Middle Chamber Research Articles

Effect of External load and Salt Concentration on the Performance of Microbial Desalination Cell

Microbial desalination cell (MDC) is one of the cost and energy effective methods that can help people in countries with low income and people in rural areas without energy infrastructure, get access to desalinated water while treating their wastewater. Despite the advantages of the technology, less is known about the behavior of the internal resistance in MDCs. Therefore, this study mainly focused on the behavior of the MDC from internal and external resistance point of view. The desalination rate of saltwater at different applied external resistance (995 , 464 , 220 , and 74 ) was studied. Moreover, the polarization capacity of the established MDC was investigated. The internal resistance of MDC at different salt concentrations of the desalination chamber (35-1 g/l) was also analyzed and discussed. The findings of the study showed that decreasing the external resistance could increase the current generation of the MDC as the main driving force of the desalination. Furthermore, it was found that salt concentration in the middle chamber plays a significant role on the internal resistance of MDC and hence on the desalination rate. Lower desalination rate at the lower salt concentration of the desalination chamber could be explained by the high internal resistance of the system. Therefore, integrating MDC with other suitable techniques, e.g., reverse osmosis (RO), for desalination of lower salt concentrations could overcome this challenge. MDC as a standalone desalination system at the current stage of technology might not be practical due to the low current performance of the system. However, it is worth considering it as green and low-cost technology for the pretreatment stage of the other conventional desalination systems, like RO with energy and cost savings while treating the wastewater.

Saturated buffer design flow and performance in Illinois.

There are few peer-reviewed studies documenting saturated buffer annual nitrate (NO3 ) removal or that have assessed the federal practice standard design criteria. Drainage flow, NO3 , and dissolved reactive phosphorus (DRP) were monitored at three saturated buffers in Illinois, USA, for a combined 10 site-years. Nitrate loss reduction averaged 48 ± 19% with removals of 3.5-25.2kg NO3 -N ha-1 annually. Median DRP concentrations at all sampling locations were at the analytical detection limit of 0.01mg L-1 . The current design paradigm (i.e., USDA practice standard) prescribes there should be no flow bypassing the saturated buffer at flow rates that are ≤5% of the peak drainage system flow rate. The drainage coefficient-based and Manning's equation-based peak flow estimates were higher and lower, respectively, than the observed annual peaks in all years. This illustrated inherent uncertainty introduced early in the design process, which can be further compounded by dynamic in-buffer hydrology. The percentage of the observed peak flow rate at which bypass initiated ranged across an order of magnitude between sites (4.4-8.1% of peak flow rate at one site and 42-49% of peak at another) despite the buffers providing relatively similar NO3 removal. Bypass at one site (SB2) was related to the concept of "antecedent buffer capacity filled," which was defined as the 5-d average water depth in the middle control structure chamber expressed as a relative percentage of the bypass stop log height. This design flow analysis serves as a call to further evaluate predictive relationships and design models for edge-of-field practices.

Performance of recirculatory Microbial Desalination Cell-Microbial Electrolysis Cell coupled system with different catholytes

Microbial Desalination Cell-Microbial Electrolysis Cell (MDC-MEC) coupled system, are very important and efficient in several processes including wastewater treatment; heavy metal removal; desalination; and chemical production. The performances of ferricyanide (MDCF) and 100 mM potassium phosphate buffer (MDCP100) as catholytes in the MDC were tested over a fed-batch cycle. The MDC systems (MDCF and MDCP100) were coupled with MEC to determine their effect on Pb and Fe removal. The COD removal efficiencies in MDCF, MDCP100, and control 1 were 92.96%, 90.54%, and 89.03% respectively. All the MDC systems were able to achieve a very high Pb2+ and Fe2+ removal efficiency, >90%. A high cathodic reduction potential was reached and maintained by the MDC-MEC systems, enable the reduction of Pb2+ and Fe2+ to Pb and Fe metals, through precipitation at the cathode of the MEC. MDCF had higher current and power densities of 550 mAm−2 and 166.08 mWm−2 respectively than that of MDCP100. More wastewater can be treated in the MDCP100 for ammonium removal in the middle chamber than that of MDCF. Therefore, the volume ratio of COD and NH4Cl removal in the MDC for balanced COD/Ammonium ions removal is a key driving force to the Industrial scale-up of the coupled system.

Y(III) Ion Migration in AlF3–(Li,Na)F–Y2O3 Molten Salt

In this study, three slots containing an anode chamber, a cathode chamber, and a middle pole chamber were designed by applying the Hittorf method, and a two-way coupling model of the flow field and electric field was established using the COMSOL system. The electric field distribution in the constructed model was simulated, and the model reliability, boundary conditions, and related parameters were verified. A three-chamber tank was utilized to investigate the migration numbers change rule and migration mechanism of Y(III) ions in the AlF3–(Li,Na)F system. The migration number of Y(III) ions in the AlF3–(Li,Na)F–Y2O3 molten salt linearly increased from 0.70 to 0.80 with an increase in temperature from 900 to 1000 °C. When the (Li,Na)F/AlF3 molar ratio was between 2.0 and 2.5, the migration number of Y(III) ions was relatively constant, and its average value was approximately 0.75. Meanwhile, at (Li,Na)F/AlF3 molar ratios higher than 2.5, the migration number of Y(III) ions linearly decreased from 0.75 to 0.45. Finally, in the current density range of 1.0–2.0 A/cm2, the migration number of Y(III) ions increased almost linearly from 0.65 to 0.85.

Combined effect of intake angle and chamber structure on flow field and combustion process in a small-scaled rotary engine

This work aims to reveal combined effect of intake angle and chamber structure on flow field, flame propagation, combustion characteristics and pollutants formation of a small-scaled rotary engine by using numerical simulation. For this reason, a three-dimensional dynamic simulation model was established by using a reasonable turbulent model and choosing a reduced reaction kinetic mechanism and was also validated by the experimental data. Simulation results showed that intake angle is more significant to the influence of flame propagation, in-cylinder pressure and heat release rate (HRR) in the front baffle combustion chamber (FBCC) and the rear baffle combustion chamber (RBCC) compared to that in the middle baffle combustion chamber (MBCC), but is an opposite trend for effect of flow field. The differences in the in-cylinder velocity field and turbulent kinetic energy magnitude were the intrinsic mechanism of combined influence of intake angle and chamber structure. Under larger intake angle, for the MBCC and the RBCC, higher pressure, HRR and power output were obtained, meanwhile the decreased HC and CO formations were obtained, while showed a contrary tend for the FBCC. And the amount of HC formation for these three combustion chambers at 15°intake angle is relatively small. To sum up, considering combustion characteristics, engine cooling and pollutants formation, it can be concluded that the combination of 15°intake angle and combustion chamber with a middle baffle was the optimum configuration for a small-scaled RE in engineering application. • The recess shape of rotor and intake angle are optimized. • Intake angle is more significant to the influence of combustion in FBCC and RBCC. • Recess shape plays a more significant role in effect of flow field and combustion. • Larger flow velocity and TKE near the spark plugs improve initial flame development. • The optimal scheme is the combination of 15° intake angle and MBCC or RBCC.

Research on the Application Performance of the Helmholtz High-Efficiency Wave-Elimination Chamber in Gas Wave Tubes

A gas wave refrigerator is a device that uses gas pressure to expand and refrigerate; the moving shock wave in the gas wave tube is the key to cooling. If the shock wave is reflected to the open mouth of the gas wave tube, it will heat the expanded refrigeration gas at the open end, severely reducing the refrigeration efficiency. In order to reduce this effect, a Helmholtz middle wave chamber-type gas wave tube is presented here. This study describes the performance of this structure in the gas wave refrigeration process. The refrigeration performance of the structure’s gas wave tube use was evaluated experimentally and numerically using computational fluid dynamics (CFD). The function of the middle wave elimination chamber was studied and explained: the chamber turns the reflected shock wave back to the end section of the tube and converts part of the incoming shock wave to an expansion wave, which may counteract the reflected shock wave by escaping from wave elimination chamber. The experimental results showed that the structure increased refrigeration efficiency by about 2.9% (50 Hz), 2% (40 Hz), and 2.2% (25 Hz) at the corresponding ejection frequencies, and reduced the reflected shock wave intensity by 11%, which proves the high-efficiency energy dissipation performance and the significant increase in refrigeration efficiency of the Helmholtz-type gas wave tube.

Otosclerosis: Etiology and Prognostic Factors

Otosclerosis is a temporal bone osseous dyscrasia that causes auditory impairment over time. Aberrant growth of a new bone in the middle ear eventually immobilizes and stops the stapes from oscillating in reaction to sound vibrations, resulting in gradual and persistent hearing impairment. Both ears are generally affected by the disease. Otosclerosis is a rapid occurrence of unexplained facial nerve palsy. With just an estimated prevalence of 15-30 per 100,000, it would be the most prevalent reason for lower motor neuron facial nerve paralysis. There are broadly two types of Otosclerosis, namely histological and clinical Otosclerosis. A minor incidence of Bell's palsy usually goes away in about a fortnight. It takes to recover from a more severe instance of complete paralysis varies. Among the potential complications are. Multiple sclerosis, Miller-Fisher syndrome, Guillain–Barré syndrome, and autoimmune encephalitis are autoimmune diseases. In patients with otitis media, malignant otitis externa damage to your facial nerve is irreversible.
 Nerve fiber regrowth is abnormal. When you try to move others, specific muscles may contract involuntarily (synkinesis) – for example, when you grin, the eye on the afflicted side may shut.
 Due to prolonged dryness and scratching of the transparent protective coating of the eye (cornea), the eye becomes wholly or partially blind.
 Patients report fast and increasing symptoms over a day to a week, with a 72-hour maximum severity. One-half of the face will be weak, resulting in eyebrows, forehead, and mouth angle instability. The incapacity to shut the afflicted eyelid or lip on the affected side is a common symptom. A partial or total weakening of the forehead is the most apparent physical exam finding. If the integrity of the forehead is preserved, a significant reason should be looked into. Most of the cases of Otosclerosis have idiopathic or unknown causative agents. In some patients with Otosclerosis, a sponge-like bone grows abnormally in the middle ear chamber. Because of this expansion, the ear bones cannot vibrate in response to acoustic pressure.

New superjelly can go from squishy to ultrahard

Like a water balloon bursting when squeezed, most soft hydrogels will squish into pieces when compressed. Now, for the first time, researchers have created a superjelly with properties that range from rubber-like and squishy at rest to glass-like, ultrahard, and shatterproof when compressed ( Nat. Mater. 2021, DOI: 10.1038/s41563-021-01124-x ). Despite its 80% water content, the hydrogel can be run over by a car and bounce back to its original form. The team, led by Oren Scherman of the University of Cambridge, designed a synthetic polymer with a cross-linking molecule called a cucurbituril, which has a barrel-shaped middle chamber that holds two different guest molecules . Driven by their affinities for the curcubituril cavity and each other, the guest molecules continually go in and out of the chamber, dissipating the stress put on the material. After testing many kinds of electron-donating guest molecules, the researchers found that they could dramatically

Customizable Microfluidic Origami Liver-on-a-Chip (oLOC).

The design and manufacture of an origami-based liver-on-a-chip device are presented, together with demonstrations of the chip's effectiveness at recapitulating some of the liver's key in vivo architecture, physical microenvironment, and functions. Laser-cut layers of polyimide tape are folded together with polycarbonate nanoporous membranes to create a stack of three adjacent flow chambers separated by the membranes. Endothelial cells are seeded in the upper and lower flow chambers to simulate sinusoids, and hepatocytes are seeded in the middle flow chamber. Nutrients and metabolites flow through the simulated sinusoids and diffuse between the vascular pathways and the hepatocyte layers, mimicking physiological microcirculation. Studies of cell viability, metabolic functions, and hepatotoxicity of pharmaceutical compounds show that the endothelialized liver-on-a-chip model is conducive to maintaining hepatocyte functions and evaluation of the hepatotoxicity of drugs. Our unique origami approach speeds chip development and optimization, effectively simplifying the laboratory-scale fabrication of on-chip models of human tissues without necessarily reducing their structural and functional sophistication.

Sex differences in risk behavior parameters in adolescent mice: Relationship with brain-derived neurotrophic factor in the medial prefrontal cortex

Adolescence is as a period of development characterized by impulsive and risk-seeking behaviors. Risk behaviors (RB) involves exposure to dangerous or negative consequences to achieve goal-directed behaviors, such as reward-seeking. On the other hand, risk aversion/assessment behaviors allow the individual to gather information or avoid potentially threatening situations. Evidence has suggested that both behavioral processes, RB and risk assessment (RA), may have sex-differences. However, sex-specific behavioral patterns implicated in RB and RA are not fully understood. To address that, we investigated sex differences in risk-behavioral parameters in a decision-making task developed for rodents. In addition, we investigated the potential role of sex-dependent differences in gene expression of brain-derived neurotrophic factor (BDNF) exon IV in the medial prefrontal cortex (mPFC), which has been implicated to mediate PFC-related behavioral dysfunctions. Male and female C57BL/6J adolescent mice were evaluated in the elevated plus-maze (EPM) to assess anxiety-like behaviors and in the predator-odor risk taking (PORT) task. The PORT task is a decision-making paradigm in which a conflict between the motivation towards reward pursuit and the threat elicited by predatory olfactory cues (coyote urine) is explored. After behavioral testing, animals were euthanized and BDNF exon IV gene expression was measured by RT-qPCR. Comparative and correlational analyses for behavioral and molecular parameters were performed for both sexes. We observed that female mice spent more time exploring the middle chamber of the PORT apparatus in the aversive condition, which is an indicative of avoidance behavior. Female mice also had a higher latency to collect the reward than male mice and presented less time exploring the open arms of the EPM. BDNF exon IV gene expression was higher among females, and there was a positive correlation between the BDNF and PORT behavioral parameters. Our findings suggest sex-dependent effects in the PORT task. Females presented higher RA and avoidance behavior profile and expressed higher levels of BDNF exon IV in the mPFC. Moreover, higher BDNF expression was correlated with RA behaviors, which suggests that adolescent females tend to evaluate the risks more than adolescent males and that BDNF gene expression may be mediating decision-making processes.

Development of a vuilleumier refrigerator with crank drive mechanism based on experimental and numerical study

• Development of Vuilleumier refrigerator by theoretical and experimental methods. • A real Vuilleumier refrigerator is built and tested. • At 22 bar, 600 rpm, operating temperatures 900 K and 276 K, 221 K is reached. • A novel thermodynamic model is developed and validated. The present paper is focused on development of the thermodynamic model and a heat-driven Vuilleumier refrigerator. Thermodynamic properties and performance are predicted by thermodynamic model. On the other hand, a prototype Vuilleumier refrigerator with crank drive mechanism is built and the performance is measured. In the thermodynamic model, the refrigerator is divided into five working spaces for analysis, including hot chamber, hot regeneration chamber, middle chamber, cold regeneration chamber and cold chamber. Also, the influence of clearance leakage between middle chamber and buffer chamber is investigated. The effects of geometrical parameters, charged pressure, rotating speed, heating temperature, cooling temperature and heat loading on the cold head temperature are evaluated. In addition, the numerical results and the experimental data under different operating parameters are compared for model validation. As the Vuilleumier refrigerator operated at 22 bar pressure, 600 rpm rotating speed, 900 K heating temperature and 276 K cooling temperature, the cold head can reach a zero-load temperature of 221 K. When a 0.7 W heating load is applied on the cold head, cold head temperature of 252.6 K and coefficient of performance of 0.0068 can be obtained.

Performance of Recirculatory Microbial Desalination Cell-Microbial Electrolysis Cell Coupled System with Different Catholytes

Microbial Desalination Cell-Microbial Electrolysis Cell (MDC-MEC) coupled system, are very important and efficient in several processes including wastewater treatment; heavy metal removal; desalination; and chemical production. The performances of ferricyanide (MDCF) and 100mM potassium phosphate buffer (MDCP100) as catholytes in the MDC were tested over a fed-batch cycle. The MDC systems (MDCF and MDCP100) were coupled with MEC to determine their effect on Pb and Fe removal. The COD removal efficiencies in MDCF, MDCP100, and control 1 were 92.96%, 90.54%, and 89.03% respectively. All the MDC systems were able to achieve a very high Pb2+ and Fe2+ removal efficiency, >90%. A high cathodic reduction potential was reached and maintained by the MDC-MEC systems, enable the reduction of Pb2+ and Fe2+ to Pb and Fe metals, through precipitation at the cathode of the MEC. MDCF had higher current and power densities of 550 mAm-2 and 166.08 mWm-2 respectively than that of MDCP100. More wastewater can be treated in the MDCP100 for ammonium removal in the middle chamber than that of MDCF. Therefore, the volume ratio of COD and NH4Cl removal in the MDC for balanced COD/Ammonium ions removal is a key driving force to the Industrial scale-up of the coupled system.

Optimization of Nonlinear Pressure-Flow Characteristics of a Spring-Loaded Pressure Relief Valve Based on Computational Fluid Dynamics Simulation

Abstract In this study, the nonlinear pressure-flow characteristics of a spring-loaded pressure relief valve (PRV), which is used in the automotive fuel supply system for pressure control is analyzed, and its characteristics are improved by means of geometrical modifications of the valve structure. Given the complexity of the coupling mechanism between the valve internal flow characteristics and spring system, a quasi-steady computational fluid dynamics (CFD) method is introduced to predict the nonlinear pressure-flow characteristic curve of the valve and the accuracy is validated by experimental data. The total hydraulic force on the valve spool and diaphragm are divided into three parts according to the loading position and the correlation between the internal flow characteristics, hydraulic force, and pressure-flow characteristics of the valve are explained by CFD analysis and visualization. The results show that the quasi-steady CFD method can accurately predict the trends of the valve nonlinear pressure-flow characteristic curve, which is mainly determined by the hydraulic force produced in the middle chamber of the valve. When the valve opening reaches a certain value, a main vortex would be formed in the middle chamber and lead to the sudden increase of hydraulic force which causes the fluctuation of the pressure-flow characteristic curve of the valve. It is also found that the toggle point for the flow regimes seen in the valve is affected by the geometric structure of the middle chamber and the pressure-flow characteristics can be improved by the round corner size modification.

Spacecraft hatch leak testing

Spacecraft hatch needs to be tested for leakage in various environments. Hatch Quick Leak Detector (HQLD) leak testing method is a convenient and effective method for the orbital hatch. Vacuum Chamber leak testing (VCLT) method is a proper integral leakage rate method for the hatch. We performed the testing in the “CMK2000” vacuum vessel. The detection principles and steps are described in detail. Leak testing was performed on all of the hatch seals using helium mass spectrometer leak detectors and special apparatus under the Thermal Vacuum testing. We performed leak testing after finishing operating the hatch in the Thermal Vacuum environment. The relative uncertainty of the total leakage rate value of the hatch is 23.6% (k = 2). The total leakage rate testing was a successful example of complex quantitative leakage rate testing in a middle vacuum chamber.

Effect of modified anode on bioenergy harvesting and nutrients removal in a microbial nutrient recovery cell

The microbial nutrient recovery cell i.e. modified microbial fuel cell containing a middle recovery chamber can be used to purify wastewater and remove valuable nutrients, while simultaneously generating electricity. The study investigated nutrient removal and microorganism interactions with carbon (CB- HT and CB- APTES) and stainless steel (SSB-HT) modified anodes used in microbial nutrient recovery cells. The removal efficiencies of ammonium ions were found higher in carbon-based CB-APTES (~98%) and CB-HT (~98.27%) systems in comparison to SSB-HT (~87.16%) system. On comparing further, the removal efficiencies of chemical oxygen demand (~99.5%) and total phosphorus (~99%) in CB- APTES system were superior to the cases of CB- HT, and SSB- HT systems. Besides, the CB-APTES based microbial fuel cell (MFC) displayed an average stable voltage of 0.5 V and a maximum power density of ~ 850 mW/m2.

Social preference in rats.

Rats were given repeated choices between social and nonsocial outcomes, and between familiar and unfamiliar social outcomes. Lever presses on either of 2 levers in the middle chamber of a 3-chamber apparatus opened a door adjacent to the lever, permitting 45-s access to social interaction with the rat in the chosen side chamber. In Experiment 1, rats preferred (a) social over nonsocial options, choosing their cagemate rat over an empty chamber, and (b) an unfamiliar over a familiar rat, choosing a non-cagemate over their cagemate. These findings were replicated in Experiment 2 with 2 different non-cagemate rats. Rats preferred both non-cagemate rats to a similar degree when pitted against their cagemate, but were indifferent when the 2 non-cagemates were pitted against each other. Similar preference for social over nonsocial and non-cagemate over cagemate was seen in Experiment 3, with new non-cagemate rats introduced after every third session. Response rates (for both cagemate and non-cagemate rats) were elevated under conditions of nonsocial (isolated) housing compared to conditions of social (paired) housing, demonstrating a social deprivation effect. Together, the experiments contribute to an experimental analysis of social preference within a social reinforcement framework, drawing on methods with proven efficacy in the analysis of reinforcement more generally.

Bioelectrochemically assisted sustainable conversion of industrial organic wastewater and clean production of microalgal protein

Chlorella vulgaris, one of the single cell protein sources, is a promising alternative to address the ever-growing demand for food-quality protein. Efforts have been made to overcome the high production costs by using wastewater for the cultivation of C. vulgaris. However, direct use of wastewater poses threats to the safety of applying the obtained biomass for food and animal feed. This study applied a novel three-chamber microalgal-bio-electrochemical systems for simultaneous clean cultivation of C. vulgaris and treatment of industrial organic wastewater. Results demonstrated that the removal of COD (38.7–66.8%) and total Kjeldahl nitrogen (TKN, 49.8–69.0%) improved with the increase of electric current in both anode and cathode chambers. Meanwhile, comparable phosphorus removal rates of 34.2–48.5% were achieved in all operation modes. Through nutrients migration, the middle chamber recovered 34.4–39.4% TKN, 16.8–47.3% phosphorus, and acetate from the wastewater to support a mixotrophic growth of C. vulgaris. Moreover, increasing electric current promoted higher dry algal biomass weight (0.87–1.11 g L−1), higher protein content (320.8–552.1 mg Protein g−1 Biomass), and larger cell size (enlarged up to 151.2%) than the control. Nevertheless, the ratio of protein content decreased with the increase of cell size due to the prior accumulation of other compounds under mixotrophic growth. This study provides a sustainable approach for the conversion from industrial organic wastewater to clean production of microalgal protein.

Electrochemical desalination coupled with energy recovery and storage

This paper presents the performance of a dual-purpose Zinc|ferricyanide desalination battery for simultaneous desalination and energy storage operations. The zinc|ferricyanide battery consists of an anode chamber with a zinc electrode immersed in ZnCl2(aq) electrolyte, a cathode chamber with a graphite electrode and electrolyte solution of K3[Fe(CN)6](aq) and K4[Fe(CN)6](aq), as well as a middle chamber with saline water to be desalinated. These chambers are separated by anionic and cationic exchange membranes, respectively. A series of experiments were conducted to study the impact of charging and discharging cycles on desalination-salination rates, power storage, and discharge rates at different charging capacities. The electrochemical cell was also characterized in terms of power density and desalination performance under various conditions. Results from this study confirm that the electrochemical battery desalination method has the potential to store energy and the charging-discharging cycles of the battery can provide a mechanism for desalination, which is achieved free of energy consumption. A desalination rate of 30.3% can be achieved during a 12-hr discharge period, which decreased the salinity levels from 41.2 g/L to 28.7 g/L. This result indicates that the process is also suitable for pre-desalination or pretreatment of high saline waters, which is a major challenge for current membrane processes.

Application and Research of the Particle Element Model in Ignition Process of Large-Particle High-Density Charge

ABSTRACT In order to describe the movement characteristics of large-particle high-density charge and the development process of flow field and flame spreading in the chamber, a new modified and simplified particle element model was established based on Eulerian-Lagrangian approach, and the gas governing equations are discretized with the fifth-order WENO scheme. The experiment was carried out on the visualized experiment platform, and the relevant data were recorded by the data acquisition instrument and high-speed photography system. The results show that the numerical simulation results are in good agreement with the experiment, and the particle element model describes the process of particle motion accurately, which indicated that the problem of flow characteristics in the period of ignition and flame spreading in high-density charge solved effectively by the model. In the initial period of the ignition, the particles in the high-density charging bed moved slowly, and the law of the particles almost the same. The pressure in the middle chamber fluctuates obviously when the particles start to move. The gap in high-density charge would lead to throttling of the discontinuity surface, resulting in pressure fluctuation at the interface and the discontinuity surface of gas-phase velocity. The effects of different ignition and charging conditions on flame spreading performance are investigated and this study lays important practical significance to the application of the model on problem solution.

Glans inflation morphology and female cloaca copulatory interactions of the male American alligator phallus†.

The phallic glans of the American alligator (Alligator mississippiensis) is the distal termination of the semen-conducting sulcus spermaticus and during copulation has the closest, most intimate mechanical interactions with the female urodeum, the middle cloacal chamber that contains the opening to the vaginal passages and oviducts. However, the details of this interface leading to insemination and gamete uptake are unclear. Here, we: (1) histologically characterize the underlying tissue types and morphologically quantify the shape changes associated with glans inflation into the copulatory conformation, (2) digitally reconstruct from MRI the 3D shape of functional tissue compartments, and (3) diffusible iodine-based contrast-enhanced computed tomography image the copulatory fit between male phallus and female cloaca. We discuss these results in relation to tissue type material properties, the transfer on intromittent forces, establishing potential copulatory lock, inflated glans volume scaling with body mass/length, the mechanics of semen targeting and insemination, and potential female cryptic choice impacting multiple clutch paternity. In part, this study further clarifies the phallic morphological variation observed among crocodylians and begins to investigate the role(s) these divergent male forms play during copulation interacting with female cloacal forms to increase reproductive success.