cellular systems, known as sixth generation (6G). Therefore, it is essential to provide a prospective vision of the 6G and the key enabling technologies for realizing future networks. To this end, this paper presents a comprehensive review/survey of the future evolution of 6G networks. Specifically, the objective of the paper is to provide a comprehensive review/survey about the key enabling technologies for 6G networks, which include a discussion about the main operation principles of each technology, envisioned potential applications, current state-of-the-art research, and the related technical challenges. Overall, this paper provides useful information for industries and academic researchers and discusses the potentials for opening up new research directions.
High-resolution electrospray ionization ion mobility mass spectrometry has revealed a gas-phase isomer of the ubiquitous, extremely well-studied Au25(SR)18 cluster both in anionic and cationic form. ...The relative abundance of the isomeric structures can be controlled by in-source activation. The measured collision cross section of the new isomer agrees extremely well with a recent theoretical prediction ( Matus, M. F. ; et al. Chem. Commun. 2020, 56, 8087 ) corresponding to a Au25(SR)18 – isomer that is energetically close and topologically connected to the known ground-state structure via a simple rotation of the gold core without breaking any Au–S bonds. The results imply that the structural dynamics leading to isomerization of thiolate-protected gold clusters may play an important role in their gas-phase reactions and that isomerization could be controlled by external stimuli.
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