Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 105
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nat Mater ; 23(4): 570-576, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38297141

RESUMO

Soft building blocks, such as micelles, cells or soap bubbles, tend to adopt near-spherical geometry when densely packed together. As a result, their packing structures do not extend beyond those discovered in metallic glasses, quasicrystals and crystals. Here we report the emergence of two Frank-Kasper phases from the self-assembly of five-fold symmetric molecular pentagons. The µ phase, an important intermediate in superalloys, is indexed in soft matter, whereas the ϕ phase exhibits a structure distinct from known Frank-Kasper phases in metallic systems. We find a broad size and shape distribution of self-assembled mesoatoms formed by molecular pentagons while approaching equilibrium that contribute to the unique packing structures. This work provides insight into the manipulation of soft building blocks that deviate from the typical spherical geometry and opens avenues for the fabrication of 'soft alloy' structures that were previously unattainable in metal alloys.

2.
Proc Natl Acad Sci U S A ; 119(29): e2205636119, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858302

RESUMO

Second-order optical nonlinearity is the essential concept for realizing modern technologies of optical wavelength conversion. The emerging helical polarization fluid, dubbed helielectric nematic, now makes it possible to design and easily fabricate various polarization structures and control their optical responses. The matter family is demonstrated as an ideal liquid platform for nonlinear optical conversion and amplification with electric-reconfigurable tunability. We here develop a universal phase matching theory and reveal a nonclassic chirality-sensitive phase-matching condition in the polarization helices through both the numerical calculation and the experimental validations. The nonlinear optical amplification can be dramatically modulated with a contrast ratio of >100:1 by an in-plane electric field. Furthermore, we employ the director relaxation under electric fields coupled with nonlinear optical simulation to clarify the topology-light interactions.

3.
Proc Natl Acad Sci U S A ; 119(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35022240

RESUMO

The quasiperiodic structures in metal alloys have been known to depend on the existence of icosahedral order in the melt. Among different phases observed in intermetallics, decagonal quasicrystal (DQC) structures have been identified in many glass-forming alloys yet remain inaccessible in bulk-state condensed soft matters. Via annealing the mixture of two giant molecules, the binary system assemblies into an axial DQC superlattice, which is identified comprehensively with meso-atomic accuracy. Analysis indicates that the DQC superlattice is composed of mesoatoms with an unusually broad volume distribution. The interplays of submesoatomic (molecular) and mesoatomic (supramolecular) local packings are found to play a crucial role in not only the formation of the metastable DQC superlattice but also its transition to dodecagonal quasicrystal and Frank-Kasper σ superlattices.

4.
Soft Matter ; 20(16): 3392-3400, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38619075

RESUMO

The recent discovery of ferroelectric nematics provides new opportunities for exploring polar topology in liquid matter. Here, we report numerous potential polarization topological states (e.g., polar vortex-like and line disclination mediated structures) in confined ferroelectric nematics with similar free-energy levels. In the experiment, they appear according to the confinement size and surface anchoring conditions. Based on a minimal analytical approach, we reveal that the topological transformation is balanced among the nematic elasticity, the polarization gradient, the flexoelectric and the depolarization interactions.

5.
Phys Chem Chem Phys ; 26(16): 12422-12432, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38619386

RESUMO

In traditional chiral nematic liquid crystals, the apolar cholesterics, the dielectric effect is the main driving force for responding to an electric field. The emerging polar chiral nematics, dubbed helielectric nematics, are the polar counterparts of the cholesterics. The head-to-tail symmetry breaking of the new matter state enables it to respond sensitively to the polarity of an electric field. Here, we report on the observation of a sequential polar winding/unwinding process of polarization helices under an electric field applied perpendicular to the helical axes, which behaves distinctly from the unwinding of the apolar cholesteric helices. Understanding the helix-unwinding behaviors provides insights for developing switchable devices based on helielectric nematics.

6.
Proc Natl Acad Sci U S A ; 118(42)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34642251

RESUMO

Recently, a type of ferroelectric nematic fluid has been discovered in liquid crystals in which the molecular polar nature at molecule level is amplified to macroscopic scales through a ferroelectric packing of rod-shaped molecules. Here, we report on the experimental proof of a polar chiral liquid matter state, dubbed helielectric nematic, stabilized by the local polar ordering coupled to the chiral helicity. This helielectric structure carries the polar vector rotating helically, analogous to the magnetic counterpart of helimagnet. The helielectric state can be retained down to room temperature and demonstrates gigantic dielectric and nonlinear optical responses. This matter state opens a new chapter for developing the diverse polar liquid crystal devices.

7.
Sensors (Basel) ; 24(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38894445

RESUMO

The detection of seismic activity precursors as part of an alarm system will provide opportunities for minimization of the social and economic impact caused by earthquakes. It has long been envisaged, and a growing body of empirical evidence suggests that the Earth's electromagnetic field could contain precursors to seismic events. The ability to capture and monitor electromagnetic field activity has increased in the past years as more sensors and methodologies emerge. Missions such as Swarm have enabled researchers to access near-continuous observations of electromagnetic activity at second intervals, allowing for more detailed studies on weather and earthquakes. In this paper, we present an approach designed to detect anomalies in electromagnetic field data from Swarm satellites. This works towards developing a continuous and effective monitoring system of seismic activities based on SWARM measurements. We develop an enhanced form of a probabilistic model based on the Martingale theories that allow for testing the null hypothesis to indicate abnormal changes in electromagnetic field activity. We evaluate this enhanced approach in two experiments. Firstly, we perform a quantitative comparison on well-understood and popular benchmark datasets alongside the conventional approach. We find that the enhanced version produces more accurate anomaly detection overall. Secondly, we use three case studies of seismic activity (namely, earthquakes in Mexico, Greece, and Croatia) to assess our approach and the results show that our method can detect anomalous phenomena in the electromagnetic data.

8.
Anal Chem ; 95(21): 8239-8249, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37199694

RESUMO

It is difficult to distinguish between H2O and D2O due to their very similar properties. Triphenylimidazole derivatives with carboxyl groups (TPI-COOH-2R) show intramolecular charge transfer that responds to polarities and pH of solvents. Here, a series of TPI-COOH-2R with very high photoluminescence quantum yields (73-98%) were synthesized to distinguish D2O from H2O by the method of wavelength-changeable fluorescence. In a mixed THF/water solution, the increase of H2O and D2O contents will separately induce different pendulum-type fluorescence variations and form plots of closed circles with the same starting and ending points from which a THF/water ratio that displays the most different emission wavelengths (up to 53 nm with an LOD of 0.064 vol %) can be determined to further distinguish D2O from H2O. This is proved to be originated from the various Lewis acidities between H2O and D2O. The results of theoretical calculations and experiments suggest that, for different substituent groups in TPI-COOH-2R, an appropriate electron-donating effect is beneficial to distinguish between H2O and D2O, while the electron-pulling effect is adverse. Moreover, because the potential hydrogen/deuterium exchange does not affect the as-responsive fluorescence, this method is reliable. And this work provides a new strategy for the design of fluorescent probes for D2O.

9.
Blood ; 138(20): 1928-1938, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34314483

RESUMO

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by uncontrolled terminal complement activation and subsequent intravascular hemolysis (IVH). C5 inhibitors prevent membrane attack complex formation, but patients may experience extravascular hemolysis (EVH) and continue to require blood transfusions. Danicopan, an oral proximal complement inhibitor of alternative pathway factor D (FD), is designed to control IVH and EVH. In a phase 2 dose-finding trial, eculizumab-treated transfusion-dependent patients with PNH (n = 12) received danicopan, 100 to 200 mg thrice daily, in addition to their eculizumab regimen for 24 weeks. End points included hemoglobin (Hgb) change vs baseline at week 24 (primary), reduction in blood transfusions, and patient-reported outcomes. Safety, tolerability, and pharmacokinetics/pharmacodynamics were measured. Twelve patients received ≥1 danicopan dose; 1 patients discontinued from a serious adverse event deemed unlikely related to danicopan. Eleven patients completed the 24-week treatment period. Addition of danicopan resulted in a mean Hgb increase of 2.4 g/dL at week 24. In the 24 weeks prior to danicopan, 10 patients received 31 transfusions (50 units) compared with 1 transfusion (2 units) in 1 patient during the 24-week treatment period. Mean Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score increased by 11 points from baseline to week 24. The most common adverse events were headache, cough, and nasopharyngitis. Addition of danicopan, a first-in-class FD inhibitor, led to a meaningful improvement in Hgb and reduced transfusion requirements in patients with PNH who were transfusion-dependent on eculizumab. These benefits were associated with improvement of FACIT-Fatigue. This trial was registered at www.clinicaltrials.gov as #NCT03472885.


Assuntos
Aminopiridinas/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Inativadores do Complemento/uso terapêutico , Hemoglobinúria Paroxística/tratamento farmacológico , Indazóis/uso terapêutico , Prolina/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Aminopiridinas/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Inativadores do Complemento/efeitos adversos , Feminino , Humanos , Indazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prolina/efeitos adversos , Pirimidinas/efeitos adversos , Resultado do Tratamento , Adulto Jovem
10.
Macromol Rapid Commun ; 44(1): e2200246, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35526256

RESUMO

Lithium-sulfur (Li-S) batteries with high sulfur utilization, long-cycle life, and dendrite-free features hold great promise for the development of next-generation energy storage devices of high energy density. Considerable efforts have been committed to solving the polysulfide shuttle problem toward highly stable Li-S batteries. Here, a unique polymer network containing dually anchored ionic liquids (DA-PIL) is devolped to improve the cycling performance and coulombic efficiency of Li-S batteries. This DA-PIL electrolyte incorporates the amphiphilicity of both the polysulfides anion and lithium cation, creating an ionic function layer on polypropylene separator. Noteworthily, the DA-PIL network is "clean" in the sense that no free ionic specifies are introduced to the electrolyte system. The DA-PIL layer not only enables strong supression against polysulfide shuttling but simultaneously allows fast lithium transportation owing to cooperate electrostatic interaction among anchored cations and anions. The DA-PIL layer functionalized on a polypropylene separator can boost excellent stability of Li-S battery with >1600 h cycling test at 0.25 mA cm-2 . The Li-S cell with DA-PIL layer delivers a higher discharge capacity of 827.4 mAh g-1 at 1C. A discharge capacity of 630.6 mAh g-1 is retained after 1000 cycles.


Assuntos
Líquidos Iônicos , Lítio , Polipropilenos , Polímeros , Enxofre
11.
J Chem Phys ; 159(18)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37947513

RESUMO

A great deal of effort has been recently devoted to the study of dielectric relaxation processes in ferroelectric nematic liquid crystals, yet their interpretation remains unclear. In this work, we present the results of broadband dielectric spectroscopy experiments of a prototypical ferroelectric nematogen in the frequency range 10 Hz-110 MHz at different electrode separations and under the application of DC bias fields. The results evidence a complex behavior in all phases due to the magnitude of polar correlations in these systems. The observed modes have been assigned to different relaxation mechanisms based on existing theoretical frameworks.

12.
Surg Innov ; 30(2): 261-270, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35734985

RESUMO

BACKGROUND: As the 2019 Coronavirus Disease (COVID-19) repeated, the prevention and treatment will be normalized in a period. "Large number of patients" and " Turnover quickly" of the day surgery ward greatly increased the difficulty of policy formulation and implementation. The normalization also had a huge negative psychological impact on patients/family members. This study aims to introduce effective epidemic prevention and control measures in day surgery wards, and to clarify the influencing factors of anxiety and subjective discomfort of patients and their families during the normalization of COVID-19. METHODS: To prepare for normalization of epidemic, research discuss improvements in the management of staff, environment, process. A total of 148 patients admitted to West China Hospital from December 2021 to March 2022 and their relatives were asked to complete a questionnaire effectively. Using the Self-rating Anxiety Scale, Social Support Rating Scale and Subjective Units of Distress scales to analyze anxiety and its risk factors. RESULTS: Under normalized control measures, no staff was infected. The subjective discomfort score was higher in people with lower body mass index (BMI). Young and high social support score were risk factors for anxiety (P < .05), and social support was positively correlated with anxiety. CONCLUSION: The normalization of epidemic is an inevitable trend in a period. A stable and safe medical environment needs to fully eliminate the policy defects, to fit the people and focus on mental health of the people. For patients/family members, who are younger,a lower BMI and higher social support should be attention more.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Procedimentos Cirúrgicos Ambulatórios , SARS-CoV-2 , Ansiedade/prevenção & controle , Ansiedade/epidemiologia , Ansiedade/psicologia , Saúde Mental , Inquéritos e Questionários , China/epidemiologia
13.
Int J Nurs Pract ; : e13203, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37712341

RESUMO

AIMS: This work aims to investigate the association between obesity and risk of delayed discharge and unplanned readmission in day surgery patients. BACKGROUND: Day surgeries are well received and developing rapidly. Associations between obesity and delayed discharge and unplanned readmission, which are clinically relevant outcomes in day surgeries, are complex. DESIGN: A systematic review and meta-analysis was conducted. DATA SOURCES: The PubMed, Web of Science, EMBASE, Cochrane Library, CNKI, VIP, and Wan Fang databases were comprehensively searched from inception until January 2021. REVIEW METHODS: Two independent reviewers assessed the studies and extracted data. Pooled estimates were obtained using a random-effects model. RESULTS: Eleven articles published between 2007 and 2020 were finally included. Obesity appeared not to increase the risk of delayed discharge. However, morbid obesity seemed to be associated with a higher risk of delayed discharge. The meta-analysis revealed no relationship between higher body mass index (BMI) and unplanned readmission for day surgery patients. CONCLUSIONS: Obesity appeared not to increase the risk of delayed discharge except in patients with morbid obesity. Additionally, a higher BMI was not associated with increased risk of unplanned readmission after day surgery. Future studies are required to address this issue further in different types of surgery and areas.

14.
Am J Nephrol ; 53(10): 675-686, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36404708

RESUMO

INTRODUCTION: C3 glomerulopathy (C3G) is a rare, progressive kidney disease resulting from dysregulation of the alternative pathway (AP) of complement. Biomarkers at baseline were investigated in patients with C3G who participated in two phase 2 studies with the factor D (FD) inhibitor, danicopan. METHODS: Patients with biopsy-confirmed C3G, proteinuria ≥500 mg/day, and estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2 were enrolled into two studies (NCT03369236 and NCT03459443). Biomarker analysis was performed for patients with C3G confirmed by central pathology laboratory re-evaluation. Complement and clinical biomarkers, biopsy composite score, and activity and chronicity indices were assessed at baseline and analyzed by pairwise Spearman correlation analysis. RESULTS: Twenty-nine patients were included in the analysis (median [interquartile range] age: 24.0 [10.0] years). Systemic complement AP activation was evident by reduced median concentrations of C3 and C5, elevated sC5b-9, and normal C4, relative to reference ranges. C3 showed strong pairwise correlations with C5 and sC5b-9 (r = 0.80 and -0.73, respectively; p < 0.0001). Baseline Ba and FD concentrations were inversely correlated with eGFR (r = -0.83 and -0.87, respectively; p < 0.0001). Urinary concentrations of sC5b-9 were correlated with both plasma sC5b-9 and proteinuria (r = 0.69 and r = 0.83, respectively; p < 0.0001). Biopsy activity indices correlated strongly with biomarkers of systemic AP activation, including C3 (r = -0.76, p < 0.0001), whereas chronicity indices aligned more closely with eGFR (r = -0.57, p = 0.0021). CONCLUSION: Associations among complement biomarkers, kidney function, and kidney histology may add to the current understanding of C3G and assist with the characterization of patients with this heterogenous disease.


Assuntos
Glomerulonefrite Membranoproliferativa , Nefropatias , Humanos , Adulto Jovem , Adulto , Complemento C3/metabolismo , Fator D do Complemento , Glomerulonefrite Membranoproliferativa/patologia , Biomarcadores , Proteinúria
15.
Thromb J ; 20(1): 36, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761333

RESUMO

BACKGROUND: The anti-coagulation protocol of patients with hemorrhage risk primary disease who need extracorporeal membrane oxygenation (ECMO) supported is controversial. This study evaluated the feasibility of a new anti-coagulation strategy, that is heparin-free after 3000 IU heparin loaded in veno-venous ECMO (VV ECMO) supported acute respiratory failure patients with hemorrhage risk. METHODS: A retrospective study was performed in a series of hemorrhage risk patients supported with VV ECMO at the First Affiliated Hospital of Zhengzhou University, between June 2012 to Sept 2020. A total of 70 patients received a low heparin bolus of 3000 units for cannulation but without subsequent, ongoing heparin administration. Patients were divided into survival (n = 25) and non-survival group (n = 45). Data of coagulation, hemolysis and membrane lung function were calculated and analyzed. The complications of patients were recorded. Finally, the binary Logistic regression was conducted. RESULTS: The longest heparin-free time was 216 h, and the mean heparin-free time was 102 h. Compared with survivors, the non-survivors were showed higher baseline SOFA score and lower platelet counts in 0.5 h, 24 h, 48 h and 96 h after ECMO applied. However, there was no significant differences between survivors and non-survivors in ACT, APTT, INR, D-dimer, fibrinogen, LDH, blood flow rate, Δp and Ppost-MLO2 (all p < 0.05) of all different time point. Moreover, only the baseline SOFA score was significantly associated with mortality (p < 0.001, OR(95%CI): 2.754 (1.486-5.103)) while the baseline levels of ACT, APTT, INR, platelet, D-dimer, fibrinogen and LDH have no association with mortality. The percentage of thrombosis complications was 54.3% (38/70) including 3 oxygenator changed but there was no significant difference of complications in survival and non-survival groups (p > 0.05). CONCLUSIONS: The anticoagulation protocol that no heparin after a 3000 units heparin bolus in VV ECMO supported acute respiratory failure patients with hemorrhage risk is feasible.

16.
Phys Chem Chem Phys ; 24(19): 11536-11543, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35506891

RESUMO

The emerging ferroelectric nematic liquid crystals have been attracting broader interests in new liquid crystal physics and their unique material properties. One big challenge for the ferroelectric nematic research is to enrich the material choice, which is now limited to RM734 and DIO families as representatives, in sharp contrast to the enormously diverse variety of the traditional apolar nematic liquid crystals. Here, we report a design of novel ferroelectric nematic materials with highly fluorinated and rigid mesogens. Noteworthily, they show distinct chemical structural features compared with previous aromatic ester-based molecules. The ferroelectric nematic phase was identified and confirmed through rigorous experiments. The bulk polarization was found to become purely along the long axis director, creating giant dielectric anisotropy. This work demonstrates a great potential for expanding ferroelectric nematic material diversity and will accelerate the corresponding application research and technology innovation.

17.
Int J Nurs Pract ; 28(2): e12951, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33904223

RESUMO

AIM: We aimed to identify the risk factors for delayed discharge in a day surgery centre in west China. BACKGROUND: Delayed discharge affected by various factors is a key indicator for healthcare quality of day surgery. However, few studies have focused on this issue in developing countries where the day surgery started much later. DESIGN: A retrospective case-control design. METHOD: A random sample of 169 delayed discharge cases and 514 normal discharge cases was randomly selected from 38,021 day surgery cases from May 2011 to May 2019 in a tertiary teaching hospital in west China. Socio-demographic and clinical characteristics of patients were collected through the hospital electronic database and a chart review. A multivariate logistic regression was conducted to identify the risk factors for delayed discharge. RESULTS: The urban employee basic medical insurance, comorbidity, general anaesthesia, pain, fever, bleeding and metabolic disorder were identified as the risk factors for delayed discharge. Living in the city where the hospital located was a protective factor for delayed discharge. CONCLUSION: Post-operative complications including fever, pain, bleeding and metabolic disorder were the most important risk factors for delayed discharge. The pre-operative prevention, careful monitoring and rapid reactions to post-operative complications may reduce delayed discharge.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Alta do Paciente , Procedimentos Cirúrgicos Ambulatórios/efeitos adversos , Estudos de Casos e Controles , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco
18.
Angew Chem Int Ed Engl ; 61(28): e202203433, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35478477

RESUMO

The hierarchical self-assembly process opens up great potential for the construction of nanostructural superlattices. Precise regulation of self-assembled superlattices, however, remains a challenge. Even when the primary molecules are precise, the supramolecular motifs (or secondary building blocks) can vary dramatically. In the present work, we propose the concept of unimolecular nanoparticles (UMNPs). The UMNPs act as the supramolecular motif and directly pack into the superlattices. A highly branched giant molecule is presented. We systematically explore its conformations and the superlattice of this giant molecule. Moreover, intriguing complex phases are discovered when blending this UMNP with other conventional giant molecules. These binary mixtures provide direct evidence to support our previously proposed self-sorting process in the self-assembly of "soft alloys". The concept of UMNPs offers a unique approach toward more precise regulation of self-assembled superlattices in soft matter.

19.
Angew Chem Int Ed Engl ; 61(19): e202200637, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35174943

RESUMO

The packing structures of spherical motifs affect the properties of resultant condensed materials such as in metal alloys. Inspired by the classic metallurgy, developing complex alloy-like packing phases in soft matter (also called "soft alloys") is promising for the next-generation superlattice engineering. Nevertheless, the formation of many alloy-like phases in single-component soft matter is usually thermodynamically unfavourable and technically challenging. Here, we utilize a novel self-sorting assembly approach to tackle this challenge in binary blends of soft matter. Two types of giant shape amphiphiles self-sort to form their discrete spherical motifs, which further simultaneously pack into alloy-like phases. Three unconventional spherical packing phases have been observed in these binary systems, including MgZn2 , NaZn13 , and CaCu5 phases. It's the first time that the CaCu5 phase is experimentally observed in soft matter. This work demonstrates a general approach to constructing unconventional spherical packing phases and other complex superlattices in soft matter.

20.
J Am Chem Soc ; 143(42): 17857-17861, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34657433

RESUMO

The emerging ferroelectric nematic (NF) liquid crystal is a novel 3D-ordered liquid exhibiting macroscopic electric polarization. The combination of the ultrahigh dielectric constant, strong nonlinear optical signal, and high sensitivity to the electric field makes NF materials promising for the development of advanced liquid crystal electroopic devices. Previously, all studies focused on the rod-shaped small molecules with limited length (l) range and dipole moment (µ) values. Here, through the precision synthesis, we extend the aromatic rod-shaped mesogen to oligomer/polymer (repeat unit up to 12 with monodisperse molecular-weight dispersion) and increase the µ value over 30 Debye (D). The NF phase has a widespread existence far beyond our expectation and could be observed in all the oligomer/polymer length range. Notably, the NF phase experiences a nontrivial evolution pathway with the traditional apolar nematic phase completely suppressed, i.e., the NF phase nucleates directly from the isotropic liquid phase. The discovery of thte ferroelectric packing of oligomer/polymer rods not only offers the concept of extending the NF state to oligomers/polymers but also provides some previously overlooked insights in oxybenzoate-based liquid crystal polymer materials.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA