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"Qiu, Jian"
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دراسات حول الفضاء العالمي و\الحزام والطريق\ : (مجلد الثقافة)
ينطلق هذا المجلد من العلاقة الهيكلية بين \"الفضاء\" و\"الثقافة\"، ويجمع بين مفهوم \"الفضاء\" في الجغرافيا ومفهوم \"السياق\" في الدراسات الثقافية وغيرهم من المفاهيم الأخرى، ويشرح نماذج ودلالات وأهداف مبادرة \"الحزام والطريق\" في سياق الحضارة الحديثة، ويصف صورة امتداد الحضارة على المحور التاريخي لـ \"الحزام والطريق\"، ويحلل الدلالة الثقافية في كل من اتجاه القيمة وبناء القوة الناعمة وإنشاء السياق الشرقي الخاصين بمبادرة \"الحزام والطريق\"، ويفسر علاقة الارتباط بين الثقافة الوطنية لـ \"الحزام والطريق\" والفضاء الوطني، ويكشف عن السرد عبر الفضاء للرموز الثقافية لـ \"الحزام والطريق\" ويوضح التعبير الرقمي والمرئي لواقع \"الحزام والطريق\"
Book
A general design approach toward covalent organic frameworks for highly efficient electrochemiluminescence
Electrochemiluminescence (ECL) plays a key role in analysis and sensing because of its high sensitivity and low background. Its wide applications are however limited by a lack of highly tunable ECL luminophores. Here we develop a scalable method to design ECL emitters of covalent organic frameworks (COFs) in aqueous medium by simultaneously restricting the donor and acceptor to the COFs’ tight electron configurations and constructing high-speed charge transport networks through olefin linkages. This design allows efficient intramolecular charge transfer for strong ECL, and no exogenous poisonous co-reactants are needed. Olefin-linked donor-acceptor conjugated COFs, systematically synthesized by combining non-ECL active monomers with C
2v
or C
3v
symmetry, exhibit strong ECL signals, which can be boosted by increasing the chain length and conjugation of monomers. The present concept demonstrates that the highly efficient COF-based ECL luminophores can be precisely designed, providing a promising direction toward COF-based ECL phosphors.
Electrochemiluminescence (ECL) plays a key role in analysis and sensing but its application is limited by a lack of highly tunable luminophores. Here, the authors demonstrate the design of high efficient ECL luminophores of covalent organic frameworks (COFs) in aqueous media by simultaneously restricting the donor and acceptor to the COFs’ electron configurations and constructing charge transport networks through olefin linkages.
Journal Article
دراسات حول الفضاء العالمي و\الحزام والطريق\ : (مجلد السياحة)
إن استراتيجية \"الحزام والطريق\" هي عملية طويلة الأمد، ولا يمكن وصف دورها في تعزيز تنمية السياحة ببساطة. يحلل \"الفضاء العالمي و\"حزام واحد وطريق واحد\" حجم السياحة\" الوضع الحالي لتنمية السياحة العالمية في سياق استراتيجية \"حزام واحد وطريق واحد\"، ويقدم بالتفصيل تطور السياحة العالمية والخلفية السياحية. \"حزام وطريق\"، بما في ذلك نظرة عامة على صناعة السياحة العالمية، والاتجاهات الجديدة في تنمية السياحة العالمية ونمط السياحة العالمية، وما إلى ذلك، واستنادا إلى تحليل فرص وتحديات تنمية السياحة العالمية والصينية، والتأثير الترويجي لـ \"حزام واحد وطريق واحد\"، وتم تفسير استراتيجية \"الحزام والطريق\" لتنمية السياحة.
Book
Exclusive production of a pair of high transverse momentum photons in pion-nucleon collisions for extracting generalized parton distributions
A
bstract
We show that exclusive production of a pair of high transverse momentum photons in pion-nucleon collisions can be systematically studied in QCD factorization approach if the photon’s transverse momentum
q
T
with respect to the colliding pion is much greater than Λ
QCD
. We demonstrate that the leading power non-perturbative contributions to the scattering amplitudes of this exclusive process are process-independent and can be systematically factorized into universal pion’s distribution amplitudes (DAs) and nucleon’s generalized parton distributions (GPDs), which are convoluted with corresponding infrared safe and perturbatively calculable short-distance hard parts. The correction to this factorized expression is suppressed by powers of 1/
q
T
. We demonstrate quantitatively that this new type of exclusive processes is not only complementary to existing processes for extracting GPDs, but also capable of providing an enhanced sensitivity to the dependence of both DAs and GPDs on the active parton’s momentum fraction
x
. We also introduce additional, but the same type of exclusive observables to enhance our capability to explore GPDs, in particular, their
x
-dependence.
Journal Article
دراسات حول الفضاء العالمي و\الحزام والطريق\ : (مجلد البيئة الإيكولوجية)
إن معظم الدول والمناطق على طول «الحزام والطريق» هي دول نامية، وتعاني جميعا من مشكلات في البيئة الإيكولوجية أكثر أو أقل، كما إنها تواجه تحديات ضخمة في التوازن بين التنمية وحماية البيئة. وتواجه هذه البلدان النامية فرصا غير مسبوقة أتاحها المفهوم الاستراتيجي لمبادرة «الحزام والطريق»، كما أن كيفية التعامل مع التحدي المتمثل في حماية البيئة الإيكولوجية أثناء بناء وتطوير «الحزام والطريق» هي المهمة الأساسية التي تواجهها البلدان النامية بما فيها الصين. ويناقش هذا الكتاب ويلخص الخلفية البيئية الإيكولوجية للبلدان/ المناطق المشاركة في مبادرة \"الحزام والطريق\" والمشكلات الرئيسية في هذا الجانب.
Book
Rozansky–Witten Theory, Localised Then Tilted
The paper has two parts, in the first part, we apply the localisation technique to the Rozansky–Witten theory on compact hyperkähler targets. We do so via first reformulating the theory as some supersymmetric sigma-model. We obtain the exact formula for the partition function with Wilson loops on
S
1
×
Σ
g
and the lens spaces, the results match with earlier computations using Feynman diagrams on K3. The second part is motivated by a very curious paper (Gukov in J Geom Phys 168, 104311, 2021), where the equivariant index formula for the dimension of the Hilbert space of the Rozansky–Witten theory is interpreted as a kind of Verlinde formula. In this interpretation, the fixed points of the target hyperkähler geometry correspond to certain ‘states’. We extend the formalism of part one to incorporate equivariance on the target geometry. For certain non-compact hyperkähler geometry, we can apply the tilting theory to the derived category of coherent sheaves, whose objects label the Wilson loops, allowing us to pick a basis for the latter. We can then compute the fusion products in this basis and we show that the objects that have diagonal fusion rules are intimately related to the fixed points of the geometry. Using these objects as basis to compute the dimension of the Hilbert space leads back to the Verlinde formula, thus answering the question that motivated the paper.
Journal Article
دراسات حول الفضاء العالمي و\الحزام والطريق\ : (مجلد الموانئ البحرية)
ينقسم الكتاب إلى خمسة فصول، يقدم الفصل الأول نظام الموانئ العالمي والعلاقات بين المدن الساحلية والتعاون في مجال الموانئ، ويناقش الفصل الثاني الخدمات اللوجستية البحرية العالمية وتطوير لوجستيات الموانئ الرئيسية، ويتناول الفصل الثالث نظام الموانئ في الصين وخصائصه. الاستجابة العالمية: يحلل الفصل الرابع بشكل رئيسي مؤشر البلطيق، وهو مؤشر تقييم مراكز الشحن الدولية، ويناقش الفصل الخامس نمط الموانئ العالمية وتغيرات النظام وتطور النقل البحري بناءً على منظور عالمي.
BOOK
Synthesis of propenone-linked covalent organic frameworks via Claisen-Schmidt reaction for photocatalytic removal of uranium
The type of reactions and the availability of monomers for the synthesis of
sp
2
-c
linked covalent organic frameworks (COFs) are considerably limited by the irreversibility of the C=C bond. Herein, inspired by the Claisen-Schmidt condensation reaction, two propenone-linked (C=C–C=O) COFs (named Py-DAB and PyN-DAB) are developed based on the base-catalyzed nucleophilic addition reaction of ketone-activated
α
-H with aromatic aldehydes. The introduction of propenone structure endows COFs with high crystallinity, excellent physicochemical stability, and intriguing optoelectronic properties. Benefitting from the rational design on the COFs skeleton, Py-DAB and PyN-DAB are applied to the extraction of radionuclide uranium. In particular, PyN-DAB shows excellent removal rates (>98%) in four uranium mine wastewater samples. We highlight that such a general strategy can provide a valuable avenue toward various functional porous crystalline materials.
The synthesis of
sp
2
carbon-conjugated covalent organic frameworks is limited to a few reactions and monomers due to the poor irreversibility of carbon double bonds. Here the authors synthesize propenone-linked covalent organic frameworks for the removal of radionuclide uranium from mine wastewater samples.
Journal Article
A new approach to semi-inclusive deep-inelastic scattering with QED and QCD factorization
A
bstract
We present the details of a new factorized approach to semi-inclusive deep-inelastic scattering which treats QED and QCD radiation on equal footing, and provides a systematically improvable approximation to the extraction of transverse momentum dependent parton distributions. We demonstrate how the QED contributions can be well approximated by collinear factorization, and illustrate the application of the factorized approach to QED radiation in inclusive scattering. For semi-inclusive processes, we show how radiation effects prevent a well-defined “photon-nucleon” frame, forcing one to use a two-step process to account for the radiation. We illustrate the utility of the new method by explicit application to the spin-dependent Sivers and Collins asymmetries.
Journal Article
Mechanical Stretch α‐Cyclodextrin Pseudopolyrotaxane Elastomer with Reversible Phosphorescence Behavior
Polyethylene glycol chains in two terminals of the naphthalene functional group are threaded into α‐cyclodextrin cavities to form the pseudopolyrotaxane (NPR), which not only effectively induces the phosphorescence of the naphthalene functional group by the cyclodextrin macrocycle confinement, but also provides interfacial hydrogen bonding assembly function between polyhydroxy groups of cyclodextrin and waterborne polyurethane (WPU) chains to construct elastomers. The introduction of NPR endows the elastomer with enhanced mechanical properties and excellent room temperature phosphorescent (RTP) emission (phosphorescence remains in water, acid, alkali, and organic solvents, even at 160 °C high temperatures). Especially, the reversible mechanically responsive room temperature phosphorescence behavior (phosphorescence intensity increased three times under 200% strain) can be observed in the mechanical stretch and recover process, owing to strain‐induced microstructural changes further inhibiting the non‐radiative transition and the vibration of NPR. Therefore, changing the phosphorescence behavior of supramolecular elastomers through mechanical stretching provides a new approach for supramolecular luminescent materials. A reversible mechanically stretch enhanced organic room temperature phosphorescent elastomer with excellent mechanical properties and ultrastable afterglow emission is constructed by pseudopolyrotaxane (NPR) and waterborne polyurethane matrix, in which NPR is composed of α‐cyclodextrin and naphthalene modified polyethylene glycol. This strain‐induced microstructural changes driven tunable phosphorescence performance of elastomer provides a new approach for the development of luminescent materials.
Journal Article