Chain Units Research Articles

Nonhalogenated Solvent-Processed Efficient Ternary All-Polymer Solar Cells Enabled by the Introduction of a Naphthyloxy Group into the Side Chain of Polymer Donors.

Conjugated polymer donors are crucial for enhancing the power conversion efficiencies (PCEs) in all-polymer solar cells (All-PSCs) in nonhalogenated solvents. In this work, three wide-band-gap polymer donors (Sil-D1, Ph-Sil-D1, and Nap-Sil-D1) based on dithienobenzothiadiazole (DTBT) and benzodithiophene (BDT) donor moieties optimized by side chain engineering were designed and synthesized. Alkyl (Sil-D1), phenyloxy (Ph-Sil-D1), and naphthyloxy (Nap-Sil-D1) alkyl siloxane side chain units were incorporated into these polymer donors, respectively. Notably, the Nap-Sil-D1 polymer donor had a greater conjugation length, π-electron delocalization, and improved dipole moment. The deepest highest occupied molecular orbital level of Nap-Sil-D1, with a high absorption coefficient, showed better aggregation properties. In addition, reduced bimolecular recombination and trap-state density generated a high charge transfer to cause a significant enhancement of open-circuit voltage, current density, and fill factor values of 0.94 V, 25.5 mA/cm2, and 70.4%, respectively, for the Nap-Sil-D1-blended All-PSC ternary device (PM6:Nap-Sil-D1:PY-IT), with the highest PCE of 16.8% in the o-xylene solvent, compared to other polymers (Sil-D1 and Ph-Sil-D1) with PCEs of 15.5 and 16.2%. As a result, this optimized device architecture was found to be the most promising as a nonhalogenated solvent processed in additive-free ternary All-PSCs with good stability.

Spectro-spatial analysis of van der Pol-type phononic crystals

Abstract The application of phononic chains as metamaterials demonstrates their remarkable capability to manipulate the propagation of waves. These periodic structures yield frequency-dependent behavior of material comprising characteristics with many possible engineering applications. In this paper, we investigate the weak and general nonlinear behaviors of the van der Pol-type damped phononic chains. The analysis of wave propagation is initially conducted for a one-dimensional structure, and subsequently, is extended to consider the wave motion through two-dimensional and three-dimensional lattices. Results are obtained using the method of multiple scales and a Spectro-spatial analysis by employing the numerical method of the 4th-order Runge–Kutta. A new phase-diagram relation within the chain’s unit cell is also introduced aiming to enhance the numerical findings. Our results indicate that in the weakly nonlinear regime, the van der Pol-type damping closely follows the linear dispersion curve, regardless of the initial amplitude. This suggests a symmetry between energy pumping and dissipation modes, where hardening and softening behaviors align with linear characteristics of common damping mechanisms, such as viscous damping. Additionally, the formulation demonstrates the existence of limit-cycle stability in the motion of each mass. For the general damped system, it is observed that a special frequency exists where the system converges, for all wave numbers similar to the synchronization effect. Hence, the motion and the frequency of all masses are synced. Additionally, non-reciprocal wave propagation is observed, resulting in a bandgap structure with a symmetry breaking occurring near the limit cycle. These results are promising in the fields of wave emitters, wave filters, and signal encryption.

Impact of Supply Chain Agility and Collaboration on Supply Chain Performance: The Moderating Role of Artificial Intelligence

Supply chain resilience is not a novel concept in the supply chain industry; however, its significance importance is increasing, especially in the face of global disruptive events like natural and man-made disasters. Agility and collaboration are critical supply chain resilience elements for enhancing supply chain performance. However, the influence of artificial intelligence (AI) on the impact of agility and collaboration on performance remains unexplored. Therefore, the major objective of this study was to examine the impact of supply chain agility and collaboration on supply chain performance within the healthcare sector in Qatar. In the same vein, it examined the moderating role of AI in these relationships. The study utilized 564 responses from supply chain and clinical unit managers in Qatar and was analysed using the partial least squares (PLS) path modelling technique. The findings of the study indicate a significant positive relationship between supply chain agility, collaboration, and performance. Furthermore, these relationships are found to be positively moderated by AI. This study supports the research paradigm and provides evidence regarding supply chain agility and collaboration and their impact on supply chain performance. More importantly, this study is among the first to provide empirical evidence on the moderating role of AI in enhancing these relationships.

Factors Affecting Quality of Health Care Services in Government Facilities in Kakindo Health Centre IV in Kakumiro District

This study aimed to examine the factors that affect quality of health services in Kakindo Health Center IV in Kakumiro District. The study used a cross-sectional design using a quantitative approach on the population which was under study. Data was collected using questionnaires, processed in excel, and word using SSP software for correlation purposes. The study found a high significant relationship between health-related factors, health worker related factors and quality of health service delivery. Patient related factors had a low significance. The study concluded that the quality of health services depends on the level to which the management of the facility provides the employees with a conducive work environment. appropriate knowledge and skills, and positive attitude of health workers towards patients was emphasized. health workers were argued to carry out daily patient education in order to change their traditional beliefs. Grading the facility to a level of Hospital this would help to build more infrastructure for both patients and staffs, for security of both patients and staff, the facility needs tapped water so that staff can access clean water inwards, especially the paediatric ward, theatre, general ward, outpatient department, A R T Clinic Cold chain unit and a few staff quarters. A proper fence must be put constructed at the facility. Keywords: Health service, Health workers, Patients, Delivery, Staff

Designing a Refined Multi-Structural Polymer Electrolyte Framework for Highly Stable Lithium-Metal Batteries.

Rational structural designs of solid polymer electrolytes featuring rich interface-phase morphologies can improve electrolyte connection and rapid ion transport. However, these rigid interfacial structures commonly result in diminished or entirely inert ionic conductivity within their bulk phase, compromising overall electrolyte performance. Herein, a multi-component ion-conductive electrolyte was successfully designed based on a refined multi-structural polymer electrolyte (RMSPE) framework with uniform Li+ solvation chemistry and rapid Li+ transporting kinetics. The RMSPEis constructed via polymerization-induced phase separation based on a rational combination of lithiophilic components and rigid/flexible chain units with significant hydrophobic/hydrophilic contrasts. Further refined by coating a robust polymer network, this all-organic design endows a homogenous micro-nano porous structure, providing a novel framework favorable for rapid ion transport in both its soft interfacial and bulk phases. The RMSPE exhibited excellent ion conductivity of 1.91 mS cm-1 at room temperature and a high Li+ transference number of 0.7. Assembled symmetrical Li cells realized stable cycling for over 2400 h at 3.0 mA cm-2. LiFePO4 full batteries demonstrated a long lifespan of 3300 cycles with a capacity retention of 93.5% and stable cycling performance at -35 °C. This innovative design concept offers a promising perspective for achieving high-performance polymer-based Li metal batteries.

Optimal establishment of processing unit and partner selection problem of perishable product supply chain: apple case study of India

Decentralized supply chain operation in India adds to inefficiency in management and control difficulties for perishable product supply chain (PPSC). One of the important categories of factors that underly the problem in supply chain is the establishment of processing units that results in end – product distribution. This paper presents an optimal establishment of processing unit around production area for apple supply chain as a case study of India. This study proposed amalgamation of mixed integer linear programming (MILP) and colored petri nets (CPN) to model the PPSC. The mathematical model was set up in regard with capacity of processing unit and transportation cost with continuation in partner selection using MILP approach. The simulation model directs the maximization of system performance by running in CPN environment. The values of the results are subjected to transportation cost and production area with estimate of 25% loss during post harvesting such as transportation and environmental variation. The results corresponding to the case study provided an optimal establishment of processing units. Further, the specific partner associated with the facility and transportation cost. Decision-makers can identify the set of partners from the set of facilities dependent upon the transportation cost for further supply of product using a threshold values. Thereby, the model can be used as a decision-making system for processing companies to result in efficient PPSC management. The developed model was tested and validated on case study to demonstrate our approach’s applicability.

An Antibacterial, Highly Sensitive Strain Sensor Based on an Anionic Copolymer Interpenetrating with κ-Carrageenan.

Polysaccharide-based hydrogels are suitable for use in the field of flexible bioelectronics due to their benign mechanical properties and biocompatibility. However, the preparation of hydrogel sensors with high performance without affecting their physicochemical properties (e.g., flexibility, toughness, self-healing, and antibacterial activity) remains a challenge and needs to be solved. Herein, a metal ion cross-linking reinforced, double network hydrogel was formed from a 2-acrylamide-2-methylpropanesulfonic acid (AMPS) copolymer interpenetrating κ-carrageenan (CAR), followed by immersing the gel in a Cu2+ ion solution to obtain an antibacterial CAR/P(AM-co-AMPS)-Cu2+ conductive hydrogel. LiCl was added as the electrolyte. The presence of the LiCl electrolyte and sulfonated molecular chain units not only gives the hydrogel good electrical conductivity (conductivity up to 2.68 S/m) but also improves the sensitivity of the hydrogel as a stress-strain sensor, with a hydrogel sensitivity GF of up to 3.76 in the 20%-100% strain range and response time of up to 280 ms. The CAR double-helical structure and sol-gel properties and the interaction of multiple noncovalent bonds between polymers provide the hydrogel with excellent self-healing, with a self-healing efficiency of 68%. In addition, the electrostatic interaction of Cu2+ with Escherichia coli cells can inhibit their growth, exhibiting good antibacterial properties with an inhibition circle diameter of 20.5 mm. This work could provide an effective strategy for antibacterial multifunctional CAR-based bionic sensors.

Design of pH/Redox Co-Triggered Degradable Diselenide-Containing Polyprodrug via a Facile One-Pot Two-Step Approach for Tumor-Specific Chemotherapy.

The diselenide bond has attracted intense interest for drug delivery systems (DDSs) for tumor chemotherapy, owing to it possessing higher redox sensitivity than the disulfide one. Various redox-responsive diselenide-containing carriers have been developed for chemotherapeutics delivery. However, the premature drug leakage from these DDSs was significant enough to cause toxic side effects on normal cells. Here, a pH/redox co-triggered degradable polyprodrug was designed as a drug self-delivery system (DSDS) by incorporating drug molecules as structural units in the polymer main chains, using a facile one-pot two-step approach. The proposed PDOX could only degrade and release drugs by breaking both the neighboring acid-labile acylhydrazone and the redox-cleavable diselenide conjugations in the drug's structural units, triggered by the higher acidity and glutathione (GSH) or reactive oxygen species (ROS) levels in the tumor cells. Therefore, a slow solubility-controlled drug release was achieved for tumor-specific chemotherapy, indicating promising potential as a safe and efficient long-acting DSDS for future tumor treatment.

Design of biocompatible gelatin hydrogels reinforced with magnetite nanoparticles: Effective removal of chromium from water environment

The development of biocompatible adsorbents is vital for environmental remediation to control and reduce pollution and waste accumulation in ecosystems. Biocompatible hydrogels represent an innovative class of materials that are primarily composed of polymer chain units forming their structural framework. They have a high affinity for water molecules. This research thus aims to incorporate iron oxide particles into the gelatin matrix to produce gelatin hydrogel beads to remove hexavalent chromium from an aqueous solution. The synthesized beads, known for their consistent size, low friction, high specific surface area, mechanical stability, and lightweight characteristics, demonstrated their suitability for various industrial applications. The effectiveness of these hydrogels in removing hexavalent chromium ions was confirmed through a thorough analysis using techniques such as FTIR, TGA, SEM, EDX, VSM, and XPS. Batch experiments revealed that the gelatin-based nanocomposite beads exhibited optimal adsorption efficiency under acidic conditions, lower initial concentrations of chromium ions, extended contact time, and elevated temperature (50–60 °C). The composite achieved a maximum removal efficiency of 99% at pH 1, with an adsorbent dose of 0.5 g at 50 °C, and an initial concentration of 50 mg per liter. The use of 0.7 N NaOH in the regeneration process resulted in a commendable 70.5% desorption efficiency, enabling potential reuse and regeneration. Significantly, the desorption efficiency remained consistently high even after four desorption-readsorption cycles, contributing to the economic and environmental sustainability of chromium removal. Additionally, the study determined that the sorption process was feasible, spontaneous, and endothermic. These collective findings suggest that magnetic gelatin hydrogel beads could serve as a cost-effective alternative adsorbent for the efficient removal of chromium ions from aqueous solutions.

Structural Engineering of l-Aspartic Amphiphilic Polyesters for Enzyme-Responsive Drug Delivery and Bioimaging in Cancer Cells.

Design and development of amphiphilic polyesters based on bioresources are very important to cater to the ever-growing need for biodegradable polymers in biomedical applications. Here, we report structural engineering of enzyme-responsive amphiphilic polyesters based on l-amino acid bioresources and study their drug delivery aspects in the cancer cell line. For this purpose, an l-aspartic acid-based polyester platform is chosen, and two noncovalent forces such as hydrogen bonding and side-chain hydrophobic interactions are introduced to study their effect on the aqueous self-assembly of nanoparticles. The synthetic strategy involves the development of l-aspartic acid-based dimethyl ester monomers with acetal and stearate side chains and subjecting them to solvent-free melt polycondensation reactions to produce side-chain-functionalized polyesters in the entire composition range. Postpolymerization acid catalyst deprotection of acetal yielded hydroxyl-functionalized polyesters. Amphiphilicity of the polymer is carefully fine-tuned by varying the composition of the stearate and hydroxyl units in the polymer chains to produce self-assembly in water. Various drugs such as camptothecin (CPT), curcumin (CUR), and doxorubicin (DOX) and biomarkers like 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS), rose bengal (RB), and Nile red (NR) are successfully encapsulated in the polymer nanoparticles. Cytotoxicity of biodegradable polymer nanoparticles is tested in normal and breast cancer cell lines. The polymer nanoparticles are found to be highly biocompatible and delivered the anticancer drugs in the intracellular compartments of the cells.

A comparative study of mechanical crushing and pyrolysis techniques for separation and recovery of discarded polycrystalline silicon photovoltaic modules

With the rapid growth of the photovoltaic (PV) industry, efficient recovery and utilization of discarded polycrystalline silicon PV modules have attracted increasing attention. This study compares the application of mechanical crushing and pyrolysis techniques in the recovery of PV modules. The results indicate that while mechanical crushing can preliminarily disintegrate materials, its effectiveness in separating valuable materials such as silver and aluminum is limited, particularly for particles larger than 1 mm. In contrast, pyrolysis techniques demonstrate outstanding performance in removing organic matter and separating silicon wafers and glass, notably enhancing the recovery rate of large glass particles. However, the brittleness of silicon wafers presents a challenge during pyrolysis. Furthermore, the pyrolysis mechanisms of ethylene-vinyl acetate (EVA) film and backsheet materials are thoroughly discussed. The pyrolysis process of EVA film involves two stages: firstly, the preferential decomposition of acetyl oxygens on ester side chains, followed by further pyrolysis decomposition of the main chain and side chains to generate alkanes. Pyrolysis of polyethylene terephthalate (PET) begins with the generation of methyl and benzoyl radicals, while polyvinyl fluoride (PVF) and polyvinylidene fluoride (PVDF) pyrolysis initiates with the detachment of head-group units, followed by sequential detachment of chain units. Given the advantages of pyrolysis techniques, this study recommends them as the preferred method for PV module recovery.

How syntactic complexity indices predict Chinese L2 writing quality: An analysis of unified dependency syntactically-annotated corpus

Previous syntactic complexity (SC) research on L2 Chinese has overlooked a range of Chinese-specific structures and fine-grained indices. This study, utilizing a syntactically annotated Chinese L2 writing corpus, simultaneously employs both large-grained and fine-grained syntactic complexity indices to investigate the relationship between syntactic complexity and writing quality produced by English-speaking Chinese second language (ECSL) learners from macro and micro perspectives. Our findings reveal the following: (a) at a large-grained level of analysis using syntactic complexity indices, the generic syntactic complexity indice (GSC indice) number of T-units per sentence and the Chinese-specific syntactic complexity indice (CSC indice) number of Clauses per topic chain unit account for 14.5% of the total variance in writing scores among ECSL learners; (b) the syntactic diversity model alone accounts for 24.7% of the variance in Chinese writing scores among ECSL learners; (c) the stepwise regression analysis model, which integrates fine-grained SC indices extracted from the syntactically annotated corpus, explains 43.7% of the variance in Chinese writing quality. This model incorporates CSC indices such as average ratio of dependency types per 30 dependency segments, the ratio of adjuncts to sentence end, the ratio of predicate complements, the ratio of numeral adjuncts, the mean length of Topic-Comment-Unit dependency distance, as well as GSC indices like the ratio of main governors, the ratio of attributers, the ratio of coordinating adjuncts, and the ratio of sentential objects. These findings highlight the valuable insights that syntactically annotated fine-grained SC indices offer regarding the writing characteristics of ECSL learners.

Implementation of the Su-Schrieffer-Heeger Model in the Self-Assembly Si-In Atomic Chains on the Si(553)-Au Surface.

Indium-decorated Si atomic chains on a stepped Si(553)-Au substrate are proposed as an extended Su-Schrieffer-Heeger (SSH) model, revealing topological end states. An appropriate amount of In atoms on the Si(553)-Au surface induce the self-assembly formation of trimer SSH chains, where the chain unit cell comprises one In atom and two Si atoms, confirmed by scanning tunneling microscopy images and density functional calculations. The electronic structure of the system, examined through scanning tunneling spectroscopy, manifests three electron bands within the Si-In chain, accompanied by additional midgap topological states exclusively appearing at the chain's end atoms. To elucidate the emergence of these topological states, a tight-binding model for a finite-length-extended SSH chain is proposed. Analysis of the energy spectra, density of states functions, and eigenfunctions demonstrates the topological nature of these self-assembled atomic chains.

Temperature effects and molecular insights towards the optimization of polyvinyl alcohol as adsorbent of organic pollutants from aqueous solution

One of the easier methods of wastewater treatment is adsorption due to its simplicity in implementation, environmental friendliness, and economic feasibility. Polyvinyl alcohol (PVA) looks promising as an adsorbent due to its biocompatible, non-toxic, water-soluble and eco-friendly nature. The investigation of PVA for its potential in the adsorption of pollutants has been reported in many studies but the mechanistic understanding of the adsorption is poor. The present study used a theoretical approach through density functional theory and Monte Carlo with molecular dynamics simulations to investigate the adsorption mechanism behaviors of model organic molecules (bromothymol blue (BTB), methylene blue (MB), metronidazole (MNZ) and tetracycline (TC)) on PVA surface. The quantum chemical calculations result showed that with the increase in PVA chains (2, 4, 8, 16, and 32 units), the zero-point energy decreases (from −308.79 to −4922.93 kcal/mol) while the dipole moment increases (from 4.37 to 87.52 Debye). Temperature effect on the PVA chain structures showed the same trends for all the chain units and with the increase in temperature (50–600 K), there are no appreciable changes in zero-point energy, enthalpy energy increases while Gibbs free energy decreases. Considering PVA-pollutant complexes, the effects of temperature on the structures showed that there are no appreciable changes in the zero-point energy, Gibbs free and thermal energies increase with an increase in temperature while the kinetic rate of reactions decreases with an increase in temperature. The enthalpy of the reaction showed different trends with antibiotic and dye complexes. In all the thermodynamic properties investigated and the rate of reaction, the order of affinity of the pollutants with PVA followed TC > MNZ > MB > BTB. Monte Carlo simulation was used to investigate the adsorption behavior of the pollutants on the surface of PVA. The negative adsorption energies (−366.56 to −2266.81 kcal/mol) in terms of affinity towards the pollutants on the surface of PVA followed the sequence TC > MNZ > BTB > MB and the molecular dynamic simulation results followed the same order. The obtained results give valuable insights into the mechanism and performance of PVA as an adsorbent. Most of these computational observations are in good agreement with the available experimental results.

Cross-coupling and dehalogenation reactions of novel π-conjugated polymers bearing high-soluble coumarin unit in the main chain and their acid-base responsive fluorescence

A highly soluble coumarin monomer, 3,7-dibromo-4-octyloxycoumarin, was developed as the novel building block for π−conjugated polymers. Sonogashira coupling reaction, dehalogenation reaction, and Suzuki-Miyaura coupling reaction were carried out by using this new monomer as the main chain unit of π−conjugated polymer for polymerization. Introduction of a long alkoxy chain into coumarin monomer unit significantly improved the solubility of thus obtained polymers. The absorption and emission spectra of polymers showed red-shift compared to those of monomer, indicating the expansion of the π−conjugated system in the polymer main chain. Especially the polymers synthesized via Sonogashira coupling formed excimer in film state. The polymers showed acid-base responsibility with the addition of KOHaq and HClaq.

The Role of Ecotourism in Reducing Poverty and Unemployment: A Mixed Method Approach

Ecotourism is perceived as a promising initiative capable of poverty alleviation and job creation. This study investigated whether ecotourism helps to alleviate poverty and unemployment in relatively underdeveloped areas such as the UMkhanyakude district municipality. The study used a parallel, convergent research design comprising qualitative and quantitative research applications. Both random and purposive sampling techniques were used to select a sample of 204. In selecting respondents for the quantitative dimension, two types of databases obtained from each of the local municipalities were used. The first database comprised community registers, and the second included a list of companies registered with the municipality’s supply chain or procurement unit. Specifically, the criteria used to select participants included expertise, understanding of ecotourism programme implementation processes, skills, and proximity to ecotourism projects. Four (n = 4) officials and four (n = 4) program managers, for a total of eight, were selected from each of the four local municipalities. This resulted in a combined purposive sample of 32 participants (8 x 4 = 32) for the interviews. The Statistical Package for the Social Sciences (SPSS) was employed to analyse quantitative data. The qualitative data were processed through the ATLAS TI application. From the results, it can be deduced that, to a greater extent, ecotourism is contributing towards the reduction of poverty and unemployment in UMkhanyakude District Municipality. Based on the results, it can be concluded that ecotourism has the potential to reduce poverty and unemployment in rural communities in line with the dimensions of sustainable development goals. Benchmarking activities that focus on community roles and responsibilities, awareness-building strategies at the community level, stakeholder consultation and involvement, and capacity-building programmes are recommended.

Enhanced quantum transport in chiral quantum walks

Quantum transport across discrete structures is a relevant topic that can be suitably studied in the context of continuous-time quantum walks. The addition of phase degrees of freedom, leading to chiral quantum walks, can also account for directional transport on graphs with loops. We discuss criteria for quantum transport and study the enhancement that can be achieved with chiral quantum walks on chain-like graphs, exploring different topologies for the chain units and optimizing over the phases. We select three candidate structures with optimal performances and we investigate their transport behaviour with Krylov reduction. While one of them can be reduced to a weighted line with minor couplings modulation, the other two are truly chiral quantum walks, with enhanced transport probability over long chain structures.

Preparation and characterization of isotactic polypropylene-based block copolymers with cyclic units

Olefin block copolymer is one class of promising high-end material that has the potential to combine the performance advantages of individual blocks. In this work, a series of isotactic polypropylene (iPP)-based diblock copolymers was designed and synthesized by coordinative chain transfer polymerization using a dimethyl(pyridylamido)hafnium/[Ph3C][B(C6F5)4]/AliBu3 catalytic system. The prepared diblock copolymers were composed of the regular iPP segments and the propylene/1,5-hexadiene (1,5-HD) random segments. The incorporated 1,5-HD existed exclusively as methylene-1,3-cyclopentane units in the polymer chains, because of the complete cyclization selectivity of the employed dimethyl(pyridylamido)hafnium catalyst. These block copolymers possessed high melting temperatures over 158 °C. Moreover, the block copolymers exhibited remarkably improved mechanical properties with respect to iPP, which could be systematically tuned by adjusting the content of 1,5-HD. In the 1,5-HD content range of 3.4–11.0 mol%, the block copolymers exhibited both high yield stress and high elongations at break. The copolymerization approach of block copolymers provided an effective method to achieve the strength-ductility balance of iPP-based copolymers.

Factors Affecting Quality of Health Care Services in Government Facilities in Kakindo Health Centre IV in Kakumiro District

This study aimed to examine the factors that affect quality of health services in Kakindo Health Center IV in Kakumiro District. The study used a cross-sectional design using a quantitative approach on the population which was under study. Data was collected using questionnaires, processed in excel, and word using SSP software for correlation purposes. The study found a high significant relationship between health-related factors, health worker related factors and quality of health service delivery. Patient related factors had a low significance. The study concluded that the quality of health services depends on the level to which the management of the facility provides the employees with a conducive work environment. appropriate knowledge and skills, and positive attitude of health workers towards patients was emphasized. health workers were argued to carry out daily patient education in order to change their traditional beliefs. Grading the facility to a level of Hospital this would help to build more infrastructure for both patients and staffs, for security of both patients and staff, the facility needs tapped water so that staff can access clean water inwards, especially the paediatric ward, theatre, general ward, outpatient department, A R T Clinic Cold chain unit and a few staff quarters. A proper fence must be put constructed at the facility. Keywords: Health service, Health workers, Patients, Delivery, Staff.

STUDY OF THE EQUILIBRIUM POSITION OF THE MECHANISMS
 OF THE WORKING CHAMBER OF A CHAIN UNIT

The object of study in the article is the working chamber of the chain unit. We consider its previously proposed threerod
 model in the equilibrium position under the influence of gravity, the shape of which was determined using the angular
 parameters αл and αп borrowed from experience. Here, in a new study, a variant of the analytical determination of these
 parameters is proposed. To achieve the goal, transcendental equations are obtained and an algorithm for the successive
 approximation method is developed to solve them. An algorithm used for numerical studies of the nature of changes in angles
 αл, αп depending on the ratio of gravity forces applied in kinematic pairs and the crank rotation angle. The corresponding
 graphs have been built. It has been established that the inclination of the plane of movement of the working parts of the
 chamber does not affect the angular parameters obtained for the equilibrium position in the vertical plane.