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1.
Chem Sci ; 13(40): 11710-11720, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36348954

RESUMO

Recent assessments alarmingly indicate that many of the world's leading chemicals are transgressing one or more of the nine planetary boundaries, which define safe operating spaces within which humanity can continue to develop and thrive for generations to come. The unfolding crisis cannot be ignored and there is a once-in-a-century opportunity for chemistry - the science of transformation of matter - to make a critical difference to the future of people and planet. How can chemists contribute to meeting these challenges and restore stability and strengthen resilience to the planetary system that humanity needs for its survival? To respond to the wake-up call, three crucial steps are outlined: (1) urgently working to understand the nature of the looming threats, from a chemistry perspective; (2) harnessing the ingenuity and innovation that are central to the practice of chemistry to develop sustainable solutions; and (3) transforming chemistry itself, in education, research and industry, to re-position it as 'chemistry for sustainability' and lead the stewardship of the world's chemical resources. This will require conservation of material stocks in forms that remain available for use, through attention to circularity, as well as strengthening engagement in systems-based approaches to designing chemistry research and processes informed by convergent working with many other disciplines.

2.
Inorg Chem ; 61(40): 15841-15852, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36166338

RESUMO

Molecular catalysis for selective CO2 electroreduction into CO can be achieved with a variety of metal complexes. Their immobilization on cathodes is required for their practical implementation in electrolytic cells and can benefit from the advantages of a solid material such as easy separation of products and catalysts, efficient electron transfer to the catalyst, and high stability. However, this approach remains insufficiently explored up to now. Here, using an appropriate and original modification of the cyclam ligand, we report a novel [Ni(cyclam)]2+ complex which can be immobilized on carbon nanotubes. This material, once deposited on a gas diffusion layer, provides a novel electrode which is remarkably selective for CO2 electroreduction to CO, not only in organic solvents but also, more remarkably, in water, with faradic efficiencies for CO larger than 90% and current densities of 5-10 mA cm-2 during controlled potential electrolysis in H-cells.

3.
R Soc Open Sci ; 9(4): 212004, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35601450

RESUMO

Strengthening resilience-elasticity or adaptive capacity-is essential in responding to the wide range of natural hazards and anthropogenic changes humanity faces. Chemistry's roles in resilience are explored for the first time, with its technical capacities set in the wider contexts of cross-disciplinary working and the intersecting worlds of science, society and policy. The roles are framed by chemistry's contributions to the sustainability of people and planet, examined via the human security framework's four material aspects of food, health, economic and environmental security. As the science of transformation of matter, chemistry is deeply involved in these material aspects and in their interfacing with human security's three societal and governance aspects of personal, community and political security. Ultimately, strengthening resilience requires making choices about the present use of resources as a hedge against future hazards and adverse events, with these choices being co-determined by technical capacities and social and political will. It is argued that, to intensify its contributions to resilience, chemistry needs to take action along at least three major lines: (i) taking an integrative approach to the field of 'chemistry and resilience'; (ii) rethinking how the chemical industry operates; and (iii) engaging more with society and policy-makers.

4.
Angew Chem Int Ed Engl ; 60(49): 25610-25623, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34704655

RESUMO

Human security, defined as "freedom from want and fear and freedom to live in dignity", provides an overarching concept to address threats to human security dimensions such as health, food, economics, the environment and sustainable development, while placing the individual at the centre of attention. Chemistry is central to addressing these challenges, but surprisingly its role and contributions to human security have hitherto not been explicitly set out. This article situates chemistry in the human security framework, highlighting areas where chemistry knowledge, methods and products are vital. It underscores three complementary facets: 1) chemistry contributes to many dimensions of human security, but needs to do much more in the light of oncoming global challenges; 2) the human security framing illuminates areas where chemistry itself needs to adapt to contribute better, by intensification of current approaches and/or by building or strengthening chemistry tools, skills and competencies; and 3) repositioning as central to human security affords chemistry a powerful opportunity to refresh itself as a science for the benefit of society-and it will need to engage more directly and dynamically at the interface of science, society and policy in order to do so.


Assuntos
Políticas , Ciência , Previdência Social , Humanos
5.
R Soc Open Sci ; 7(5): 200554, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32537231

RESUMO

Against a backdrop of rapidly changing social, economic and geopolitical settings and ideologies, the world is facing a wide range of challenges, including in biodiversity, climate, energy, the environment, food, health and water. These can only be addressed by fully harnessing key capacities that science offers. However, there is a crisis of trust in science which affects some sections of society and some policy-makers, impairing the capacity of science to deliver its essential roles. This damaged relationship between science, society and policy has immense health, economic and social consequences and implications for sustainability of the entire planet. Scientists must strive collectively to re-establish trust by society and politicians where it is damaged, and reinforce conviction of science's central importance in underpinning policy. Science's roles must in turn be acknowledged by policies that sustain innovation and freedom to work without political interference or constraints. A well-functioning and trusting relationship between science, society and policy-makers offers a potent means to thwart and mitigate emergent global challenges.

6.
Angew Chem Int Ed Engl ; 59(6): 2150-2154, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31589804

RESUMO

In chemistry and other sciences, hype has become commonplace, compounded by the hypocrisy of those who tolerate or encourage it while disapproving of the consequences. This reduces the credibility and trust upon which all science depends for support. Hype and hypocrisy are but first steps down a slippery slope towards falsification of results and dissemination of fake science. Systemic drivers in the contemporary structure of the science establishment encourage exaggeration and may lure the individual into further steps along the hype-hypocrisy-falsification-fakery continuum. Collective, concerted intervention is required to effectively discourage entry to this dangerous pathway and to restore and protect the probity and reputation of the science system. Chemists must play and active role in this effort.

7.
R Soc Open Sci ; 6(5): 190161, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31218057

RESUMO

Computers, the Internet and social media enable every individual to be a publisher, communicating true or false information instantly and globally. In the 'post-truth' era, deception is commonplace at all levels of contemporary life. Fakery affects science and social information and the two have become highly interactive globally, undermining trust in science and the capacity of individuals and society to make evidence-informed choices, including on life-or-death issues. Ironically, drivers of fake science are embedded in the current science publishing system intended to disseminate evidenced knowledge, in which the intersection of science advancement and reputational and financial rewards for scientists and publishers incentivize gaming and, in the extreme, creation and promotion of falsified results. In the battle for truth, individual scientists, professional associations, academic institutions and funding bodies must act to put their own house in order by promoting ethics and integrity and de-incentivizing the production and publishing of false data and results. They must speak out against false information and fake science in circulation and forcefully contradict public figures who promote it. They must contribute to research that helps understand and counter false information, to education that builds knowledge and skills in assessing information and to strengthening science literacy in society.

8.
Angew Chem Int Ed Engl ; 58(10): 2912-2913, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30701633

RESUMO

"The entire field of science needs to enhance its performance with regard to equality, diversity, and inclusion …" Read more in the Editorial by S. A. Matlin, V. W. W. Yam et al.

9.
Chem Rec ; 19(2-3): 675-686, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30521082

RESUMO

Beyond individual scientific virtuosity and creativity that leading figures in chemistry have displayed, they have sometimes conveyed wider messages of significance beyond their own professional specialization. They include insights into broader aspects of science, society or the ways of the world. On the other hand, the words, attitudes and actions of eminent chemists from former times have not always presented good models for others to follow, whether judged by their own contemporary or our present standards. Both positive and negative lessons may convey to us something about humanity in general or the nature of our current predicaments and challenges. In an era when science is more necessary than ever to help meet oncoming global challenges, yet the principles and results of science are irrationally questioned, it is particularly relevant to re-connect with the broad insights and messages that can be derived from examining the thoughts and deeds of chemistry icons from the past.

10.
Angew Chem Int Ed Engl ; 57(45): 14690-14698, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30079534

RESUMO

There has been mounting concern over the absence of gender equality in the sciences in recent years. This has been accompanied by a broadening of the perspective, in order to address issues of equality, diversity and inclusion, relating to a wide range of circumstances in which individuals suffer discrimination. While some progress has been made in some countries, nationally or at the level of institutions, much more needs to be done. The chemical sciences can play a leading role in addressing biases, through 1) becoming a model of good systemic practice in policies, processes, and actions; 2) developing practical skills through training in cultural competence; and 3) promoting a stronger evidence base to uncover both the extent of problems and the degree to which approaches to improve equality, diversity, and inclusion are working.


Assuntos
Química , Competência Cultural , Pesquisa , Discriminação Social , Química/educação , Química/legislação & jurisprudência , Química/organização & administração , Competência Cultural/legislação & jurisprudência , Competência Cultural/organização & administração , Diversidade Cultural , Feminino , Humanos , Masculino , Pesquisa/educação , Pesquisa/legislação & jurisprudência , Pesquisa/organização & administração , Sexismo/legislação & jurisprudência , Sexismo/prevenção & controle , Discriminação Social/legislação & jurisprudência , Discriminação Social/prevenção & controle
11.
ACS Omega ; 2(10): 6819-6821, 2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30023534

RESUMO

The indispensable contributions to health made by the chemical sciences have become increasingly constrained by three systemic factors. These involve fragmentations: in the way that the chemicals sciences are structured, practiced, and inter-related to aspects of health; in the combination of public and private efforts delivering medicinal products; and in the regulatory systems which oversee health-related issues across health, food, and the environment. Interlinked systemic reforms are advocated, involving (1) recontextualization of the chemistry/health interface through creating a recognized field of "the chemical sciences and health"; (2) determined and comprehensive efforts, by countries wishing to retain or strengthen their pharmaceutical development capacities, to reinforce their education, research, and innovation eco-systems; and (3) adoption of an integrated approach to the regulation of pharmaceuticals, food, and the environment.

14.
15.
J Sep Sci ; 38(14): 2545-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25931280

RESUMO

The absolute configuration of rhizopine, an opine-like natural product present in nitrogen-fixing nodules of alfalfa infected by rhizobia, is elucidated using a combination of state-of-the-art analytical and semi-preparative supercritical fluid chromatography and vibrational circular dichroism spectroscopy. A synthetic peracetylated racemate was fractionated into its enantiomers and subjected to absolute configuration analysis revealing that natural rhizopine exists as a single enantiomer. The stereochemistry of non-derivatized natural rhizopine corresponds to (1R,2S,3R,4R,5S,6R)-4-amino-6-methoxycyclohexane-1,2,3,5-tetraol.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Dicroísmo Circular/métodos , Inositol/análogos & derivados , Inositol/química , Medicago sativa/microbiologia , Conformação Molecular , Estrutura Molecular , Rhizobium , Solventes , Espectrofotometria Infravermelho , Estereoisomerismo , Vibração
16.
J Mol Graph Model ; 43: 1-10, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23666030

RESUMO

A conceptual basis to define and detect organic functional groups is developed. The basic model of a functional group is termed as a primary functional group and is characterized by a group center composed of one or more group center atoms bonded to terminal atoms and skeletal carbon atoms. The generic group center patterns are identified from the structures of known functional groups. Accordingly, a chemical ontology 'Font' is developed to organize the existing functional groups as well as the new ones to be defined by the chemists. The basic model is extended to accommodate various combinations of primary functional groups as functional group assemblies. A concept of skeletal group is proposed to define the characteristic groups composed of only carbon atoms to be regarded as equivalent to functional groups. The combination of primary functional groups with skeletal groups is categorized as skeletal group assembly. In order to make the model suitable for reaction modeling purpose, a Graphical User Interface (GUI) is developed to define the functional groups and to encode in XML format appropriate to detect them in chemical structures. The system is capable of detecting multiple instances of primary functional groups as well as the overlapping poly-functional groups as the respective assemblies.


Assuntos
Carbono/química , Modelos Químicos , Interface Usuário-Computador , Modelos Estruturais , Linguagens de Programação , Software
17.
J Colloid Interface Sci ; 394: 252-62, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23261338

RESUMO

Mesoporous TiO(2) with a hierarchically 3D dendrimeric nanostructure comprised of nanoribbon building units has been synthesized via a spontaneous self-formation process from various titanium alkoxides. These hierarchically 3D dendrimeric architectures can be obtained by a very facile, template-free method, by simply dropping a titanium butoxide precursor into methanol solution. The novel configuration of the mesoporous TiO(2) nanostructure in nanoribbon building units yields a high surface area. The calcined samples show significantly enhanced photocatalytic activity and degradation rates owing to the mesoporosity and their improved crystallinity after calcination. Furthermore, the 3D dendrimeric architectures can be preserved after phase transformation from amorphous TiO(2) to anatase or rutile, which occurs during calcination. In addition, the spontaneous self-formation process of mesoporous TiO(2) with hierarchically 3D dendrimeric architectures from the hydrolysis and condensation reaction of titanium butoxide in methanol has been followed by in situ optical microscopy (OM), revealing the secret on the formation of hierarchically 3D dendrimeric nanostructures. Moreover, mesoporous TiO(2) nanostructures with similar hierarchically 3D dendrimeric architectures can also be obtained using other titanium alkoxides. The porosities and nanostructures of the resultant products were characterized by SEM, TEM, XRD, and N(2) adsorption-desorption measurements. The present work provides a facile and reproducible method for the synthesis of novel mesoporous TiO(2) nanoarchitectures, which in turn could herald the fabrication of more efficient photocatalysts.

18.
J Colloid Interface Sci ; 368(1): 128-38, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22047917

RESUMO

Various hierarchical porous titania with high surface area over 600 m(2)/g have been synthesized via a spontaneous self-formation process from titanium alkoxides by a water adjusting approach using acetonitrile as reaction medium. The reactivity of metal alkoxides and the water content in acetonitrile medium on the resultant structure have been investigated. The porosities of the products were characterized by SEM, TEM and N(2) adsorption-desorption measurements. The observation on the evolution of porous structure with increasing water content in reaction system is essential for a better understanding of hierarchical porous structure formation over different length scales by this self-formation process. The creation of macro/micropores in photocatalytic titania materials has been found to enhance the photocatalytic activity due to both the action of macrochannels as light harvester and the easy diffusion effect of organic molecules. The present work shows clearly that hierarchically porous titania with the presence of macroporous structure and high surface area can be very efficient photocatalysts, suggesting their potential applications in water treatment as decontamination materials.

20.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): o948, 2010 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-21580752

RESUMO

The relative configuration of the endo isomer of the title compound, C(9)H(14)O(4)S, has been established and the conformation of the diastereoisomer is discussed. The five-membered ring adopts an envelope conformation. The conformation of the methane-sulfonate substituent is stabilized by inter-molecular C-H⋯O hydrogen bonds. The crystal packing results in alternating layers of polar methane-sulfonates and stacked bicyclo-hexa-nyl rings parallel to ab.

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