bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facile Fabrication of Redox‐Responsive Covalent Organic Framework Nanocarriers for Efficiently Loading and Delivering Doxorubicin
Authors: Liu Shuai , Yang Jumin , Guo Ruiwei , Deng Liandong , Dong Anjie , Zhang Jianhua 
Published: January 2020

AbstractCovalent organic frameworks (COFs) as drug delivery systems have shown great promise, but their pharmaceutical applications are often limited by complex building blocks, tedious preparations, irregular shape, and uncontrolled drug release within target cells. Herein, a facile strategy is developed to prepare PEGylated redox‐responsive nanoscale COFs (denoted F68@SS‐COFs) for efficiently loading and delivering doxorubicin (DOX) by use of FDA‐approved Pluronic F68 and commercially available building blocks. The obtained F68@SS‐COFs with controlled size, high stability, and good biocompatibility can not only achieve a very high DOX‐loading content (about 21%) and very low premature leakage at physiological condition but can also rapidly respond to the tumor intracellular microenvironment and efficiently release DOX to kill tumor cells. Considering the readily available raw materials, simple preparation process, and desirable redox‐responsiveness, the strategy provided here opens up a promising avenue to develop well‐defined COFs‐based nanomedicines for cancer therapy.
3.6‐8.1 GHz CMOS balun with 1.8° in‐band phase difference by using capacitive balance compensation technique
Authors: Yang Geliang , Tang Kai , Wang Zhigong 
Published: January 2020

AbstractIn this letter, a passive ultra‐wideband balun with high balance performance is proposed. The balun is realized by using a pair of planar spiral coupled transmission lines and a capacitor which is responsible for the capacitive balance compensation. The straight‐forward scattering matrix derivation shows that the proposed structure can achieve full output balances both in amplitude and phase. For demonstration, two baluns with and without the compensating capacitor were designed and fabricated in a 65‐nm complementary metal‐oxide‐semiconductor (CMOS) process. The measured results show that the compensated balun features a measured insertion loss ≤5.2 dB and a return loss ≥10 dB from 3.6 to 8.1 GHz. Within such a wide frequency range, the measured amplitude and phase difference are ≤0.2 dB and 1.8°, respectively, which are much better than its uncompensated counterpart.
Workshop für junge Naturwissenschaftler in Hammamet
Authors: Limbach Hans‐Heinrich , Ellouze Mohamed , Hopf Henning 
Published: January 2020

AbstractBereits zum achten Mal gab es einen Workshop für junge Wissenschaftler aus arabischen Ländern, den GDCh und Alexander‐von‐Humboldt‐Stiftung unterstützten. Dieses Mal fand die zweitägige Veranstaltung Ende Oktober in Hammamet, Tunesien, statt, im Vorfeld des Humboldt‐Kollegs Research to Applications & Markets.
Julius Adolph Stöckhardt: Festakt und Kulturdenkmal
Authors: Wienhaus Otto 
Published: January 2020

AbstractDie seit 1886 auf dem Friedhof Tharandt befindliche Grabstätte eines überragenden (Agrikultur‐)Chemikers des 19. Jahrhunderts – Julius Adolph Stöckhardt – war zu Beginn des Jahres 2019 stark erneuerungsbedürftig. Durch Initiative der TU Dresden, der Stadtverwaltung und der Kirchgemeinde Tharandt ließ sich dieses Kulturdenkmal grundlegend rekonstruieren. Ende September wurde es auf Einladung des Bürgermeisters Silvio Ziesemer eingeweiht.
Was im Block ist, bleibt
Authors: Tomann Rebecca 
Published: January 2020

AbstractDer Blockchain‐Hype ist mittlerweile in die Chemie vorgestoßen. Das Chemie‐ und Pharmaunternehmen Merck patentierte im Frühjahr ein Sicherheitsverfahren, das auf der Technik basiert, und die Bundesregierung beschließt eine Blockchain‐Strategie.
Weniger reisen
Authors: Zbikowski Frauke 
Published: January 2020

AbstractDie Junge Akademie verpflichtet sich, aus Klimaschutzgründen auf Flüge von weniger als 1000 km zu verzichten, und fordert ein Umsteuern bei Dienstreisen in der Wissenschaft.1) Fragen an Akademiemitglied Robert Kretschmer, Juniorprofessor mit Tenure Track für anorganische Chemie in Jena.
Regularized economic model predictive control with barrier functions
Authors: Bitlislioglu Altug , Jones Colin 
Published: January 2020

SummaryIn this article, we consider the use of barrier functions as a regularizing cost in economic model predictive control (EMPC). We focus on a specific variant, EMPC with generalized terminal constraints (G‐EMPC), as it is suitable for tackling large‐scale problems commonly arising in multiagent settings, which motivates our work. The benefits of using barrier functions are providing smoothing of the constrained problem, allowing the use of second‐order methods and warm‐starting, which reduces the iteration count significantly. Apart from these numerical benefits, recentered barrier functions can be used as a regularizing cost in the EMPC problem for enhancing closed‐loop convergence properties. We show that in the case of G‐EMPC, which allows the terminal state to be any equilibrium point, regularizing the problem provides (i) convergence of the predicted terminal state to a neighborhood of a globally optimal equilibrium point, (ii) asymptotic average performance guarantees for the closed‐loop system, and (iii) empirical evidence of accelerated numerical solution of the optimal control problem. Specifically we use a proximal‐like regularization, which penalizes the deviation from the previously predicted trajectories. We analyze system theoretic properties of the proposed scheme and provide simulation examples illustrating the numerical and system theoretical benefits of using barriers.
PCL‐CNT nanocomposites prepared by melt compounding and evaluation of their basic properties
Authors: Lebedev Sergey M. 
Published: January 2020

AbstractPoly(ε‐caprolactone)‐based carbon nanotube composites (PCL‐CNT) fabricated by melt compounding were developed in this work. Complex analysis of main properties of PCL and PCL‐CNT composites was carried out in this study by means of different experimental methods such as dielectric spectroscopy in frequency domain, X‐ray diffraction, DSC analysis, scanning electron and optical microscopy, FTIR analysis, and rheological analysis. It has been found that the percolating threshold for studied composites is observed at 0.1 wt% CNT. The developed PCL‐CNT composites are suitable for processing by extrusion.
Bent into shape: Folded peptides to mimic protein structure and modulate protein function
Authors: Merritt Haley I. , Sawyer Nicholas , Arora Paramjit S. 
Published: January 2020

AbstractProtein secondary and tertiary structure mimics have served as model systems to probe biophysical parameters that guide protein folding and as attractive reagents to modulate protein interactions. Here, we review contemporary methods to reproduce loop, helix, sheet, and coiled‐coil conformations in short peptides.
Redefining Microfabrication of High‐Precision Optics
Authors: Rodríguez Sofía 
Published: January 2020

AbstractIn research, prototyping, and production processes, additive manufacturing has become a tool for unique designs. With the almost unlimited design freedom, intricate geometries and even organic topographies can be created. Nanoscribe's innovative technology of two‐photon grayscale lithography combines an additive approach with maximum precision to rapidly transform digital models into functional parts on the microscale. This maskless lithography technique offers the versatility of additive manufacturing and the precise exposure control of grayscale lithography.
Collision cross‐section analysis of self‐assembled metallomacrocycle isomers and isobars via ion mobility mass spectrometry
Authors: Endres Kevin J. , Barthelmes Kevin , Winter Andreas , Antolovich Robert , Schubert Ulrich S. , Wesdemiotis Chrys 
Published: January 2020

RationaleCoordinatively driven self‐assembly of transition metal ions and bidentate ligands gives rise to organometallic complexes that usually contain superimposed isobars, isomers, and conformers. In this study, the double dispersion ability of ion mobility mass spectrometry (IM‐MS) was used to provide a comprehensive structural characterization of the self‐assembled supramolecular complexes by their mass and charge, revealed by the MS event, and their shape and collision cross‐section (Ω), revealed by the IM event.MethodsSelf‐assembled complexes were synthesized by reacting a bis(terpyridine) ligand exhibiting a 60o dihedral angle between the two ligating terpyridine sites (T) with divalent Zn, Ni, Cd, or Fe. The products were isolated as (Metal2+[T])n (PF6)2n salts and analyzed using IM‐MS after electrospray ionization (ESI) which produced several charge states from each n‐mer, depending on the number of PF6ˉ anions lost upon ESI. Experimental Ω data, derived using IM‐MS, and computational Ω predictions were used to elucidate the size and architecture of the complexes.ResultsOnly macrocyclic dimers, trimers, and tetramers were observed with Cd2+, whereas Zn2+ formed the same plus hexameric complexes. These two metals led to the simplest product distributions and no linear isomers. In sharp contrast, Ni2+ and Fe2+ formed all possible ring sizes from dimer to hexamer as well as various linear isomers. The experimental and theoretical Ω data indicated rather planar macrocyclic geometries for the dimers and trimers, twisted 3D architectures for the larger rings, and substantially larger sizes with spiral conformation for the linear congeners. Adding PF6ˉ to the same complex was found to mainly cause size contraction due to new stabilizing anion–cation interactions.ConclusionsComplete structural identification could be accomplished using ESI‐IM‐MS. Our results affirm that self‐assembly with Cd2+ and Zn2+ proceeds through reversible equilibria that generate the thermodynamically most stable structures, encompassing exclusively macrocyclic architectures that readily accommodate the 60o ligand used. In contrast, complexation with Ni2+ and Fe2+, which form stronger coordinative bonds, proceeds through kinetic control, leading to more complex mixtures and kinetically trapped less stable architectures, such as macrocyclic pentamers and linear isomers.
Self‐Healing of Cracks in Concrete Using Bacillus Strains Encapsulated in Sodium Alginate Beads
Authors: Shahid Saman , Aslam Muhammad A. , Ali Shahid , Zameer Mariam , Faisal Muhammad 
Published: January 2020

AbstractThis research focused on the self‐healing of micro‐cracks in concrete by using different Bacillus strains. The encapsulation of strains in sodium alginate was protected with the bacterial mass, which prevented them from leaching. A viability test was performed to check the viability of bacteria in the highly alkaline environment. The encapsulated bacterial mix having 2–3% of total volume of concrete cubes was effective without compromising compressive strength. The calcium carbonate (CaCO3) precipitation was observed under urease activity. The SEM (Scanning Electron Microscope) revealed the direct involvement of ureolytic bacteria in CaCO3 precipitation. A 16% increase in compressive strength in concrete and significant healing was achieved with Bacillus Subtilis. However, with Bacillus Anthracis, only 6% increase in the concrete strength was achieved. Moreover, the Bacillus Pasteurii did not give effective results. Bacillus Subtilis provided better results than the other strains. The bacterial culture in sodium alginate beads within 2–3% was optimum for compressive strength and self‐healing of cracks.
The Removal of Formaldehyde via Visible Photocatalysis Using the Black TiO2 Nanoparticles with Mesoporous
Authors: Han Lijuan , An Xingcai , Zhang Ping , Jiang Yingyu , Liu Gang 
Published: January 2020

AbstractThe black TiO2 nanoparticles with plentiful mesoporous and active sites was synthesized by a simple calcination amorphous titanium hydroxide in vacuum. The photocatalytic and adsorption performance of the materials for removal of formaldehyde under visible light irradiation was investigated and compared with the white TiO2 nanoparticles according linear and nonlinear forms of pseudo‐first order and pseudo‐second order kinetic equations. The nonlinear of pseudo‐first order is suitable for the photocatalytic and adsorption performance. The reusability performance for formaldehyde shows that the removal rate constants of the black TiO2 in three cycles decline slowly while the white TiO2 declines sharply. The results imply that the black TiO2 nanoparticles have quickly removal rate for formaldehyde and reusability performance. The good photocatalytic and adsorption performance should be result from the mesoporous and oxygen vacancies as active sites. And, the close stacked structure nanoparticles can enhance separation of photogenerated holes and electrons to increase the photocatalytic performance for removal of formaldehyde.
Experimental and Computational Study of Organic Sulfur Removal Proficiency of (Ni, Cu, Co)‐Doped ZIF‐8 Adsorbents
Authors: Saeedirad Raheleh , Ganjali Saeed Taghvaei , Rashidi Alimorad , Bazmi Mansour 
Published: January 2020

AbstractThe synthesis and characterization of a series of metal‐doped ZIF‐8 (metal=Ni, Co and Cu) has been introduced to gain the highly efficient adsorption of dibenzothiophene (DBT) in liquid phase. Under 150 ml DBT/iso‐octane, 100–1700 ppm, and 25–85 °C, the excellent efficiency and reusability in DBT removal was achieved and fitted better with the pseudo‐first order reaction. The maximum adsorption of 191.84 mg S/g for Ni/ZIF‐8 and two steps for intraparticle diffusion study contrary to Cu‐ and Co‐ZIF‐8 suggested the presence of Ni‐HMeIM clusters in ZIF‐8 cavities. Comparing the performance of prepared adsorbents, the order of qmax and PC was the same, i. e. PC Ni/ZIF‐8> PC Cu/ZIF‐8>PC Co/ZIF‐8>PC ZIF‐8 and qmax (Ni/ZIF‐8)> qmax (Cu/ZIF‐8)> qmax (Co/ZIF‐8)> qmax (ZIF‐8) for both 10% and 100% BT. The prepared adsorbents had the FoMs ranging from 0.05‐0.07 that compared to other adsorbents showed the beneficial use for large scale desulfurization process. The endothermic behavior and a homogeneous adsorption was then indicated through thermodynamic and equilibrium studies.
Design, Synthesis, Biological Evaluation and Molecular Dynamic Simulation Studies of Diphenyl Ether Derivatives as Antitubercular and Antibacterial Agents
Authors: Khade Amol B. , Eshwara Vandana K. , Boshoff Helena I.M. , Arora Kriti , Tiwari Ashutosh , Bhat Pritesh , Tiwari Mradul , Shenoy G. Gautham 
Published: January 2020

AbstractTuberculosis is one of the leading cause of death worldwide and Mycobacterium tuberculosis still remains to be the fatal human pathogen. In pursuit of novel diphenyl ethers as antitubercular and antibacterial agents, a series of novel substituted N‐(3‐hydroxy‐4‐phenoxybenzyl)‐N‐phenylmethanesulfonamides 4 a‐k were rationally designed, synthesized and evaluated for their in vitro antitubercular and antibacterial activities. Compounds 4 j and 4 d appeared to be the most promising against Mycobacterium tuberculosis strain H37Rv with minimum inhibitory concentration (MIC) of 42 μM and 65 μM, respectively. Compound 4 j exhibited good in vitro antibacterial activity with MIC of 6.97 μM, 13.94 μM, and 27.88 μM against Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa respectively, indicating it's broad‐spectrum of activity. The safety profile of the compounds was assessed on HepG2, Vero and RAW 264.7 cell lines. Molecular docking and molecular dynamics simulation studies were performed to study the binding behavior of the compounds.
Click‐Derived Uracil‐Appended Organosilatranyl Scaffolds: Synthesis, Antibacterial Characteristics, Pb2+ Binding and Fabrication of Hybrid Silica Nanoparticles
Authors: Singh Gurjaspreet , Sharma Geetika , Sanchita  , Kalra Pooja , Satija Pinky , Pawan  , Singh Baljinder , Aulakh Darpandeep , Wreidt Mario 
Published: January 2020

AbstractUsing a simple biocompatible click route Uracil Allied Organosilatranyl frameworks (4 a–4 e) have been obtained. These uracil tethered silatranes have shown judicious fluorescence as compared to the parent nitrogen heterocycle uracil. Through absorption and fluorescence spectral measurements, it was established that the designed analogues were selective towards Pb2+ recognition. Furthermore, for the first time hybrid silica nanoparticles (U‐SiNPs) containing a uracil bis‐triazole linkage in the silica framework is reported. The fabricated organosilatrane (4 d) was subjected to sol‐gel condensation with silica nanospheres for covalent grafting of the organic functionality on to silica. It was of interest that the uracil immobilized nanoparticles presented a high sensing efficacy towards Pb2+ as compared to the bulk material. Also, to investigate their biological potential, organosilatranes were evaluated against different bacterial strains.
Effect of Calcination Temperature on the Photocatalytic Activity of Nanostructures Synthesized by Hydrothermal Method from Black Mineral Sand
Authors: López‐Vásquez A. , Suárez‐Escobar Andrés , Ramírez J. Herney 
Published: January 2020

AbstractA nanostructured material from black sand, whose structure is composed by Fe2O3 and TiO2 oxides, was prepared via hydrothermal treatment (at 120 °C for 72 h), The starting mineral (as‐synthesized nanostructure) was characterized by XRF spectroscopy and thermogravimetric analysis (TGA/DTA) whereas the calcined nanostructures were analyzed by scanning electron microscopy/EDX, BET single point measurements, X‐ray diffraction, FTIR spectroscopy, and UV‐Vis spectrophotometry. The effect of thermal treatment on structural, morphological and redox properties of nanostructured samples (NS) have been thoroughly studied in the samples calcined at 400, 700 and 1000 °C, together with a non‐treated sample (M1). Their photocatalytic activity toward hydrogen production in the presence of EDTA as sacrificial agent has been tested. The as‐synthetized samples calcined at 1000 °C (NS‐1000) showed a higher photocatalytic activity for hydrogen production, possibly due to the transformation of magnetite into more active photocatalytical phases (hematite) driven by the changes in surface morphology (such as reduction of crystallite and pore size reduction) according to thermal equilibrium of its phases. The highest activity for photocatalytic hydrogen production was achieved by the materials calcined at 1000 °C (M1‐1000 and NS‐1000), while the sample calcined at lower values (<700 °C) were the least active. The catalyst activity was assigned to the appearance of a new active phase (α‐Fe2O3), which improves the electronic mobility during the photocatalytic mechanism.
Enzymeless Electrocatalytic Detection of Uric Acid Using Polydopamine/Polypyrrole Copolymeric film
Authors: Adeosun Waheed A. , Asiri Abdullah M. , Marwani Hadi M. , Rahman Mohammed M. 
Published: January 2020

AbstractUric acid is mainly produced from metabolism of purine nucleotide in human body and have several medical importance in human system. It is therefore very imperative to develop a sensitive and accurate method of its detection. This study aimed to develop uric acid biosensor based on polydopamine/polypyrole (PDA/PPY) composite decorated on glassy carbon electrode. The conductive polymer PDA/PPY was electrochemically synthesized and casted on glassy carbon electrode (GCE). The synthesized PDA/PPY was characterized by fourier transform infrared spectroscopy, field emission scanning electron microscopy, electrochemical impedance spectroscopy, energy dispersive x‐ray spectroscopy and x‐ray photoelectron spectroscopy. PDA/PPY/GCE showed good response towards uric acid with low limit of detection (0.1 μM, S/N =3), good linearity (0.5‐40 μM) and high sensitivity (2.1 μAμMcm−2). It was also found to have stable response for uric acid unaffected by common interferents. Also, when used for uric acid detection in human serum and urine, it showed a good recovery of 90–110%. The developed PDA/PPY composite is proposed as a promising biosensor for uric acid for human health protection.
Design, Synthesis and Selective Functionalization of a Rigid, Truxene Derived Pure Blue‐Emitting Chromophore
Authors: Kaur Banpreet , Karuthedath Safakath , S. P. De Castro Catherine , Laquai Frédéric , Jacob Josemon 
Published: January 2020

AbstractA novel, rigid, solution processable, blue‐emitting chromophore based on an extended core of truxene (ExT) was designed and synthesized. The core, ExT based on a fused cyclic trimer of indenofluorene, was found to be planar in nature and a potential precursor for blue emission. This could be selectively brominated under mild conditions to generate a tribromo derivative which underwent ready Suzuki coupling to generate a trisubstituted pyrene derivative, ExT‐P. This coupling alters the kinetics of the excited state considerably as evident from transient absorption spectroscopy, showing faster singlet state decay and less triplet state formation in the case of the pyrene coupled ExT‐P (∼1.6 ns) compared to ExT (∼17 ns). The ExT‐P shows emission maxima at 441 nm and 442 nm in THF solution and film, respectively, with high PLQY value of 0.97. The negligible bathochromic shift in the solid‐state emission and narrow FWHM suggests practically no aggregation and pure blue emission in the target molecule due to bulky and rigid core.
Enhance Solar‐Light‐Driven Photocatalytic Degradation of Norfloxacin Aqueous Solution by RGO‐Based CdxZn1‐xS Alloy Composite with Band‐Gap Tuneability
Authors: Kar Sayani , Ibrahim Sk , Pal Tanusri , Ghosh Surajit 
Published: January 2020

AbstractThe development of efficient photocatalyst for effective removal of antibiotics from aqueous solution is of great significance to protect the human and aquatic animals from antibiotic‐resistant. Herein, we report the solar light‐responsive photocatalytic activity of CdxZn1‐xS alloy semiconducting nanorods towards the degradation of norfloxacin, which is a widely used for treatment at reverse transcriptase inhibitor Urinary tract infection / respiratory tract infections and hospital‐acquired infections. The Cd0.8Zn0.2S alloy nanorod photocatalyst shows the highest photocatalytic activity with 71% degradation efficiency, which increases significantly with high degradation efficiency of 90%, after the formation of composite with RGO (reduced graphene oxide). In the composite, the RGO mats provide a duel role; it acts as a nucleation center as well as solid support for CdxZn1‐xS nanorods. The accountable reactive species for the degradation of norfloxacin are also explored expansively which exhibits that the hole has the most dominating role toward the degradation of norfloxacin. This work paves a simple eco‐friendly green pathway for the efficient removal of antibiotics aquatic pollutants under solar illumination.