Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
373
result(s) for
"DuPont, Robert L"
Sort by:
Staggered circular nanoporous graphene converts electromagnetic waves into electricity
Harvesting largely ignored and wasted electromagnetic (EM) energy released by electronic devices and converting it into direct current (DC) electricity is an attractive strategy not only to reduce EM pollution but also address the ever-increasing energy crisis. Here we report the synthesis of nanoparticle-templated graphene with monodisperse and staggered circular nanopores enabling an EM–heat–DC conversion pathway. We experimentally and theoretically demonstrate that this staggered nanoporous structure alters graphene’s electronic and phononic properties by synergistically manipulating its intralayer nanostructures and interlayer interactions. The staggered circular nanoporous graphene exhibits an anomalous combination of properties, which lead to an efficient absorption and conversion of EM waves into heat and in turn an output of DC electricity through the thermoelectric effect. Overall, our results advance the fundamental understanding of the structure–property relationships of ordered nanoporous graphene, providing an effective strategy to reduce EM pollution and generate electric energy.
The electromagnetic (EM) energy released by electronic devices in the environment is largely wasted and contributes to EM pollution. Here, the authors report the synthesis of staggered circular nanoporous graphene enabling the absorption and conversion of EM waves into electricity via the thermoelectric effect.
Journal Article
Functional nanoporous graphene superlattice
Two-dimensional (2D) superlattices, formed by stacking sublattices of 2D materials, have emerged as a powerful platform for tailoring and enhancing material properties beyond their intrinsic characteristics. However, conventional synthesis methods are limited to pristine 2D material sublattices, posing a significant practical challenge when it comes to stacking chemically modified sublattices. Here we report a chemical synthesis method that overcomes this challenge by creating a unique 2D graphene superlattice, stacking graphene sublattices with monodisperse, nanometer-sized, square-shaped pores and strategically doped elements at the pore edges. The resulting graphene superlattice exhibits remarkable correlations between quantum phases at both the electron and phonon levels, leading to diverse functionalities, such as electromagnetic shielding, energy harvesting, optoelectronics, and thermoelectrics. Overall, our findings not only provide chemical design principles for synthesizing and understanding functional 2D superlattices but also expand their enhanced functionality and extensive application potential compared to their pristine counterparts.
Here, the authors report the synthesis and characterization of doped nanoporous graphene superlattices, showing their improved properties for electromagnetic shielding, energy harvesting, optoelectronic and thermoelectric applications.
Journal Article
Polysubstance use in the U.S. opioid crisis
Interventions to address the U.S. opioid crisis primarily target opioid use, misuse, and addiction, but because the opioid crisis includes multiple substances, the opioid specificity of interventions may limit their ability to address the broader problem of polysubstance use. Overlap of opioids with other substances ranges from shifts among the substances used across the lifespan to simultaneous co-use of substances that span similar and disparate pharmacological categories. Evidence suggests that nonmedical opioid users quite commonly use other drugs, and this polysubstance use contributes to increasing morbidity and mortality. Reasons for adding other substances to opioids include enhancement of the high (additive or synergistic reward), compensation for undesired effects of one drug by taking another, compensation for negative internal states, or a common predisposition that is related to all substance consumption. But consumption of multiple substances may itself have unique effects. To achieve the maximum benefit, addressing the overlap of opioids with multiple other substances is needed across the spectrum of prevention and treatment interventions, overdose reversal, public health surveillance, and research. By addressing the multiple patterns of consumption and the reasons that people mix opioids with other substances, interventions and research may be enhanced.
Journal Article
Five year outcomes in a cohort study of physicians treated for substance use disorders in the United States
Objective To evaluate the effectiveness of US state physician health programmes in treating physicians with substance use disorders.Design Five year, longitudinal, cohort study.Setting Purposive sample of 16 state physician health programmes in the United States.Participants 904 physicians consecutively admitted to one of the 16 programmes from September 1995 to September 2001.Main outcome measures Completion of the programme, continued alcohol and drug misuse (regular urine tests), and occupational status at five years.Results 155 of 802 physicians (19.3%) with known outcomes failed the programme, usually early during treatment. Of the 647 (80.7%) who completed treatment and resumed practice under supervision and monitoring, alcohol or drug misuse was detected by urine testing in 126 (19%) over five years; 33 (26%) of these had a repeat positive test result. At five year follow-up, 631 (78.7%) physicians were licensed and working, 87 (10.8%) had their licences revoked, 28 (3.5%) had retired, 30 (3.7%) had died, and 26 (3.2%) had unknown status.Conclusion About three quarters of US physicians with substance use disorders managed in this subset of physician health programmes had favourable outcomes at five years. Such programmes seem to provide an appropriate combination of treatment, support, and sanctions to manage addiction among physicians effectively.
Journal Article
Magnetocontrollable droplet mobility on liquid crystal-infused porous surfaces
Magnetocontrollable droplet mobility on surfaces of both solids and simple fluids have been widely used in a wide range of applications. However, little is understood about the effect of the magnetic field on the wettability and mobility of droplets on structured fluids. Here, we report the manipulation of the dynamic behaviors of water droplets on a film of thermotropic liquid crystals (LCs). We find that the static wetting behavior and static friction of water droplets on a 4′-octyl-4-biphenylcarbonitrile (8CB) film strongly depend on the LC mesophases, and that a magnetic field caused no measurable change to these properties. However, we find that the droplet dynamics can be affected by a magnetic field as it slides on a nematic 8CB film, but not on isotropic 8CB, and is dependent on both the direction and strength of the magnetic field. By measuring the dynamic friction of a droplet sliding on a nematic 8CB film, we find that a magnetic field alters the internal orientational ordering of the 8CB which in turn affects its viscosity. We support this interpretation with a scaling argument using the LC magnetic coherence length that includes (i) the elastic energy from the long-range orientational ordering of 8CB and (ii) the free energy from the interaction between 8CB and a magnetic field. Overall, these results advance our understanding of droplet mobility on LC films and enable new designs for responsive surfaces that can manipulate the mobility of water droplets.
Journal Article
Opioid Use Disorder in Physicians
To the Editor:
In the Perspective article by Beletsky and colleagues (Aug. 29 issue),
1
the authors overlook the fact that physicians with opioid use disorder who were receiving care in physician health programs (PHPs) had the same remarkably positive long-term outcomes as their peers with other types of substance use disorders.
2
Only one physician received methadone, which was used to treat chronic pain. None received opioid agonists to treat their opioid use disorder. All were randomly tested for alcohol, opioid, and other drug use during the 5 years of their care. Only 22% had any positive test over that long . . .
Journal Article
Medicinal Use of Marijuana
Currently, 18 states allow the medicinal use of marijuana, but it remains controversial among physicians. This Clinical Decisions presents both sides of the heated debate. Vote and share your comments at NEJM.org.
Marilyn is a 68-year-old woman with breast cancer metastatic to the lungs and the thoracic and lumbar spine. She is currently undergoing chemotherapy with doxorubicin. She reports having very low energy, minimal appetite, and substantial pain in her thoracic and lumbar spine. For relief of nausea, she has taken ondansetron and prochlorperazine, with minimal success. She has been taking 1000 mg of acetaminophen every 8 hours for the pain. Sometimes at night she takes 5 mg or 10 mg of oxycodone to help provide pain relief. During a visit with her primary care physician she asks about the possibility . . .
Journal Article