bluuebunny/crossref_metadata_2025 huggingface dataset:
Phase 2 study of lenalidomide maintenance for patients with high‐risk acute myeloid leukemia in remission
Authors: Abou Dalle Iman , Kantarjian Hagop M. , Ravandi Farhad , Daver Naval , Wang Xuemei , Jabbour Elias , Estrov Zeev , DiNardo Courtney D. , Pemmaraju Naveen , Ferrajoli Alessandra , Jain Nitin , Wang Sa A. , Jammal Nadya , Borthakur Gautam , Naqvi Kiran , Pelletier Sarah , Pierce Sherry , Andreeff Michael , Garcia‐Manero Guillermo , Cortes Jorge E. , Kadia Tapan M.
Published: January 2021

Background

New drug combinations have led to significant improvements in remission rates for patients with acute myeloid leukemia (AML). However, many patients with high‐risk AML who respond to their initial treatment and are not candidates for allogeneic stem cell transplantation (ASCT) will eventually relapse with poor outcomes.

Methods

In this phase 2 trial, the efficacy of lenalidomide maintenance was evaluated in patients with high‐risk AML who had achieved their first or second remission after induction chemotherapy and at least 1 consolidation cycle and who were not candidates for immediate ASCT. Lenalidomide was given orally at 10 to 20 mg daily on days 1 to 28 of a 28‐day cycle for up to 24 cycles.

Results

A total of 28 patients were enrolled in this study with a median age of 61 years (range, 24‐87 years). The median number of cycles was 8 (range, 1‐24 cycles). Ten patients (36%) completed 24 months of maintenance treatment. With a median follow‐up of 22.5 months (range, 2.6‐55 months), 12 patients (43%) relapsed after a median of 3 months (range, 0.7‐23 months). The median duration of remission for all patients was 18.7 months (range, 0.7‐55.1 months). The 2‐year overall survival and relapse‐free survival rates from the time of enrollment were 63% and 50%, respectively. Overall, lenalidomide was well tolerated; serious adverse events of grade 3 or 4, including rash (n = 5), thrombocytopenia (n = 4), neutropenia (n = 4), and fatigue (n = 2), were observed in 13 patients (46%).

Conclusions

Lenalidomide is a safe and feasible maintenance strategy in patients with high‐risk AML who are not candidates for ASCT, and it has beneficial effects for patients with negative measurable residual disease.
On the Mechanical Properties of Popgraphene‐Based Nanotubes: a Reactive Molecular Dynamics Study
Authors: Brandão W. H. S. , Aguiar A. L. , Ribeiro L. A. , Galvão D. S. , De Sousa J. M.
Published: January 2021

Carbon‐based tubular materials have sparked a great interest in future electronics and optoelectronics device applications. In this work, we computationally studied the mechanical properties of nanotubes generated from popgraphene (PopNTs). Popgraphene is a 2D carbon allotrope composed of 5‐8‐5 rings. We carried out fully atomistic reactive (ReaxFF) molecular dynamics for PopNTs of different chiralities (
and
) and/or diameters and at different temperatures (from 300 up to 1200 K). Results showed that the tubes are thermally stable (at least up to 1200 K). All tubes presented stress/strain curves with a quasi‐linear behavior followed by an abrupt drop of stress values. Interestingly, armchair‐like PopNTs (
) can stand a higher strain load before fracturing when contrasted to the zigzag‐like ones (
). Moreover, it was obtained that Young's modulus (YMod) (750–900 GPa) and ultimate strength (σUS) (120–150 GPa) values are similar to the ones reported for conventional armchair and zigzag carbon nanotubes. YMod values obtained for PopNTs are not significantly temperature‐dependent. While the σUS values for the
showed a quasi‐linear dependence with the temperature, the
exhibited no clear trends.
Magnetohydrodynamic Interface‐Rearranged Lithium Ions Distribution for Uniform Lithium Deposition and Stable Lithium Metal Anode
Authors: Ma Mingming , Dai Chaoqi , Luo Kailin , Li Shun , Chen Jiahe , Li Zhendong , Ren Xiaodi , Wang Deyu , He Haiyong , Dai Mingzhi , Peng Zhe
Published: January 2021

Uneven lithium (Li) electrodeposition hinders the wide application of high‐energy‐density Li metal batteries (LMBs). Current efforts mainly focus on the side‐reaction suppression between Li and electrolyte, neglecting the determinant factor of mass transport in affecting Li deposition. Herein, guided Li+ mass transport under the action of a local electric field near magnetic nanoparticles or structures at the Li metal interface, known as the magnetohydrodynamic (MHD) effect, are proposed to promote uniform Li deposition. The modified Li+ trajectories are revealed by COMSOL Multiphysics simulations, and verified by the compact and disc‐like Li depositions on a model Fe3O4 substrate. Furthermore, a patterned mesh with the magnetic Fe−Cr2O3 core‐shell skeleton is used as a facile and efficient protective structure for Li metal anodes, enabling Li metal batteries to achieve a Coulombic efficiency of 99.5 % over 300 cycles at a high cathode loading of 5.0 mAh cm−2. The Li protection strategy based on the MHD interface design might open a new opportunity to develop high‐energy‐density LMBs.
Avoiding Tacrolimus Underexposure and Overexposure with a Dosing Algorithm for Renal Transplant Recipients: A Single Arm Prospective Intervention Trial
Authors: Francke Marith I. , Andrews Louise M. , Le Hoang Lan , van de Wetering Jacqueline , Clahsen‐van Groningen Marian C. , van Gelder Teun , van Schaik Ron H. N. , van der Holt Bronno , de Winter Brenda C. M. , Hesselink Dennis A.
Published: January 2021

Bodyweight‐based tacrolimus dosing followed by therapeutic drug monitoring is standard clinical care after renal transplantation. However, after transplantation, a meager 38% of patients are on target at first steady‐state and it can take up to 3 weeks to reach the target tacrolimus predose concentration (C0). Tacrolimus underexposure and overexposure is associated with an increased risk of rejection and drug‐related toxicity, respectively. To minimize subtherapeutic and supratherapeutic tacrolimus exposure in the immediate post‐transplant phase, a previously developed dosing algorithm to predict an individual’s tacrolimus starting dose was tested prospectively. In this single‐arm, prospective, therapeutic intervention trial, 60 de novo kidney transplant recipients received a tacrolimus starting dose based on a dosing algorithm instead of a standard, bodyweight‐based dose. The algorithm included cytochrome P450 (CYP)3A4 and CYP3A5 genotype, body surface area, and age as covariates. The target tacrolimus C0, measured for the first time at day 3, was 7.5–12.5 ng/mL. Between February 23, 2019, and July 7, 2020, 60 patients were included. One patient was excluded because of a protocol violation. On day 3 post‐transplantation, 34 of 59 patients (58%, 90% CI 47–68%) had a tacrolimus C0 within the therapeutic range. Markedly subtherapeutic (< 5.0 ng/mL) and supratherapeutic (> 20 ng/mL) tacrolimus concentrations were observed in 7% and 3% of the patients, respectively. Biopsy‐proven acute rejection occurred in three patients (5%). In conclusion, algorithm‐based tacrolimus dosing leads to the achievement of the tacrolimus target C0 in as many as 58% of the patients on day 3 after kidney transplantation.
Validation of a novel method for canine eruption assessment in unilateral cleft lip and palate patients
Authors: Alqahtani Khalid , Shaheen Eman , Shujaat Sohaib , EzEldeen Mostafa , Dormaar Titiaan , de Llano‐Pérula Maria Cadenas , Politis Constantinus , Jacobs Reinhilde
Published: January 2021

Objective

The aim of this study was to propose and validate a three‐dimensional (3D) methodology for the assessment of canine eruption in patients born with unilateral cleft lip and palate (UCLP) following secondary alveolar bone graft (SABG).

Methods and Materials

A total of 10 patients (four females, six males; mean age: 8.8 years) with UCLP who underwent SABG were recruited. Pre‐ and 6‐month post‐operative cone‐beam computed tomography (CBCT) was acquired for all patients. Post‐operative data was registered onto pre‐operative data utilizing voxel‐based registration. Following superimposition, a segmentation process was applied to segment maxillary canine on both cleft and non‐cleft side. Thereafter, translational and rotational changes in canine position were assessed for both cleft and non‐cleft side by two observers.

Results

The intra‐class correlation coefficient (ICC) indicated excellent reliability (≥0.90) with inter and intra‐observer error of less than 0.05 mm. The overall ICC was found to be high for assessing both translational and rotational changes. The mean absolute inter‐ and intra‐observer difference for translational and rotational changes was found to be less than 1 mm and 3°.

Conclusion

The present method was found to be reliable proving to be clinically applicable for assessing maxillary canine eruption changes in both cleft and non‐cleft bone.
Selective Oxidation of 5‐Hydroxymethylfurfural to 2,5‐Diformylfuran by Visible Light‐Driven Photocatalysis over In Situ Substrate‐Sensitized Titania
Authors: Khan Ayesha , Goepel Michael , Kubas Adam , Łomot Dariusz , Lisowski Wojciech , Lisovytskiy Dmytro , Nowicka Ariadna , Colmenares Juan Carlos , Gläser Roger
Published: January 2021

Solar energy‐driven processes for biomass valorization are priority for the growing industrialized society. To address this challenge, efficient visible light‐active photocatalyst for the selective oxidation of biomass‐derived platform chemical is highly desirable. Herein, selective oxidation of 5‐hydroxymethylfurfural (HMF) to 2,5‐diformylfuran (DFF) was achieved by visible light‐driven photocatalysis over titania. Pristine titania is photocatalytically inactive under visible light, so an unconventional approach was employed for the visible light (λ=515 nm) sensitization of titania via a formation of a visible light‐absorbing complex of HMF (substrate) on the titania surface. Surface‐complexation of HMF on titania mediated ligand‐to‐metal charge transfer (LMCT) under visible light, which efficiently catalyzed the oxidation of HMF to DFF. A high DFF selectivity of 87 % was achieved with 59 % HMF conversion after 4 h of illumination. The apparent quantum yield obtained for DFF production was calculated to be 6.3 %. It was proposed that the dissociative interaction of hydroxyl groups of HMF and the titania surface is responsible for the surface‐complex formation. When the hydroxyl groups of titania were modified via surface‐fluorination or calcination the oxidation of HMF was inhibited under visible light, signifying that hydroxyl groups are decisive for photocatalytic activity.
An output capacitor‐less low‐dropout regulator with wide load capacitance and current ranges
Authors: Zhang Zhang , Xu Shu , Wu Hongyuan , Xie Guangjun , Cheng Xin
Published: January 2021

This paper presents an output capacitor‐less low‐dropout regulator (LDO) with wide load capacitance and current ranges. A new Miller compensation technique called multipath double‐nested Miller compensation with Q‐reduction circuit is introduced to extend the ranges of the load capacitance and current. Besides, a multiple small‐gain stages technology is applied to improve the loop gain of the LDO, achieving better management accuracy. The proposed LDO was fabricated in a 130‐nm CMOS process. The measured maximum load capacitance can be extended to 4.7 nF, and the maximum load current is 80 mA. Moreover, the measured line regulation and load regulation are 4 mV/V and 0.154 mV/mA, respectively.
The neural correlates of paternal consoling behavior and frustration in response to infant crying
Authors: Rilling James K. , Richey Lynnet , Andari Elissar , Hamann Stephan
Published: January 2021

Human fathers often form strong attachments to their infants that contribute to positive developmental outcomes. However, fathers are also the most common perpetrators of infant abuse, and infant crying is a known trigger. Research on parental brain responses to infant crying have typically employed passive listening paradigms. However, parents usually engage with crying infants. Therefore, we examined the neural responses of 20 new fathers to infant cries both while passively listening, and while actively attempting to console the infant by selecting soothing strategies in a video game format. Compared with passive listening, active responding robustly activated brain regions involved in movement, empathy and approach motivation, and deactivated regions involved in stress and anxiety. Fathers reporting more frustration had less activation in basal forebrain areas and in brain areas involved with emotion regulation (e.g., prefrontal cortex and the supplementary motor area). Successful consolation of infant crying activated regions involved in both action‐outcome learning and parental caregiving (anterior and posterior cingulate cortex). Overall, results suggest that active responding to infant cries amplifies activation in many brain areas typically activated during passive listening. Additionally, paternal frustration during active responding may involve a combination of low approach motivation and low engagement of emotion regulation.
Hydrologic classification of Tanzanian rivers to support national water resource policy
Authors: Olden Julian D. , Messager Mathis L. , Tharme Rebecca E. , Kashaigili Japhet J. , Munkyala David , Zielinski Lauren , Warner Andrew
Published: January 2021

Classifying rivers into homogeneous categories based on hydrological and/or environmental attributes supports the implementation of environmental flows to sustain aquatic ecosystems and support the resource needs of society. Hydrological classifications provide decision‐makers with a pragmatic number of water management units by grouping individual rivers or river segments expected to exhibit similar biophysical responses to flow alteration. Such classifications are particularly useful across broad geographies and in data‐limited contexts, such as in Tanzania, where the legal requirement to implement environmental flows for all major waterbodies remains constrained by scant data. We present a two‐level hydrological classification of all Tanzanian basins and the Rufiji River Basin. For the Rufiji River Basin, the largest river basin in the country, we performed an inductive classification based on the availability of long‐term time series of daily average discharge. We clustered 28 gauging stations into seven classes according to ecologically relevant hydrological metrics and used boosted classification trees to predict the hydrological class of all 95,909 river segments in the basin based on environmental attributes that influence flow regimes. In the absence of consistent, readily‐available gauged flow data, we conducted a deductive classification of all Tanzanian rivers whereby segments were directly grouped by multivariate similarity using the same environmental attributes. This analysis revealed 10 river classes reflecting the diversity of ecohydrological conditions characterizing the 486,681 river segments draining in and out of Tanzania. The new hydrological classifications presented here provide the foundation to guide implementation of management practices within the water policy framework of Tanzania.
A COMINRES‐QLP method for solving complex symmetric linear systems
Authors: Liu Lijun , Sekiya Kazuaki , Ogino Masao , Masui Koki
Published: January 2021

Solving complex symmetric systems efficiently is a significantly important issue in the applications of electromagnetics since the discretization of the numerical model using the finite element method results in complex symmetric systems when computing the electromagnetic field. However, such complex symmetric systems are usually much more difficult to be solved because of the property of non‐Hermitian. Therefore, efficient numerical methods for the solution of complex symmetric systems are demanded. In this study, we proposed an iterative method called COMINRES‐QLP which is specially designed for complex symmetric linear systems. Moreover, we proposed a new stopping criterion which could be very useful in practical computations when the condition number of the coefficient matrix is unknown.
Recent Development in Defects Engineered Photocatalysts: An Overview of the Experimental and Theoretical Strategies
Authors: Zafar Zaiba , Yi Shasha , Li Jinpeng , Li Chuanqi , Zhu Yongfa , Zada Amir , Yao Weijing , Liu Zhongyi , Yue Xinzheng
Published: January 2021

Recently, defect architectured photocatalysis is proved to be the most versatile choice for high solar to chemical energy conversion processes. Defect engineering strategies are of great demand to effectively tune the electronic microstructure and surface morphologies of semiconductors to boost charge carrier concentration and extend light harvesting capability. This review provides a comprehensive insight to various kinds of defects along with their synthesis procedures and controlling mechanism to uplift photocatalytic activity. In addition, the contribution made by defects and material optimization techniques toward electronic band structure of the photocatalyst, the optimal concentration of defects, the key adsorption processes, charge distribution, and transfer dynamics have been explained in detail. Further, to clarify the relationship between photocatalytic activity and defect states in real, a comprehensive outlook to the versatile photocatalytic applications has been presented to highlight current challenges and future applications. Defect engineering therefore stands as the next step toward advancement in the design and configuration of modern photocatalysts for high efficiency photocatalysis.
The multiple faces of autoimmune/immune‐mediated myocarditis in children: a biopsy‐proven case series treated with immunosuppressive therapy
Authors: Marcolongo Renzo , Rizzo Stefania , Cerutti Alessia , Reffo Elena , Castaldi Biagio , Baritussio Anna , Basso Cristina , Di Salvo Giovanni , Caforio Alida L.P.
Published: January 2021

The role of immunosuppressive therapy (IT) in paediatric autoimmune/immune‐mediated myocarditis remains poorly defined. To explore its role, we present a series of three consecutive paediatric patients with biopsy‐proven, virus negative, autoimmune/immune‐mediated myocarditis, with distinct clinical and pathological features, who have been successfully treated with IT, a 14‐year‐old boy with Loeffler's fibroblastic parietal endomyocarditis, a 6‐year‐old child with celiac disease with chronic active lymphocytic myocarditis, and a 13‐year‐old boy with long‐standing heart failure and active lymphocytic myocarditis. Patients started IT and entered follow‐up between July 2017 and September 2019; the first patient completed IT. IT was associated with a substantial and sustained recovery of cardiac function in our patients, regardless of their heterogeneous clinical and pathological features. Combination IT was well tolerated and enabled tapering and weaning off steroids.
Electrocardiographic features and their echocardiographic correlates in peripartum cardiomyopathy: results from the ESC EORP PPCM registry
Authors: Mbakwem Amam C. , Bauersachs Johann , Viljoen Charle , Hoevelmann Julian , van der Meer Peter , Petrie Mark C. , Mebazaa Alexandre , Goland Sorel , Karaye Kamilu , Laroche Cécile , Sliwa Karen ,   Peripartum Cardiomyopathy Investigators Group
Published: January 2021

Aims

In peripartum cardiomyopathy (PPCM), electrocardiography (ECG) and its relationship to echocardiography have not yet been investigated in large multi‐centre and multi‐ethnic studies. We aimed to identify ECG abnormalities associated with PPCM, including regional and ethnic differences, and their correlation with echocardiographic features.

Methods and results

We studied 411 patients from the EURObservational PPCM registry. Baseline demographic, clinical, and echocardiographic data were collected. ECGs were analysed for rate, rhythm, QRS width and morphology, and QTc interval. The median age was 31 [interquartile range (IQR) 26–35] years. The ECG was abnormal in > 95% of PPCM patients. Sinus tachycardia (heart rate > 100 b.p.m.) was common (51%), but atrial fibrillation was rare (2.27%). Median QRS width was 82 ms [IQR 80–97]. Left bundle branch block (LBBB) was reported in 9.30%. Left ventricular (LV) hypertrophy (LVH), as per ECG criteria, was more prevalent amongst Africans (59.62%) and Asians (23.17%) than Caucasians (7.63%, P < 0.001) but did not correlate with LVH on echocardiography. Median LV end‐diastolic diameter (LVEDD) was 60 mm [IQR 55–65] and LV ejection fraction (LVEF) 32.5% [IQR 25–39], with no significant regional or ethnic differences. Sinus tachycardia was associated with an LVEF < 35% (OR 1.85 [95% CI 1.20–2.85], P = 0.006). ECG features that predicted an LVEDD > 55 mm included a QRS complex > 120 ms (OR 11.32 [95% CI 1.52–84.84], P = 0.018), LBBB (OR 4.35 [95% CI 1.30–14.53], P = 0.017), and LVH (OR 2.03 [95% CI 1.13–3.64], P = 0.017).

Conclusions

PPCM patients often have ECG abnormalities. Sinus tachycardia predicted poor systolic function, whereas wide QRS, LBBB, and LVH were associated with LV dilatation.
Cardiogenic shock teams and centres: a contemporary review of multidisciplinary care for cardiogenic shock
Authors: Moghaddam Nima , van Diepen Sean , So Derek , Lawler Patrick R. , Fordyce Christopher B.
Published: January 2021

Cardiogenic shock (CS) portends high morbidity and mortality in the contemporary era. Despite advances in temporary mechanical circulatory supports (MCS), their routine use in CS to improve outcomes has not been established. Delays in diagnosis and timely delivery of care, disparities in accessing adjunct therapies such revascularization or MCS, and lack of a systematic approach to care of CS contribute to the poor outcomes observed in CS patients. There is growing interest for developing a standardized multidisciplinary team‐based approach in the management of CS. Recent prospective studies have shown feasibility of CS teams in improving survival across a spectrum of CS presentations. Herein, we will review the rationale for CS teams focusing on evidence supporting its use in streamlining care, optimizing revascularization strategies, and patient identification and MCS selection. The proposed structure and flow of CS teams will be outlined. An in‐depth analysis of four recent studies demonstrating improved outcomes with CS teams is presented. Finally, we will explore potential implementation hurdles and future directions in refining and widespread implementation of dedicated cross‐specialty CS teams.
Construction of a Functionalized Selenophene‐Allylidene Ligand via Alkyne Double Action at a Diiron Complex
Authors: De Palo Alice , Zacchini Stefano , Pampaloni Guido , Marchetti Fabio
Published: January 2021

The diiron µ‐vinyliminium compounds [Fe2Cp2(CO)(µ‐CO){µ‐η1:η3‐C3HC2HC1NMe(R)}]CF3SO3 (R = Me, 2a; R = Xyl = 2,6‐C6H3Me2, 2b; Cp = η5‐C5H5) reacted with grey selenium, in the presence of sodium methoxide, to give the corresponding Se‐functionalized derivatives [Fe2Cp2(CO)(µ‐CO){µ‐η1:η3‐C3HC2(Se)C1NMe(R)}], 3a–b, in ca. 50 % yields. The monoiron zwitterionic complex [FeCp(CO){SeC1(NMe2)C2HC3H}], 4, was obtained as a side‐product (31 %) of the reaction leading to 3a. The treatment of 3b with S8/NaOMe afforded the 2‐ferra‐thiophene [FeCp(CO){SC3HC2HC1NMe(Xyl)}], 5, in 49 % yield. The straightforward reactions of 3a with a two‐fold excess of dialkylacetylenedicarboxylates led to functionalized 3‐amino‐selenophenes appended to the diiron frame through a bridging allylidene ligand, [Fe2Cp2(CO)(µ‐CO){µ‐η1:η3‐C7(CO2R)C6(CO2R)C3HC2SeC5(CO2R)C4(CO2R)C1(NMe2)}] (R = Me, 6a; R = Et, 6b; R = tBu, 6c), in approximately 50 % yields. The synthesis of 6a–c is the result of two distinct modes of reactivity exhibited by the alkyne reactant in one pot, i.e. 1,3‐dipolar cycloaddition to C and Se atoms and insertion into Fe‐µ‐alkylidene. All the products were characterized by means of elemental analysis, IR and multinuclear NMR spectroscopy, and the molecular structure of 6a was elucidated by a single‐crystal X‐ray diffraction study.
Cobalt(II), Zinc(II), Iron(III), and Copper(II) Complexes Bearing Positively Charged Quaternary Ammonium Functionalities: Synthesis, Characterization, Electrochemical Behavior, and SOD Activity
Authors: Stojičkov Marko , Sturm Sabrina , Čobeljić Božidar , Pevec Andrej , Jevtović Mima , Scheitler Andreas , Radanović Dušanka , Senft Laura , Turel Iztok , Andjelković Katarina , Miehlich Matthias , Meyer Karsten , Ivanović‐Burmazović Ivana
Published: January 2021

We have synthesized and characterized Co(II) (1), Zn(II) (2), Fe(III) (3) and Cu(II) (4) complexes of 2,2'‐[2,6‐pyridinediylbis(ethylidyne‐1‐hydrazinyl‐2‐ylidene)]bis[N,N,N‐trimethyl‐2‐oxoethanaminium] dichloride (H2LCl2) by NMR, IR, and X‐Band EPR spectroscopy, respectively, as well as by single‐crystal X‐ray structural analysis. H2LCl2 belongs to the class of diacetylpyridine bis(hydrazone) ligands and bears two positively charged quaternary ammonium functionalities. The complexes 1–3 possess a pentagonal‐bipyramidal geometry, whereas 4 has square‐pyramidal geometry. Redox reactivity and SOD activity of the complexes was studied by means of electrochemical measurements in aqueous‐buffer and DMF or DMSO solutions, respectively, as well as by stopped‐flow measurements. Complexes 1–3 do not have SOD activity, whereas 4 exhibits a high catalytic rate constant for the superoxide dismutation, kcat = 1.73 × 107 m–1 s–1 (in MOPS buffer solution of pH = 7.4). The results were discussed in terms of complex redox potentials, electrostatic interactions and their spatial distribution, kinetic lability of metal centers, and stability of peroxo intermediates, respectively.
The Role of Particle Contact in Densification of FLASH Sintered Potassium Sodium Niobate
Authors: Serrazina Ricardo , Senos Ana M. O. R. , Pereira Luis , Dean Julian S. , Reaney Ian M. , Vilarinho Paula M.
Published: January 2021

Potassium sodium niobate, K0.5Na0.5NbO3 (KNN) is a lead‐free piezoelectric with the potential to replace lead zirconate titanate (PZT) in electromechanical applications. Due to its cuboid particle morphology and volatile elements, monophasic and dense ceramics are difficult to obtain via conventional sintering. In this work, isothermal FLASH sintering produced uniformly densified KNN ceramics at 900 °C, 200 °C lower than conventional sintering. Specific surface area (SSA) analysis of pre‐FLASH ceramics revealed that a 30 min isothermal hold at 900 °C, before the application of electric field, increased the contact area between particles and was crucial to promote uniform densification. Finite element modelling (FEM) revealed why density is more uniform when using isothermal heating compared with a constant heating rate, commonly used in FLASH sintering. These results extend our understanding of FLASH sintering and illustrate its relevance for the development of lead‐free piezoelectrics.
A Molecular Octafluoridoneptunate(IV) Anion in (NH4)4[NpF8] and Theoretical Investigations of the [MF8]4– System (M = Th – Bk)
Authors: Scheibe Benjamin , Patzschke Michael , März Juliane , Conrad Matthias , Kraus Florian
Published: January 2021

Olive‐green single crystals of ammonium octafluoridoneptunate(IV), (NH4)4[NpF8], were obtained by converting NpO2 to a green neptunium tetrafluoride hydrate with hydrofluoric acid and subsequent treatment of the fluoride with an aqueous NH4F solution. The crystal structure of the compound was determined by single‐crystal X‐ray diffraction and observed to be isotypic to the uranium analogue. In (NH4)4[NpF8], molecular [NpF8]4– anions, which can either be described as a distorted square‐antiprism or a bicapped trigonal prism, are present which are bound to the NH4+ ions via N–H···F hydrogen bonds. Quantum‐chemical calculations of [MF8]4– anions show that the M–F bonds are highly ionic and the energy differences between different ligand arrangements likely can be overcome by lattice energies of different crystal structures in the solid state.
Exploration of Novel α,ω‐Substituted Diphosphatrisilanes by Combining Experimental Methods and DFT Calculations
Authors: Weinberger Gernot P. , Sommer Florian , Torvisco Ana , Fischer Roland C. , Flock Michaela
Published: January 2021

The novel diphosphatrisilanes {(R2P‐Si(SiMe3)2‐)2‐SiMe2} [R = Ph, H] and the cyclophosphatrisilabutanes {R–PSi3} [R = H, SiMe3] have been prepared via salt metathesis reactions between phosphanides and 2,4‐dihalogenated pentasilanes and characterized via NMR spectroscopy. The experimental results were supported by DFT calculations. Although P–Si bond formation was observed in all cases, the outcome of the reactions varied depending on the nature of ligands on the phosphanides, forming either linear diphosphatrisilanes or cyclic phosphatrisilacyclobutanes. DFT studies were performed to get a better understanding of the reactions. The precursor silanes were fully characterized using NMR spectroscopy and single‐crystal X‐ray diffraction and offer interesting building blocks. In addition, a modified route for the synthesis of P(TMS)3 was successfully carried out, achieving high yields of up to 73 %, circumventing the use of white phosphorus and phosphine gas during the reaction.
Integration of Individual Functionalized Gold Nanoparticles into Nanoelectrode Configurations: Recent Advances
Authors: Karthäuser Silvia , Peter Sophia , Simon Ulrich
Published: January 2021

Chemically synthesized gold nanoparticles (AuNPs) have attracted much interest for application in various technologically relevant fields including nanoelectronics. In this particular research area, the most promising approach to take full advantage of the tunability in size, shape, and ligand composition of nanoparticles is the integration of a well‐defined number of AuNPs into a nanoscale device. This short review highlights recent progress in the introduction of AuNP into nanoelectronic circuitry by means of selected examples, that demonstrate a “proof‐of‐concept”. Synthetic concepts to obtain isotropic and Janus‐like particles as well as lithographic techniques that allow for the fabrication of nanoelectrode structures, which enable the electrical addressing of individual nanoparticles, are presented. A particular focus of this work is the question of how distinct molecular properties can be addressed in a technologically applicable device geometry by controlling the molecular functionalities in the proximity of semiconductor technology.
2D/2D p‐n Heterojunctions of CaSb2O6/g‐C3N4 for Visible Light‐Driven Photocatalytic Degradation of Tetracycline
Authors: Li Yuanyuan , Shen Jinfeng , Quan Wenxuan , Diao Yue , Wu Meijun , Zhang Bin , Wang Yaoqiong , Yang Dingfeng
Published: January 2021

Despite many attempts to build g‐C3N4 based heterojunctions there are currently no systematic guidelines for designing such composites. Herein, we rationally designed and synthesized a novel CaSb2O6/g‐C3N4 2D/2D heterojunction with ideal lattice matching. The as‐synthesized heterojunctions had superior visible light‐driven photodegradation toward tetracycline solution compared with those of pristine g‐C3N4 and CaSb2O6. The corresponding maximum apparent kinetic rate constant was 0.01388 min–1, which was approximately 2.4 and 53 times greater than those of g‐C3N4 and CaSb2O6, respectively. Additionally, photoelectrochemical measurements indicated that the enhanced photocatalytic performance was attributed to generation of an internal electric field by the intimate contact p‐n heterojunction. The main reactive species were ·OH, ·O2– and h– are the dominate reactive species in the photocatalytic process. This study will inspire efforts to build 2D/2D heterojunction photocatalysts with efficient carrier separation and higher photocatalytic performance through structural chemistry or solid state chemistry analysis.
Thermal Treatment of a Keggin‐Type Diplatinum(II)‐Coordinated Polyoxotungstate: Formation of Hydrophilic Colloidal Particles and Photocatalytic Hydrogen Production
Authors: Kato Chika Nozaki , Aono Koki , Kurihara Akihiro , Kubota Toshiya , Kasai Ryota , Suzuki Kosuke
Published: January 2021

Hydrophilic platinum‐polyoxotungstate colloidal particles formed by a self‐assembly of Cs4[{Pt(OH)2}2·SiW12O40] were successfully obtained by calcining a cesium salt of α‐Keggin‐type diplatinum(II)‐coordinated silicotungstate, Cs4[α‐SiW11O39{cis‐PtII(NH3)2}2]·11H2O (Cs‐Si‐Pt), in air at 300 °C. During the thermal treatment, the structure of the mono‐lacunary Keggin‐type silicotungstate ligand {SiW11O39} transformed to that of {SiW12O40}, and the diplatinum sites in Cs‐Si‐Pt transformed to the platinum hydroxides with the elimination of the ammonia molecules coordinated to the platinum sites. All four cesium ions in Cs4[{Pt(OH)2}2·SiW12O40] could be ion‐exchanged by four tetramethylammonium ions, and hydrophilic [(CH3)4N]4[{Pt(OH)2}2·SiW12O40] colloidal particles were also formed in aqueous solution. The calcined sample acted as a photocatalyst for hydrogen evolution from aqueous triethanolamine (TEOA) under visible light irradiation (λ = ≥440 nm) in the presence of Eosin Y, K5[α‐SiW11{Al(OH2)}O39]·7H2O, and titanium dioxide. Although relatively rapid deactivation was observed, the turnover frequency was 3588 h–1 after 20 min, and the turnover number exceeded 4600 after 3 h of light irradiation.
Acetylacetonate and Acetate Complexes of Nickel(II) Catalyse the Air Oxidation of Phosphines
Authors: Hansen Line Sofie , Jakobsen Vibe Boel , McKee Vickie , McKenzie Christine J.
Published: January 2021

The polymeric complex trans‐[Ni(acac)2(µ2‐dppe)]n·2MeCN {1a, dppe = 1,2‐ethylenebis(diphenylphosphine)} is sometimes transiently deposited from the reaction of [Ni(acac)2] with dppe in MeCN prior to its facile onwards air oxidation to final crystallization of a doubly‐oxygenated relative, cis‐[Ni(acac)2(µ2‐dppeO2)]n {2, dppeO2 = 1,2‐ethylenebis(diphenylphosphineoxide)}. A similar unsolvated phase of the initial polymer, trans‐[Ni(acac)2(µ2‐dppe)]n (1b), can be isolated from toluene. The oxidation of dppe by O2 is catalytic and dppeO2 was isolated in close to stoichiometric yields from solutions containing 5 % Ni(acac)2 relative to dppe. The reaction rate slows after a few turnovers due to inhibition by the product. The relative yields of dppeO2 are higher than those from catalytic air oxidation of methyldiphenylphosphine and triphenylphosphine and we speculate that a pathway for this reaction involves a dimetallic cooperativity enabled specifically by dppe.
Efficient Stereoselective Synthesis and Optical Properties of Heteroleptic Square‐Planar Platinum(II) Complexes with Bidentate Iminopyrrolyl Ligands
Authors: Inoue Ryo , Morisaki Yasuhiro
Published: January 2021

Heteroleptic platinum(II) complexes find wide application in supramolecular and photochemistry. Nevertheless, efficient methods for their preparation are limited. Herein, we report a novel synthetic approach toward heteroleptic trans‐bis(iminopyrrolyl)Pt(II) complexes with N‐propyl, ‐pentyl, ‐methoxyethyl, and ‐phenyl substituents using a Zeise's dimer analog as the platinum source. The developed route, which consists of two sequential complexation reactions with the corresponding sodium salt of the iminopyrrolyl ligand, is operationally simple and delivered the mono and trans‐bis coordinated products quantitatively and highly stereoselectively. The obtained Pt(II) complexes exhibited crystallization‐induced phosphorescent emission enhancement behavior. Furthermore, the luminescence properties were dependent on the substituents on the nitrogen atoms of the iminopyrrolyl ligands. Hence, this study is expected to have important implications in the fields of supramolecular and photochemistry.
The Heteroleptic Cluster Cation [(W6I8)I3(CH3CN)3]+
Authors: Pachel Florian , Händel Jacqueline , Ströbele Markus , Meyer Hans‐Jürgen
Published: January 2021

The iodide‐rich compound [(W6I8)I3(CH3CN)3]I9 was synthesized solvothermally from W6I22 and I2 in acetonitrile. The refined crystal structure reveals the presence of the novel heteroleptic cluster cation [(W6I8)I3(CH3CN)3]+ containing the [W6I8]4+ cluster with an octahedral tungsten cluster core, coordinated by three apical iodido and three acetonitrile ligands via cluster vertices. The iodide‐rich starting material W6I22 with the addition of I2, produces the heptaiodide ion (I7)– that is present in the structure of [(W6I8)I3(CH3CN)3](I7)·I2. The novelty of this compound is based on the cationic nature of the [(W6I8)I3(CH3CN)3]+ cluster after anionic [(W6I8)I6]2– clusters and their ligand (L) substituted derivatives [(W6I8)L6]2– have been widely reported for their versatile photophysical properties.
Study of Donor–Acceptor Bonds on the N‐Coordinated Sn/Pb(II) Atoms in peri‐Substituted Naphthalenes: Evidence of Pb→B Interaction
Authors: Aman Michal , Dostál Libor , Mikysek Tomáš , Růžičková Zdenka , Mebs Stefan , Beckmann Jens , Jambor Roman
Published: January 2021

Peri‐substituted naphthalene derivatives, namely, N‐coordinated plumbylenes 1‐PPh2‐8‐PbL‐C10H6 (4) and 1‐BCy2‐8‐PbL‐C10H6 (5) (L = 2,6‐(Me2NCH2)2C6H3) were prepared. Compounds 4 and 5 allowed studying interactions between the Pb atoms with the either Lewis acidic (BCy2) or Lewis basic sites (PPh2). Addition of an external Lewis acid (BH3·SMe2) to 5 provided the complex 1‐BCy2‐8‐[(BH3)2L]Pb‐C10H6 (7), in which both NMe2 groups of the ligand L were coordinated by BH3. This reaction has also been used for the synthesis of a tin analogue 1‐BCy2‐8‐[(BH3)2L]Sn‐C10H6 (6). New complexes 4–7 were also compared with the previously known, tin(II) analogues 1‐PPh2‐8‐SnL‐C10H6 (1), 1‐PPh2‐8‐[(BH3)2L]Sn‐C10H6 (2), 1‐BCy2‐8‐SnL‐C10H6 (3). This set of compounds allowed us to study influence of the P→E and E→B peri‐contacts upon the redox potentials E1/2 (ox1) by the cyclic voltammetry. As the result, the selective oxidation of E(II) atom was also studied and the new organotin(IV) sulfide [1‐PPh2‐8‐LSn(C10H6)(µ‐S)]2 (9) was prepared, the product of exclusive oxidation of the tin(II) atom in 1. Beside this, the evaluation of the P→E and E→B peri‐contacts in the neutral molecules, the first and second ionization energies (IE) were calculated. For this reason, electronic properties, full structural optimizations were conducted with density functional theory (DFT) for all possible combinations of metal atom (Sn vs. Pb), Lewis acid (N→Sn/Pb vs. N(BH3)Sn/Pb), peri‐substituents (BCy2 vs. PPh2), and for three molecular charges (0 vs. 1+ vs. 2+) on the B3PW91/6‐311+g(2df,p) level of theory.
Structure and Magnetic Properties of Sr2NaOsO6
Authors: Thakur Gohil S. , Felser Claudia , Jansen Martin
Published: January 2021

Sr2NaOsO6, an ordered double perovskite, was obtained by solid‐state synthesis. The compound crystallizes in a monoclinic cell [P21/n, a = 5.7043(1) Å, b = 5.7828(1) Å, c = 8.0816(2) Å; β = 90.01(2)°] and develops long‐range antiferromagnetic order at ≈ 17 K with strong canting generating a tiny spontaneous moment of 0.06 µB/Os ion. A fit of the high temperature susceptibility data according to a modified Curie–Weiss law revealed a small effective paramagnetic moment of 0.7 µB/Os, which underlines the substantial effect of spin‐orbit coupling in 5d oxides. A broad instead of a sharp lambda anomaly in specific heat data suggests frustration and strong magnetic disorder at the osmium lattice.
Hybrid Inorganic‐Organic Photochromic Film Based on Polymolybdate and Isoniazid Dimer: Synthesis, Structure, and Photochromism
Authors: Wang Yang , Huang Xinjun , Zhao Qin , Shi Litong , Sun Xiaodong , Wu Shuyao , Jiang Yuchun , Song Xi‐Ming , Zhang Yu , Ma Tianyi
Published: January 2021

A photochromic film based on an inorganic‐organic hybrid, Na3H(H2O)2[β‐Mo8O26](C12H8N4O2)2·19H2O (1), is developed for the first time. Compound 1 was in situ synthesized and structurally characterized by single‐crystal X‐ray crystallography, and a dimerization reaction of isoniazid can be directly observed during the synthesis process. Together with the polymolybdate, the azo bond in the dimerization product N,N'‐bis(isonicotinamide) hydrazide showed photochromic properties under illumination, widening the light absorption range of polymolybdate. Irradiation experiments of the prepared film indicated an excellent waterproof and recyclable layered material, which demonstrated a distinctive way of extending the application of polyoxometalate based hybrid inorganic‐organic functional materials in the field of photocatalysis.
A2BBi2(PO4)2(P2O7) (A = K, Rb, B = Pb, Cd): the Effect of Cation Sizes on Structural Evolution
Authors: Qi Lu , Chen Zhaohui , Li Lu , Jing Qun , Li Na , Jiang Zhongqi , Dong Xiaoyu , Lee Ming‐Hsien
Published: January 2021

Two homologous new mixed‐metal phosphates K2PbBi2(PO4)2(P2O7) (I) and Rb2CdBi2(PO4)2(P2O7) (II) were successfully synthesized in A2BBi2(PO4)2(P2O7) (A = K, Rb, B = Pb, Cd) system through the traditional high‐temperature solid‐phase method. The single crystal structures of the two compounds are shown to be the unique three‐dimensional (3D) framework composed of different types of layers, but not isomorphic. We compared series compounds A2PbBi2(PO4)2(P2O7) (A = K, Rb, Cs), which are isomorphic and crystallize in the same space group Pnma. It is noteworthy that they are distinct different in degree of structural disorder, which is tuned by A‐site cations. The effect of A‐site cations is recognized by analyzing the disorder degree in three related structures and other available 182 mixed‐metal phosphates. To the best of our knowledge, such structural analysis is rarely reported in inorganic phosphates and the cation modulation strategy can be used to guide structural disorder according to the difference‐value (D‐value) of cation radii. Furthermore, the syntheses, thermal analysis, relevant spectroscopic measurements and theoretical calculations for I and II compounds were also discussed.
Tetranuclear Lanthanide Complexes Supported by Hydroxyquinoline‐Calix[4]arene‐Ligands: Synthesis, Structure, and Magnetic Properties of [Ln4(H3L)2(µ‐OH)2(NO3)4] (Ln = Tb, Dy, Yb) and [Dy2(H4L)2(NO3)](NO3)
Authors: Jäschke Astrid , Stumpf Thorsten , Aliabadi Azar , Büchner Bernd , Kataev Vladislav , Hahn Torsten , Kortus Jens , Kersting Berthold
Published: January 2021

The coordination behavior of the calixarene‐based N4O4 donor ligand H6L bearing two pendant 8‐hydroxyquinoline‐2‐hydrazone arms towards the lanthanide ions Tb3+, Dy3+, and Yb3+ has been investigated. H6L was found to support tetra‐ and dinuclear mixed‐ligand complexes with the pendant hydrazone units in a deprotonated enolate and/or a neutral amide form. The direct reaction of H6L with Ln(NO3)3(H2O)6 and NEt3 in a 1:1:2 molar ratio leads to tetranuclear [Ln4(H3L)2(µ‐OH)2(η2‐NO3)4] complexes {Ln = Tb (1), Dy (2), Yb (3)} containing a rectangular arrangement of four eight‐coordinate Ln3+ ions bridged by two hydroxido‐ and four quinolinolato‐O atoms as established by X‐ray crystallography. Degradation of 2 occurs upon addition of further equiv. of H6L to give dinuclear [Dy2(H4L)(NO3)2(MeCN)2]NO3 (4) with eight‐ and ten‐coordinated Dy3+ ions. ESI‐MS studies reveal that such dinuclear species exist also in the solution state. The results of variable temperature direct and alternating current magnetic susceptibility measurements for 1–4 and high frequency EPR study on 4 are also reported.
Hydrosilylation and Hydrogermylation of CO2 and CS2 by Al and Ga Functionalized Silanes and Germanes – Cooperative Reactivity with Formation of Silyl Formates and Disilylacetals
Authors: Tolzmann Michael , Schürmann Lina , Hepp Alexander , Uhl Werner , Layh Marcus
Published: January 2021

Hydrometallation of the alkynylelement hydrides iPr2E(H)–C≡C‐tBu (1; E = Si, Ge) with R2M–H [M = Al, Ga; R = tBu, CH(SiMe3)2] afforded in moderate yields the Al and Ga functionalized alkenylsilanes and ‐germanes iPr2E(H)C(MR2)=CH‐tBu (2). The air and moisture sensitive Al compounds reacted with CO2 under mild conditions (room temperature, 1 bar) to yield the formates [iPr2EC(AlR2)=C(H)–tBu]O2CH (3) by C=O insertion into the E–H bond and coordination of the second O atom to aluminum. The acetal MeAl[C(SiiPr2)=CH‐tBu]2O2CH2 (4a) was obtained as a unique side‐product. The less Lewis acidic Ga compound 2c did not react with CO2 even at higher temperature and pressure. Reaction with CS2 yielded the dithioacetals [iPr2EC(MtBu2)=CH‐tBuS]2CH2 (6) by reduction of both C=S bonds. Compounds 6 have two ECMS heterocycles bridged by a CH2 group. The reaction of the Ga compound 2c required elevated temperature (40 °C). At 70 °C the formal elimination of H2C=CMe2 and “CH4” afforded the unusual gallium sulfide {iPr2SiC[Ga(tBu)(µ‐S)]=CH‐tBu}2 (7c) which crystallized as a dimer with a central Ga2S2 heterocycle that is joined via its Ga–S edges to two four‐membered GaSCSi heterocycles.
A Facile Electrosynthesis of Terephthalate (tp)‐Based Metal‐Organic Framework, Ni3(OH)2(H2O)2(tp)2 with Superior Catalytic Activity for Hydrogen Evolution Reaction
Authors: Liu Li , Hai Yang , Gong Yun
Published: January 2021

Utilizing a facile one‐step electrodeposition method, several terephthalate (tp)‐based MOFs, M3(OH)2(H2O)2(tp)2 (M = Ni, Co or Fe) have been synthesized on Ni foam (NF) or carbon cloth (CC). Among the MOFs, Ni‐MOF/NF shows porous nanosheet arrays on NF and exhibits extraordinary hydrogen evolution reaction (HER) catalytic activity with an overpotential (η10) of 60 mV to reach a current density of –10 mA cm–2, which is superior to Co‐MOF/NF (η10 = 184 mV) and Fe‐MOF/NF (η10 = 203 mV), and even comparable to Pt/C (η10 = 23 mV), indicating the HER performance is associated with the species of metal ions and the morphology. In addition, it is primarily investigated the formation mechanism of Ni‐MOF nanosheet arrays on Ni foam. Furthermore, Ni‐MOF/NF can endure 50 h‐electrolysis test at –20 mA cm–2 in alkaline condition. Density functional theory (DFT) calculations identify the active site of Ni3(OH)2 (H2O)2(tp)2 for HER is the O‐site from the coordinated ‐OH group (ΔGH=–0.40 eV) rather than the O‐site from the coordinated H2O molecule (ΔGH = –1.75 eV).
s‐ and p‐Block Dinuclear Metal(loid) Complexes Bearing 1,4‐Phenylene and 1,4‐Cyclohexylene Bridged Bis(amidinate) Ligands
Authors: Garg Palak , Dange Deepak , Jones Cameron
Published: January 2021

Treating two 2,6‐diisopropylphenyl (Dip) substituted, 1,4‐phenylene or 1,4‐cyclohexylene bridged, bis(amidine)s, viz. C6Hn{[Dip(H)N](DipN=)C}2‐1,4 (n = 4 (PhAmid2H2) or 10 (CyAmid2H2)), with groups 1 and 2 alkyl complexes, proceeded via alkane elimination and the formation of the lithium and magnesium bis(amidinate) complexes, [{(THF)2Li}2(µ‐PhAmid2)], [{(THF)3K(µ‐PhAmid2)K}∞], [(Et2O)IMg(µ‐PhAmid2)MgI(OEt2)2], and [{(Et2O)2IMg}2(µ‐CyAmid2)]. The crystal structures of the complexes reveal variable modes of coordination at the metal centre. Two lithium bis(amidinate) compounds have been utilized in salt elimination reactions with group 13 and 14 halides, yielding a series of bis(amidinato) aluminum(III), silicon(IV), germanium(II) and tin(II) halide complexes, viz. [(I2Al)2(µ‐PhAmid2)], [(X3Si)2(µ‐PhAmid2)] (X = Cl, Br or Cl/H), [(ClM)2(µ‐PhAmid2)] (M = Ge or Sn), and [(ClGe)2(µ‐CyAmid2)]. Attempts to reduce the bis(amidinato) metal(loid) halide complexes with a series of s‐block metal reducing agents have been carried out, with the aim of obtaining dinuclear or polymeric bis(amidinato) metal(I) systems. However, these reductions typically led to intractable mixtures of products. In other attempted reductions, treating [(Cl2HSi)2(µ‐PhAmid2)] with two N‐heterocyclic carbenes (NHCs), :C{(RNCMe)2} (R = Me (TMC) or Pri (IPrIMe)) led to single dehydrochlorination reactions, affording the cyclohexa‐2,5‐diene‐1,4‐diylidene bridged bis(diamide) silicon(IV) complexes, [{(NHC)Cl2Si}{µ‐(DipN)2C=(C6H4)=C(NDip)2}{SiHCl(NHC)}] (NHC = TMC or IPrIMe), in which the bis(amidinate) ligand has been transformed into a tetra(amide).