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Porous organic polymers (POPs) constitute an important class of sorbents studied in various adsorption and separation processes. Their unique properties, including high surface areas, adjustable pore sizes, and surface chemistries make them ideal candidates for CO2 capture. To achieve a high CO2 adsorption capacity and selectivity, particularly at the low partition pressures required for post-combustion CO2 capture or direct capture of CO2 from the atmosphere, incorporating amines onto the polymer frameworks or within the pores has shown much promise. This review provides a comprehensive summary of recent studies on the synthesis and CO2 capture performance of amine-functionalized POPs. The review also provides a detailed discussion of structure-performance relationships, focusing on how the loading amount and amine type influence CO2 capture capacity, CO2/N2 selectivity, heat of adsorption, sorption kinetics, and recyclability of POPs. Additionally, the authors offer their perspective on the challenges associated with the practical implementation of amine-modified POPs for CO2 capture.

The challenge of using patient-specific, autologous stem cell therapies in clinical settings is the need for advanced cell processing and expansion technologies. These include decentralized, small-scale manufacturing at the point of care in hospitals. The highest risk for contamination in cell-based therapy products comes from animal- and human-derived components such as serum, blood components, and growth factors. To mitigate the risk of adventitious microorganism contamination, preventive measures like size-exclusion virus removal filtration of cell media components can be employed. This article examines the impact of nanofiltration using nanocellulose-based virus clearance filter paper on the differentiation of human pluripotent stem cells into insulin-producing pancreatic islets (SC-islets). The cells were monitored for biomarkers using flow cytometry and immunohistochemistry along the 7-stage differentiation protocol. The produced SC-islets were evaluated functionally using low and high glucose stimulation under dynamic perifusion conditions. Pluripotent stem cells grown in culture media filtered through 20 nm cut-off nanocellulose filters showed similar expression of desired biomarkers at each stage compared to the control group. At the end of stage 7, SC-islets exhibited a rounded shape and strong expression of insulin, glucagon, and somatostatin in both the control and filtered media groups. The present study demonstrates that SC-islets differentiated with nanofiltered media were functional., Authors in the list of papers of Lulu Wu's thesis: Vasylovska, S., Thorngren, J., Wu, L., Manukyan, L., Mihranyan, A., Lau, J.

We describe a transducer for low-temperature atomic force microscopy based on electromechanical coupling due to a strain-dependent kinetic inductance of a superconducting nanowire. The force sensor is a bending triangular plate (cantilever) whose deflection is measured via a shift in the resonant frequency of a high-Q superconducting microwave resonator at 4.5 GHz. We present design simulations including mechanical finite-element modeling of surface strain and electromagnetic simulations of meandering nanowires with large kinetic inductance. We discuss a lumped-element model of the force sensor and describe the role of an additional shunt inductance for tuning the coupling to the transmission line used to measure the microwave resonance. A detailed description of our fabrication is presented, including information about the process parameters used for each layer. We also discuss the fabrication of sharp tips on the cantilever using focused electron beam-induced deposition of platinum. Finally, we present measurements that characterize the spread of mechanical resonant frequency, the temperature dependence of the microwave resonance, and the sensor’s operation as an electromechanical transducer of force., QC 20240301

In this thesis, we present a force sensor for atomic force microscopy based on cavity optomechanical principles. We explain the function, design, fabrication and characterisation of the force sensor. The mechanical part of the force sensor consists of a cantilever with a very fine tip. Near the cantilever's base is an LC circuit with resonance frequency in the range 4-5 GHz. The inductor consists of a superconducting meandering nanowire that changes its inductance when strained. Thus, the mechanical movement of the cantilever can be detected by measuring how the resonance frequency of the LC circuit changes. The mechanical movement gives rise to sidebands in the microwave spectrum. One detection method is based on the circuit being driven by two microwave tones while the cantilever is actuated near its mechanical resonance by a piezoelectric shaker mounted near the sensor. The amplitude of the measured signal depends on the phase difference between the motion of the cantilever and the microwave tones. Key steps in the fabrication include release of the cantilever by etching away the substrate from both the front and back sides, and deposition of a tip on the free end of the cantilever. Fabrication is done over an entire semiconductor wafer and exhibits high yield. The optomechanical coupling strength g0 was measured in the order of a few Hertz at temperatures of a few millikelvin. However, an accurate calibration of the coupling constant relating mechanical movement of the cantilever to the shift of resonance frequency of the LC circuit was not possible due the presence of a non-thermal fluctuating force. We also present how the microwave losses in the LC circuit vary in the range 1.7-6 K. Our circuits exhibit higher losses than expected from thermal-equilibrium quasiparticles, which we attribute to the circuit dielectric. Quasiparticle losses set an upper limit on the quality factor that our circuits can achieve regardless of topology. In addition, the LC circuit e, Vi presenterar i denna avhandling en kraftsensor för atomkraftsmikroskopi baserad på kavitetsoptomekaniska principer. Vi förklarar kraftsensorns funktion, design, tillverkning och karaktärisering. Kraftsensorns mekaniska del består av en vipparm med en mycket fin spets. Nära vipparmens fästpunkt finns en LC-krets med en resonansfrekvens i mikrovågsområdet 4-5 GHz. Induktansen utgörs av en supraledande slingrande nanotråd som ändrar sin induktans när den töjs. Således kan vipparmens mekaniska rörelse detekteras med en mikrovågssignal som mäter hur LC-kretsens resonansfrekvens förändras. Vipparmens mekaniska rörelse ger upphov till sidoband i mikrovågsspektrat. En detektionsmetod bygger på att kretsen drivs av två mikrovågstoner samtidigt som vipparmen bringas i mekanisk resonans av en piezoelektrisk vibrator monterad nära sensorn. Amplituden på den uppmätta signalen beror på fasskillnaden mellan vipparmens rörelse och mikrovågstonerna. Nyckelstegen i tillverkningen inkluderar deponeringen av spetsen på vipparmen och dess friläggning genom bortetsning av substratet från både fram- och baksidan. Tillverkningen görs över en hel halvledarbricka och uppvisar en hög andel fungerande komponenter. Den optomekaniska kopplingsstyrkan g0 uppmättes i storleksordningen några få Hertz vid temperaturer av några millikelvin. En noggrann kalibrering mellan vipparmens mekaniska rörelse och förskjutningen av LC-kretsens resonansfrekvens försvåras dock av en ännu oidentifierad icketermisk kraft. Vi presenterar även hur mikrovågsförlusterna i LC-kretsen varierar i området 1.7-6 K. Våra kretsar uppvisar större förluster än förväntat vilket vi tillskriver kretsens dielektrikum. Förlusterna från kvasipartiklar sätter en övre gräns för kvalitetsfaktorn som våra kretsar kan uppnå oavsett topologi. LC-kretsen uppvisar samtidigt ett icke-linjärt förhållande mellan ström och kinetisk induktans vilket möjliggör parametrisk förstärkning av de mekaniska sidobanden för att öka känsligheten. Den pres, QC 2024-02-06

We study the response of several microwave resonators made from superconducting NbTiN thin-film meandering nanowires with large kinetic inductance, having different circuit topology and coupling to the transmission line. Reflection measurements reveal the parameters of the circuit and analysis of their temperature dependence in the range 1.7-6 K extract the superconducting energy gap and critical temperature. The lumped-element LC resonator, valid in our frequency range of interest, allows us to predict the quasiparticle contribution to internal loss, independent of circuit topology and characteristic impedance. Our analysis shows that the internal quality factor is limited not by thermal-equilibrium quasiparticles, but an additional temperature-dependent source of internal microwave loss., QC 20240702

Electromechanical transduction gain of 21 dB is realized in a micro-cantilever resonant force sensor operated in the unresolved-sideband regime. Strain-dependent kinetic inductance weakly couples cantilever motion to a superconducting nonlinear resonant circuit. A single pump generates motional sidebands and parametrically amplifies them via four-wave mixing. We study the gain and added noise, and we analyze potential benefits of this integrated amplification process in the context force sensitivity., QC 20240702

The correlation between lignin structure, its properties, and performance is crucial for lignin engineering in high-value products. Currently, a widespread approach is to compare lignins which differ by more than one parameter (i.e., Kraft vs organosolv vs lignosulfonates) in various applications by attributing the changes in their properties/performance specifically to a certain variable (i.e., phenolic −OH groups). Herein, we suggest a novel approach to overcome this issue by changing only one variable at a time while keeping all others constant before investigating the lignin properties/performance. Indulin AT (Ind-AT), a softwood Kraft lignin, was chosen as the model substrate for this study. Selective (analytical) lignin modifications were used to mask/convert specific functionalities, such as aliphatic (AliphOH) including benzylic −OH (BenzOH) and phenolic −OH (PhOH) groups, carboxyl groups (−COOH) and carbonyl groups (CO) via methylation, acetylation, and reduction. The selectivity and completeness of the reactions were verified by comprehensive NMR analysis (31P and 2D HSQC) of the modified preparations together with state-of-the-art molar mass (MM) characterization. Methylene blue (MB) adsorption, antioxidant activity, and glass transition temperature (Tg) were used to demonstrate and compare the properties/performance of the obtained modified lignins. We found that the contribution of different functionalities in the adsorption of MB follows the trend BenzOH > −COOH > AlipOH > PhOH. Noteworthy, benzylic −OH contributes ca. 3 and 2.3 times more than phenolic and aliphatic −OH, respectively. An 11% and 17% increase of Tg was observed with respect to the unmodified Indulin by methylating benzylic −OH groups and through reduction, respectively, while full acetylation/methylation of aliphatic and phenolic −OH groups resulted in lower Tg. nRSI experiments revealed that phenolic −OH play a crucial role in increasing the antioxidant activity of lignin, wh

Selective copper recovery from copper tailings reduces environmental pollution caused by mining activities and provides a valuable source of copper. Furthermore, polymer waste accumulation and handling small functional materials like resins remains challenging. In this study, a 3D-printed adsorbent for selective copper recovery from copper tailings was designed by functionalizing recycled polymer with a chelating resin and 3D-printing using selective laser sintering technique. The 3D-printed adsorbent was characterized, and its adsorption performance examined under varying conditions. The adsorption kinetics and adsorption isotherm fitted well to the pseudo-second-order kinetics and Langmuir isotherm models, suggesting chemical and monolayer adsorption processes. FTIR indicated coordination as the possible adsorption mechanism. Thermodynamics revealed an endothermic process. The 3D-printed adsorbent demonstrated an excellent Cu(II) adsorption, high selectivity towards Cu(II), and reusability. This work offers a promising 3D-printed adsorbent for selective Cu(II) recovery, while also addressing polymer waste and particle handling issues.

In recent decades, photoluminescence properties of single molecules and ions have opened new possibilities for studies on smaller size scales, below the light-diffraction limit. In this thesis, the advantages of such single photon emitters were harnessed and studied mainly in the field of biophysics, but also, in investigations within solid state photonics. The first aspect encompassed studies on extracellular vesicles (EVs) and nanovesicles derived from red blood cell (RBC) membranes which were bioengineered for drug delivery applications. RBC-derived vesicles demonstrated high biocompatibility and low immunogenicity, offering superior production scalability over physiological EVs. However, thorough physical characterizations of such nanovesicles are yet to be developed. Such investigations are essential for their clinical deployment, for therapeutic and diagnostic purposes. Initially, the morphology and size-stability of vesicles were investigated by applying atomic force microscopy and dynamic light scattering. These studies demonstrated the size heterogeneity and agglomeration tendencies of the vesicles. Comparative studies on physiological EVs revealed a higher size stability, while RBC-produced vesicles showed about 50 % reversible agglomerations. Secondly, a dual-colour coincident fluorescent burst (DC-CFB) experimental analysis technique was developed. DC-CFB was then used to characterize and profile the cargo-loading yields of bioengineered nanovesicles, overcoming challenges related to their small size (below the diffraction limit), their inherent heterogeneity, and the presence of free, non-encapsulated cargoes. The developed methodology was then applied to explore the loading with relatively small single nucleotides (dUTP) as well as larger antibody (Ab) molecules, motivated by the prospective role of such EVs and EV-mimetic bioengineered vesicles as nanocarriers of therapeutic drugs. The studies demonstrated consistent average loading yields of around 1, Under de senaste årtiondena har fotoluminescens-egenskaper hos enskilda molekyler och joner öppnat nya möjligheter till studier på mindre storleksskalor, under ljusdiffraktionsgränsen. I den här avhandlingen utnyttjades och studerades fördelarna med sådana enskilda foton-källor främst inom biofysik, men också för undersökningar inom fasta tillståndets fotonik. Det första aspekten omfattade studier av extracellulära vesiklar (EVs) och nanovesiklar, genererade från röda blodkroppars (RBC) membran, och utformade för applikationer rörande leverans av läkemedel i kroppen. De RBC-genererade vesiklarna uppvisade hög biokompatibilitet och låg immunogenicitet och erbjöd en överlägsen uppskalbarhet för produktion jämfört med fysiologiska EVs. Emellertid måste noggranna fysiska karakteriseringar av sådana nanovesiklar ännu utvecklas. Sådana undersökningar är nödvändiga för att i förlängningen kunna använda denna typ av vesiklar klinikst, för terapeutiska och diagnostiska ändamål. Inledningsvis undersöktes morfologin och storleksstabiliteten hos vesiklarna genom atomkraftsmikroskopi och dynamisk ljusspridning. Dessa studier visade på storleksheterogenitet och agglomereringstendenser hos vesiklarna. Jämförande studier av fysiologiska EVs avslöjade deras förhållandevis högre storleksstabilitet, medan RBC-producerade vesiklar uppvisade reversibla agglomerationer i omkring 50 % av fallen. För det andra utvecklades en experimentell analysmetod med tvåfärgs-avläsning av sammanfallande fluorescens-signaler (DC-CFB). Metoden användes sedan för att karakterisera och profilera molekylupptaget hos de bioteknologiskt framtagna nanovesiklarna. Därmed var det möjligt att hantera vesiklarnas ringa storlek (under diffraktionsgränsen), deras inneboende heterogenitet och närvaron av fria, icke-inkapslade molekyler. Den utvecklade metoden tillämpades därefter för att utforska upptaget i vesiklarna av relativt små nukleotider (dUTP) såväl som av större antikroppsmolekyl (Ab), motiverat utifrån en, QC 2024-01-08

In healthy individuals, the intestinal epithelium forms a tight barrier to prevent gut bacteria from reaching blood circulation. To study the effect of probiotics, dietary compounds and drugs on gut barrier formation and disruption, human gut epithelial and bacterial cells can be cocultured in an in vitro model called the human microbial crosstalk (HuMiX) gut-on-a-chip system. Here, we present the design, fabrication and integration of thin-film electrodes into the HuMiX platform to measure transepithelial electrical resistance (TEER) as a direct readout on barrier tightness in real-time. As various aspects of the HuMiX platform have already been set in their design, such as multiple compressible layers, uneven surfaces and nontransparent materials, a novel fabrication method was developed whereby thin-film metal electrodes were first deposited on flexible substrates and sequentially integrated with the HuMiX system via a transfer-tape approach. Moreover, to measure localized TEER along the cell culture chamber, we integrated multiple electrodes that were connected to an impedance analyzer via a multiplexer. We further developed a dynamic normalization method because the active measurement area depends on the measured TEER levels. The fabrication process and system setup can be applicable to other barrier-on-chip systems. As a proof-of-concept, we measured the barrier formation of a cancerous Caco-2 cell line in real-time, which was mapped at four spatially separated positions along the HuMiX culture area.

Additive Manufacturing (AM), over the past decade, has evolved into a versatile technology with significant applications in pharmaceutical research. This technology enables the production of drug formulations tailored to individual patients, offering customization in both dosage and dissolution profiles. While challenges in mass production persist, 3D printing, particularly through techniques like Fused Deposition Modeling (FDM) and Semi Solid Extrusion (SSE), proves ideal for crafting smaller batches of personalized dosage forms. A prevalent issue in drug development revolves around poor water solubility, impacting bioavailability upon oral administration. To combat this, the integration of mesoporous materials emerges as a promising strategy to enhance the dissolution of poorly water-soluble drugs. Here, the applicability of mesoporous materials is explored, as well as their incorporation with various AM techniques. Overall, the thesis dives into the investigation of combinatorial formulations, incorporating at least one 3D printed component to address specific requirements in drug delivery. By combining FDM with Selective Laser Sintering (SLS), a hybrid two-compartmental formulation is developed. The durable FDM-printed shell regulates buffer medium access to the contained SLS-produced inserts loaded with the drug. Varying printing parameters and insert combinations within the shell showcase the adjustability and flexibility of this hybrid approach. Tablets with different infill percentages, containing drug-loaded mesoporous materials, are developed. Poorly water-soluble drugs are successfully amorphized within mesoporous material pores, formulated into filaments through Hot Melt Extrusion (HME), and printed via FDM. These tablets exhibit improved dissolution compared to the crystalline drug, with the dissolution behavior regulated also by the infill percentage. The study explores the impact of drug-loaded mesoporous materials on HME-produced filament properties

Antibiotic resistance is becoming an increasing concern, necessitating new ways to diagnose and treat it rapidly and accurately. One proposed solution is the use of nucleic acid amplification tests, capable of detecting resistance in just a few hours, as opposed to the several days that traditional testing methods may require. One concept for such a test involves the volume-amplified magnetic nanobead detection assay (VAM-NDA), which combines rolling circle amplification (RCA), an isothermal amplification method, with magnetic nanoparticles (MNPs) for the detection of the RCA products. In this thesis, improvements have been made to the VAM-NDA. Coupling of RCA products with microparticles allowed a greater hydrodynamic increase of the MNPs when bound to these products, facilitating the detection of shorter products. Moreover, circle-to-circle amplification (C2CA) was performed, a technique comprising two RCA reactions, increasing the sensitivity of the assay and leading to a 1 attomole limit of detection. Optimization of several reaction parameters has allowed for increased sensitivity. Of highest relevance are the changes made to the length of padlock probes, oligonucleotides used for target recognition. These changes resulted in faster amplification. Equally important is the work conducted on phi29 DNA polymerase. Different manufacturers and mutants of this enzyme were tested, resulting in an improved and faster amplification. However, a previously undiscovered feature of this enzyme was also investigated, where phi29 amplification is competitively inhibited by the presence of ssDNA oligonucleotides, regardless of whether digestion of those is possible or not. Finally, a novel detection method for RCA products was developed, where nanoparticles were made to aggregate with the DNA products, resulting in aggregates visible to the naked eye. This method was further optimized, and integrated with C2CA, as well as substituting MNPs for coloured polystyrene nanoparticl, Defense avaliable online via link: https://uu-se.zoom.us/j/3194015814?omn=61419802403 or meeting ID 319 401 5814. Passcode 1608

We report the one-pot synthesis of a chabazite (CHA)/erionite (ERI)-type zeolite intergrowth structure characterized by adjustable extents of intergrowth enrichment and Si/Al molar ratios. This method utilizes readily synthesizable 6-azaspiro[5.6]dodecan-6-ium as the exclusive organic structure-directing agent (OSDA) within a potassium-dominant environment. High-throughput simulations were used to accurately determine the templating energy and molecular shape, facilitating the selection of an optimally biselective OSDA from among thousands of prospective candidates. The coexistence of the crystal phases, forming a distinct structure comprising disk-like CHA regions bridged by ERI-rich pillars, was corroborated via rigorous powder X-ray diffraction and integrated differential-phase contrast scanning transmission electron microscopy (iDPC S/TEM) analyses. iDPC S/TEM imaging further revealed the presence of single offretite layers dispersed within the ERI phase. The ratio of crystal phases between CHA and ERI in this type of intergrowth could be varied systematically by changing both the OSDA/Si and K/Si ratios. Two intergrown zeolite samples with different Si/Al molar ratios were tested for the selective catalytic reduction (SCR) of NOx with NH3, showing competitive catalytic performance and hydrothermal stability compared to that of the industry-standard commercial NH3-SCR catalyst, Cu-SSZ-13, prevalent in automotive applications. Collectively, this work underscores the potential of our approach for the synthesis and optimization of adjustable intergrown zeolite structures, offering competitive alternatives for key industrial processes.

Particle sintering and reshaping constitute the main cause for catalyst deactivation. An atomic-scale understanding of the correlation among the catalyst structure, its support, and the gas phase under realistic reaction conditions is required for its suppression. In this study, we combined high-energy grazing incidence X-ray diffraction, in situ mass spectrometry, ex situ scanning electron microscopy, and density functional theory calculations to unravel the driving force behind the composition-dependent particle shape changes and sintering processes of alpha-Al2O3(0001)-supported Pt-Pd alloy nanoparticles under realistic reaction conditions for CO oxidation. We find that pure Pt and Pt-rich particles, initially kinetically trapped in metastable flat particle shapes, undergo a strong reaction-induced height increase to adopt a more stable, theoretically predicted compact equilibrium shape. Contrarily, Pd-rich particles prove to be more resistant against shape changes, since they exhibit already a shape close to equilibrium. We thus conclude that the observed initial deviations in particle shape from the theoretical predictions are due to kinetic limitations during growth. Our data provide information on the segregation state of the alloy particles, indicating a Pt core and Pd shell structure under strongly reducing conditions and the alloying of Pt and Pd under the reaction conditions for CO oxidation close to stoichiometry.

The ability to manipulate magnetic anisotropy is essential for magnetic sensing and storage tools. Surface carbon species offer cost-effective alternatives to metal-oxide and noble metal capping layers, inducing perpendicular magnetic anisotropy in ultrathin ferromagnetic films. Here, the different mechanisms by which the magnetism in a few-layer-thick Co thin film is modified upon adsorption of carbon monoxide (CO), dispersed carbon, and graphene are elucidated. Using X-ray microscopy with chemical and magnetic sensitivity, the in-plane to out-of-plane spin reorientation transition in cobalt is monitored during the accumulation of surface carbon up to the formation of graphene. Complementary magneto-optical measurements show weak perpendicular magnetic anisotropy (PMA) at room temperature for dispersed carbon on Co, while graphene-covered cobalt exhibits a significant out-of-plane coercive field. Density-functional theory (DFT) calculations show that going from CO/Co to C/Co and to graphene/Co, the magnetocrystalline and magnetostatic anisotropies combined promote out-of-plane magnetization. Anisotropy energies weakly depend on carbidic species coverage. Instead, the evolution of the carbon chemical state from carbidic to graphitic is accompanied by an exponential increase in the characteristic domain size, controlled by the magnetic anisotropy energy. Beyond providing a basic understanding of the carbon-ferromagnet interfaces, this study presents a sustainable approach to tailor magnetic anisotropy in ultrathin ferromagnetic films. Magnetic properties of Co ultrathin films are shown to undergo dramatic changes upon surface carbon accumulation. Chemical transformation from molecular carbon monoxide to surface carbide and to a graphene layer progressively enhances the perpendicular magnetic anisotropy of Co. Calculations reveal that magnetocrystalline and magnetostatic contributions play distinctly different roles for the different carbon species.image

The solid-state field-effect transistor, FET, and its theories were paramount in the discovery and studies of graphene. In the past two decades another transistor based on conducting polymers, called organic electrochemical transistor (ECT), has been developed and largely studied. The main difference between organic ECTs and FETs is the mode and extent of channel doping; while in FETs the channel only has surface doping through dipoles, the mixed ionic-electronic conductivity of the channel material in organic ECTs enables bulk electrochemical doping. As a result, organic ECTs maximize conductance modulation at the expense of speed. To date ECTs have been based on conducting polymers, but here we show that MXenes, a class of 2D materials beyond graphene, enable the realization of electrochemical transistors (ECTs). We show that the formulas for organic ECTs can be applied to these 2D ECTs and used to extract parameters like mobility. These MXene ECTs have high transconductance values but low on-off ratios. We further show that conductance switching data measured using ECT, in combination with other in situ-ex situ electrochemical measurements, is a powerful tool for correlating the change in conductance to that of the redox state, to our knowledge, this is the first report of this important correlation for MXene films. 2D ECTs can draw great inspiration and theoretical tools from the field of organic ECTs and have the potential to considerably extend the capabilities of transistors beyond those of conducting polymer ECTs, with added properties such as extreme heat resistance, tolerance for solvents, and higher conductivity for both electrons and ions than conducting polymers. Here we show that not only conducting polymers, but also 2D MXenes can be used as materials for electrochemical transistors ECTs. MXene extend the capabilities of ECTs with properties such as extreme heat resistance, and higher conductivity/speeds.

Metal-organic frameworks (MOFs) are a rapidly growing class of materials that offer great promise in various applications. However, the synthesis remains challenging: for example, a range of crystal structures can often be accessed from the same building blocks, which complicates the phase selectivity. Likewise, the high sensitivity to slight changes in synthesis conditions may cause reproducibility issues. This is crucial, as it hampers the research and commercialization of affected MOFs. Here, it presents the first-ever interlaboratory study of the synthetic reproducibility of two Zr-porphyrin MOFs, PCN-222 and PCN-224, to investigate the scope of this problem. For PCN-222, only one sample out of ten was phase pure and of the correct symmetry, while for PCN-224, three are phase pure, although none of these show the spatial linker order characteristic of PCN-224. Instead, these samples resemble dPCN-224 (disordered PCN-224), which has recently been reported. The variability in thermal behavior, defect content, and surface area of the synthesised samples are also studied. The results have important ramifications for field of metal-organic frameworks and their crystallization, by highlighting the synthetic challenges associated with a multi-variable synthesis space and flat energy landscapes characteristic of MOFs. It performed an interlaboratory study of the synthesis of the metal-organic frameworks (MOFs) PCN-222 and PCN-224. Ten participants independently synthesized the two MOFs and the products are analyzed, primarily by X-ray diffraction. The success rates are low (one-three samples corresponding to a pure sample of the correct phase), thus highlighting the problems with irreproducibility in MOF synthesis. image

Industrial and mining wastewater, along with copper tailings, are typically highly acidic and contain copper and other heavy metals, which may contaminate and damage the environment. Copper (Cu) is, however, a valuable metal, making its removal and recovery from such wastewater and tailings environmentally and economically advantageous. Chelating ion exchange resins featuring bis-picolylamine functional groups are especially suitable for application requiring selective recovery of Cu(II) from highly acidic media. In this study, and for the first time, the kinetics, binding capacity and selectivity of Lewatit MDS TP 220 chelating resin towards Cu(II) are reported. The resin was characterized by Zeta potential, scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Factors including pH, initial concentration, contact time, temperature, and selectivity were investigated to assess the adsorption performance of the chelating resin. The adsorption kinetics tests revealed fast adsorption within the first 5–30 min and fitted the pseudo-second-order model, signifying chemisorption process. The adsorption isotherm followed the Langmuir model, implying monolayer adsorption process. The maximum adsorption capacity (qm) for Cu(II) determined by the Langmuir model was 103.9 mg/g. The adsorption thermodynamics showed an endothermic and spontaneous adsorption. FTIR and XPS studies suggested coordination or chelation as the possible adsorption mechanism. Lewatit MDS TP 220 exhibited excellent Cu(II) adsorption, desorption with 2 M ammonium hydroxide (NH4OH), and selectivity in multi-metal ions solution. Additionally, the resin demonstrated excellent reusability after five regeneration steps. This chelating resin is a potential adsorbent for effective and recurrent recovery of Cu(II) from copper tailings and wastewater, thereby contributing to environmental remediation.

Synthetic single-stranded oligonucleotides play crucial roles in DNA amplification reactions for various applications, such as serving as primers, enabling magnetic separation, and generating dsDNA for subsequent digestion. Typically, these oligos are added in excess to ensure rapid binding to their intended targets. However, while performing rolling circle amplification (RCA) using phi29 DNA polymerase, we observed a decrease in amplification efficiency when oligos were present in the reaction. This phenomenon was consistently observed in two separate laboratories, prompting this study to delve into the root causes responsible for the decline in RCA efficiency. The lowered efficiency was consistent regardless of the manufacturer or any mutations in the phi29 polymerase. We identified several variables that influenced RCA efficiency, mainly the length of the oligos used and the presence of modifications, particularly those obstructing 3’ end digestion. This strongly suggests that the exonuclease domain of phi29 DNA polymerase is responsible for the competition-based inhibition. Our investigation shows that even picomole quantities of oligos can significantly reduce total DNA production during the phi29 DNA polymerase-mediated amplification process. Conversely, the addition of oligos to the reaction did not impede the efficiency of Bst 3.0 polymerase, likely due to the lack of an exonuclease domain of said polymerase. While increasing the quantity of phi29 DNA polymerase in the reaction partially alleviated the adverse effects of excess oligos, we believe it is crucial to carefully optimize the oligo quantities to achieve maximum amplification of the desired targets.

Selective Laser Sintering (SLS) has the potential to offer a more accurate alternative to current-practice manipulation of oral dosage forms for pediatric, geriatric, and dysphagia-suffering patient groups. In order to create the best possible dosage forms for these patient groups, an in-depth look into how a dosage forms geometry impacts the overall properties is essential. In this study, the impact of geometry on SLS manufactured oral dosage forms on the tablet’s microstructure, actual-to-theoretical volume, mass deviation, disintegration, and dissolution was investigated. Three different shapes; cylinder, hollow cylinder, and conical frustum with similar surface area (SA), as well as three cylinders with different diameters, were investigated. The results indicate that the geometry has an impact on the mass uniformity, resultant volume, disintegration, and dissolution properties of the tablets. The mass uniformity analysis of the tablets provided the most variation between tablets of different sizes, with more uniformity for tablets with similar SA-to-volume ratio (SA/V). When examining the actual-to-theoretical volume of the tablets, a greater variance between the actual and theoretical volumes for shapes with higher overall SA was observed. The values found are approximately 1.05 for the three differently sized cylinders, 1.23 for the conical frustum, and 1.44 for the hollow cylinder, following this trend. Disintegration data supported a link between SA/V and average disintegration time, observed with the tablet of the highest SA/V disintegrating in 12 s and the tablet with the lowest SA/V disintegrating in 58 s. Dissolution results also indicated a strong dependence on SA/V. Hence, when novel ways to produce oral dosage form tablets become available by additive manufacturing, such as SLS, both geometry and SA/V must be taken into consideration in the tablet design process to ensure appropriate release kinetics and dosing standards.

Per- and polyfluoroalkyl substances (PFAS) are very stable and ubiquitously distributed in terrestrial and aquatic environments, and treatment and remediation techniques for the removal of PFAS are urgently needed. In this study, mesoporous silica matrix SBA-15 grafted with alkyl amino groups was used to remove perfluorooctanoate (PFOA) from aqueous solutions. The amino groups were grafted onto SBA-15 by the condensation of alkyl amino silanes. The synthesized adsorbents were studied by SEM, TEM, IR, low-temperature nitrogen sorption, and XRD. The solid-state and liquid 19F NMR spectroscopy, EDX, and LC-MS/MS results showed high adsorption efficiency and rapid reaction kinetics. In freshly prepared solutions and on the surface of the sorbents, the presence of PFOA micelles was observed. Furthermore, the introduction of amine-containing groups into the structure of the sorbent allows the sorption of up to 649 mg/g of PFOA from solutions. Results showed that the protonated surface amino groups and PFOA interacted electrostatically. The obtained results open perspectives for producing adsorbents for facile extraction of PFAS.

A Cryptocurrency known as Bitcoin (BTC) is intended to function as money and a mode of payment independent of any one individual, organisation, or body. This eliminates the requirement for financial transactions to involve a reliable third party (like a bank or mint). It can be acquired on a number of exchanges and is given to blockchain miners as compensation for validating transactions. A cryptocurrency is a digital medium of exchange similar to the US dollar that controls the creation of new monetary units and verifies the transfer of funds using cryptographic techniques and protocol. Bitcoin and Cryptocurrency provide a comprehensive introduction to the revolutionary yet often misunderstood new technologies of digital currency. Whether you are a student, software developer, tech entrepreneur, or researcher in computer science, this authoritative and self-contained book tells you everything you need to know about the new global money for the Internet age. Following chapters are included in this book: 1. Bitcoin2. Bitcoin Digital Currency: Advantages & Disadvantages3. Decrypting Crypto Tax4. Cryptocurrency, Bitcoin, And the Future- A Conceptual Study5. Decrypting Dangers: Exploring the Nexus Between Cryptocurrency and Financial Crime6. Bitcoin: Economics, Technology, and Governance7. Online Payment Opportunities: PayPal and Bitcoin8. Power, Property, and Freedom: Bitcoin Discourse9. Cryptocurrency and Banking: Challenges, Considerations, and Disruptions - A Study 10. Cryptocurrency and its impact on the Banking Industry11. Advancing Technologies in Commerce for Sustainable Practices12. Cryptocurrency and Financial Markets

By measuring the concentration of gases such as ammonia (NH3) and hydrogen sulfide (H2S) in paddy field water, rice farmers can more precisely control fertilization levels and monitor over-all water quality. To this end, the SOMIRO (Soft Milli-Robots) project aims to deliver the world’s first energy-autonomous swimming soft milli-robot equipped with gas sensing technology for use in precision agriculture. Gas sensors based on metal oxide semiconductor (MOS) nanostructures can satisfy the constraints on size, power consumption and gas sensitivity. However, the sensing performance of nano-MOS sensors is severely inhibited by humidity, making inwater gas sensing particularly challenging. A solution is proposed in this work through coating nano-MOS gas sensors with a hydrophobic, gas permeable film of PDMS. Two approaches to PDMS coating were explored: drop-casting with a micropipette and spray-coating with an airbrush. By spray-coating, micrometer thick PDMS films were prepared on the surfaces of Ag and Pt doped SnO2 (Ag+Pt/SnO2) gas sensors and the sensor response to NH3 in air and inwater was measured at 35 °C and in room temperature, respectively. The PDMS coatedAg+Pt/SnO2 sensors were sensitive to NH3 dissolved in water at concentrations as low as 5 ppm, confirming the validity of the proposed approach. This work constitutes the first reported successful use of PDMS coated nano-MOS gas sensors for in-water gas sensing.