Biochar as potential sustainable precursors for activated carbon production: Multiple applications in environmental protection and energy storage

Nowadays, the increasing requirements of portable, implantable, and wearable electronics have greatly stimulated the development of miniaturized energy storage devices (MESDs). Electrochemically active materials and microfabrication techniques are two indispensable parts in MESDs. Particularly, the architecture design of microelectrode arrays is beneficial to the accessibility of two-dimensional (2D) active materials. Therefore, this study reviews the recent advancements in microbatteries and microsupercapacitors based on electrochemically active 2D materials. Emerging microfabrication strategies enable the precise control over the thickness, homogeneity, structure, and dimension in miniaturized devices, which offer tremendous opportunities for achieving both high energy and power densities. Furthermore, smart functions and integrated systems are discussed in detail in light of the emergence of intelligent and interactive modes. Finally, future developments, opportunities, and urgent challenges related to 2D materials, device fabrications, smart responsive designs, and microdevice integrations are provided.

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Two-dimensional materials for miniaturized energy storage devices: from individual devices to smart integrated systems

ConspectusResearch on graphene abounds, from fundamental science to device applications. In pursuit of complementary morphologies, formation of graphene foams is often preferred over the native two-dimensional (2D) forms due to the higher available area. Graphene foams have been successfully prepared by several routes including chemical vapor deposition (CVD) methods and by wet-chemical approaches. For these methods, one often needs either high temperature furnaces and highly pure gases or large amounts of strong acids and oxidants. In 2014, using a commercial laser scribing system as found in most machine shops, a direct lasing of polyimide (PI) plastic films in the air converted the PI into 3D porous graphene, a material termed laser-induced graphene (LIG). This is a one-step method without the need for high-temperature reaction conditions, solvent, or subsequent treatments, and it affords graphene with many five-and seven-membered rings. With such an atomic arrangement, one might call LIG “kinetic grap...

Laser-Induced Graphene

Biomass derived porous carbon for CO2 capture

Recent years have witnessed the rise of graphene and its applications in various electronic devices. Specifically, featuring excellent flexibility, transparency, conductivity, and mechanical robustness, graphene has emerged as a versatile material for flexible electronics. In the past decade, facilitated by various laser processing technologies, including the laser-treatment-induced photoreduction of graphene oxides, flexible patterning, hierarchical structuring, heteroatom doping, controllable thinning, etching, and shock of graphene, along with laser-induced graphene on polyimide, graphene has found broad applications in a wide range of electronic devices, such as power generators, supercapacitors, optoelectronic devices, sensors, and actuators. Here, the recent advancements in the laser fabrication of graphene-based flexible electronic devices are comprehensively summarized. The various laser fabrication technologies that have been employed for the preparation, processing, and modification of graphene and its derivatives are reviewed. A thorough overview of typical laser-enabled flexible electronic devices that are based on various graphene sources is presented. With the rapid progress that has been made in the research on graphene preparation methodologies and laser micronanofabrication technologies, graphene-based electronics may soon undergo fast development.

Laser Fabrication of Graphene-Based Flexible Electronics

The modification of graphene-based materials is an important topic in the field of materials research. This study aims to expand the range of properties for laser-induced graphene (LIG), specifically to tune the hydrophobicity and hydrophilicity of the LIG surfaces. While LIG is normally prepared in the air, here, using selected gas atmospheres, a large change in the water contact angle on the as-prepared LIG surfaces has been observed, from 0° (superhydrophilic) when using O2 or air, to >150° (superhydrophobic) when using Ar or H2. Characterization of the newly derived surfaces shows that the different wetting properties are due to the surface morphology and chemical composition of the LIG. Applications of the superhydrophobic LIG are shown in oil/water separation as well as anti-icing surfaces, while the versatility of the controlled atmosphere chamber fabrication method is demonstrated through the improved microsupercapacitor performance generated from LIG films prepared in an O2 atmosphere.

Laser-Induced Graphene in Controlled Atmospheres: From Superhydrophilic to Superhydrophobic Surfaces.

Biochar as a renewable source for high-performance CO2 sorbent

This study investigated the utility of depression and anxiety symptom screening in patients scheduled for total knee arthroplasty to examine differences in active symptoms according to patients' mental health diagnoses and associated prescription medications.This cross-sectional study analyzed 594 patients scheduled for total knee arthroplasty at a tertiary practice between June 2018 and December 2018. Patients completed Patient-Reported Outcomes Measurements Information System (PROMIS) Depression and Anxiety Computerized Adaptive Tests in clinic quantifying active symptoms. Mental health diagnoses and associated medications were extracted from health records. Statistical analysis assessed between-group differences in mean PROMIS scores and the prevalence of heightened depressive and anxiety symptoms.Multivariable linear regression modeling demonstrated that being diagnosed with depression without medication (β 7.1; P < .001) and with medication (β 8.6; P < .001) were each associated with higher PROMIS Depression scores. Similar modeling demonstrated that patients diagnosed with anxiety and prescribed an anxiolytic (β 8.4; P < .001) were associated with higher PROMIS Anxiety scores than undiagnosed patients. Eighty-six (15%) patients experienced heightened anxiety and/or depressive symptoms. Heightened depressive symptoms were more prevalent among those diagnosed with depression (19% without medication, 24% with antidepressant vs 5% undiagnosed: P < .001). Heightened anxiety symptoms were most prevalent among those diagnosed with anxiety and on anxiolytic medication (25% vs 7% diagnosed with anxiety without medication, 8% undiagnosed: P < .001).One in seven arthroplasty patients screened reported heightened depressive and/or anxiety symptoms. Despite the majority of arthroplasty patients on antidepressants and anxiolytics having symptoms controlled, these patients remain at increased risk of heightened active symptoms. 

Depression and Anxiety Screening Identifies Patients That may Benefit From Treatment Regardless of Existing Diagnoses

Purpose: The objective of this study was to investigate the association between trainee level and surgical time and postoperative complications of anterior cruciate ligament reconstruction (ACLR). Methods: A retrospective chart review of patients who underwent ACLR at an academic orthopaedic ambulatory surgery center collected demographic and clinical information, including the number of trainees present and trainee level. Unadjusted and adjusted regression analyses assessed the association between trainee number and level with surgical time (time from skin incision to closure) and postoperative complications. Results: Of 799 patients in this study operated on by one of five academic sports surgeons, 87% had at least one trainee involved. The average surgical time overall was 93 ± 21 minutes and by trainee level was 99.7 (junior resident), 88.5 (senior residents), 96.6 (fellows), and 95.6 (no trainees). Trainee level was significantly associated with surgical time (P = 0.0008), with increased surgical time in cases involving fellows (0.0011). Fifteen complications (1.9%) were observed within 90 days of surgery. No notable risk factors of postoperative complications were identified. Conclusion: Resident trainee level does not have a notable effect on surgical time or postoperative complications for ACLR at an ambulatory surgery center, although cases involving fellows had longer surgical times. Trainee level was not associated with risk of postoperative complications.

Yash R. Tarkunde

Papers

Laser-Induced Graphene in Controlled Atmospheres: From Superhydrophilic to Superhydrophobic Surfaces.

Biochar as a renewable source for high-performance CO2 sorbent

Depression and Anxiety Screening Identifies Patients That may Benefit From Treatment Regardless of Existing Diagnoses

Effect of Trainee Level on Surgical Time and Postoperative Complications of Anterior Cruciate Ligament Reconstruction