Abstract: A membrane filtration system comprising one or more submerged ultrafiltration or microfiltration membrane assemblies at ambient pressure,with mixed liquor is discharged underneath each membrane assembly. In a sequenced batch reactor system, a coarse bubble air diffuser for scouring each membrane assembly is supplied with air only during the backwash cycle of the filtration system and not during the filtration cycle. In a membrane bioreactor system, the biological treatment section is physically separated from the filtration section and fine bubble air diffusion is used in the biological treatment section.

Abstract: A shower arrangement including a plurality of freely movable silver coated decontaminating members in the shower head. Inserts of a decontaminating material such as silver are provided at each end of an upper section of the stand pipe, with the decontaminating members and inserts substantially preventing build up of bacteria.

Abstract: A trash rack for an emergency core cooling system of a nuclear power plant comprises at least one wire-mesh upright screen for filtering debris from coolant flowing in the cooling system. The upright screen is mounted in the coolant flow path with its bottom edge on the floor of an area forming part of the cooling system and a top edge is disposed above the floor at a height less than the level to which the coolant can be expected to rise during a loss of cooling accident. The trash rack also uniquely includes a wire-mesh roof screen that has a downstream edge mated with the top edge of the upright screen and extending upstream thereof to an upstream end spaced from the floor, thereby presenting an unobstructed opening between the floor and the upstream edge of the roof screen.

Abstract: The invention provides a device for dispersing and/or distributing a fluid effluent from a pressurized fluid system. In one embodiment, a device according to the invention includes a hitch member adapted for attachment to a vehicle; a tubular member having at least one discharge opening and at least one attachment port adapted for attachment to a pressurized liquid system; and a diffusing device connected to the at least one discharge opening, the diffusing device having a mesh member including a plurality of openings through which a liquid may be dispersed, wherein at least one of the diffusing device and a portion of the tubular member is adapted to be variously oriented in at least one of the following: a horizontal position and a vertical position.

Abstract: A curb style drain filter kit has a length of flexible filter material of film or mesh with interstices sized to separate small particles from run-off water. The material is wrapped around a conduit which lays in the gutter and fits in a storm sewer inlet. The filter material extends outwardly from the conduit and covers the storm drain grate. An anchor is attached to the outer edge of the material to keep the material flat and covering the grate.

Abstract: An aquarium filtering device includes a body defining an interior divided into a water in-flow chamber and a filter chamber, and a barrier board and two filter panels disposed in the filter chamber. The filter panels have a vertical dimension smaller than the barrier board. The lower edge of the barrier board is spaced from the bottom of the filter chamber by projections formed on the bottom of the filter chamber thereby defining passages into a bio-decomposition section in which bio-filter balls are disposed. Water flowing through the filter panels or alternatively water overflowing the filter panels in case the filter panels are blocked by contaminants, is blocked by the barrier board and guided by the passages into the bio-decomposition section. Tabs are formed on the barrier board to prevent the bio-filter balls from entraining the water flow.

Abstract: Embodiments of the invention provide devices, methods and systems for performing microfluidic chromatography. Particular embodiments provide microfluidic chromatography column devices which can perform chemical separation using small sample volumes and low pressure differentials across the column. One embodiment provides a microfluidic chromatography column device comprising a first, second and third capillary tube. A chromatographic packing is disposed in the second tube with a first and second support layer disposed on opposite ends of the second tube. The support layers are disposed in a substantially flat orientation within the tube. An external coupling joins the tubes such that the tubes are fluidically sealed. The device is configured to have a fluidic resistance such that a pressure differential across the column of less than about 10 psi produces a flow rate through the device of at least about 0.5 ml/min for a liquid solution.

Abstract: This invention relates to a magnetic fluid treatment device comprising at least one fluid channel, the or each fluid channel having at least two peripherally located magnets, the device being adapted to co-operate with a fluid supply conduit, so that, in use, fluid flowing through the fluid channel is subjected to a magnetic field; wherein the at least two magnets are located on opposite sides of the or each fluid channel and have a separation of less than about 90 mm. The invention further relates to a magnetic fluid treatment device comprising at least one fluid channel, the or each fluid channel having at least one peripherally located magnet, wherein the at least one magnet is removably received in a body section of the device.

Abstract: A fluid filter assembly includes a housing having a wall defining an interior, a closed end, and an open end. A filter element is operably oriented in the interior of the housing. A baffle plate is mounted to operably cover the housing open end. The baffle plate includes a first axial face with an exterior top end surface and an outer circumferential wall circumscribing the first axial face. The outer circumferential wall is groove-free and forms an outer radial surface. The outer circumferential wall has a first diameter portion adjacent to the first axial face and a second diameter portion. The second diameter portion is remote from the first axial face. The second diameter portion has a diameter less than the first diameter portion. A seal is located between the housing and the baffle plate resulting from an interference fit between the housing wall and the second diameter portion. A filter arrangement includes the filter assembly operably removably mounted to a filter head.

Abstract: A fluid pollution prevention system for preventing the discharge of hazardous waste from a bilge of a marine vessel. The system includes an locator for positioning a fluid conduit within a bilge. Specifically, the locator is adapted to position an inlet of the fluid conduit within an isolated volume fluid within the bilge that is substantially isolated from petrochemicals floating on the surface of the fluid in the bilge. In one arrangement, the isolated volume is at least partially defined by a floating petrochemical absorber and/or a sidewall that is disposed transverse to a surface of the fluid in the bilge. An outlet of the fluid conduit may be interconnected to a fluid pump that may be located outside the bilge and/or above the fluid within the bilge.

Abstract: A fluid pollution prevention system for preventing the discharge of hazardous waste from a bilge of a marine vessel. The system includes an continuous sidewall that defines a vertically enclosed volume. When positioned within a bilge, the sidewall forms a barrier to petrochemicals floating on a fluid surface within the bilge. An opening near a base of the sidewall permits fluid from beneath the fluid surface to enter the vertically enclosed volume. Such fluid is substantially free of petrochemicals and may be removed form the vertically enclosed volume. Accordingly, by pumping fluid out of the enclosed volume, fluid may be removed form the bilge substantially free of petrochemicals. In one arrangement, the vertically enclosed volume may be sized to receive a bilge pump.

Abstract: A vehicle mountable system adapted to purify contaminated water is provided. The system is supported on a surrounding frame for ease of transport from a storage facility to the bed of a production truck, and all electrical power required for operation of the system is included with the unit. Further, the system provides a heating recirculation feature so that the unit continues to function at temperatures below the freezing point. The system may also be aligned for a closed system, wherein water is taken from a storage tank, pumped into a decontamination enclosure, and recycled back to the storage tank after purification within the system. The system is also provided with a small standby pump to circulate water throughout the system and a plurality of heater elements to keep the system ready for immediate deployment during cold weather.

Abstract: A filtration device having at least one filter packet and a retainer is described. The filter packet includes a membrane having at least a first opening therethrough. The filter packet further includes a retentate screen in fluid communication with the first side of the membrane and a filtrate screen in fluid communication with the second side. The retentate screen includes a permeable material and a seal around an outer perimeter of the permeable material. The permeable material has at least a feed port-defining zone in fluid communication with the first opening. The filtrate screen includes a permeable material and at least a feed port-defining zone in fluid communication with the first opening. The feed port-defining zone of the filtrate screen includes a seal around a perimeter thereof. The filtrate screen has a perimeter open to a filtrate collection area.

Abstract: [Subject] The aim is to provide a separation membrane which can fulfill both high separation capability and high permeation rate. [Solving Means] The disclosed is separation membrane which comprises a porous substrate which is made of ceramic sintered body of which a main ingredient is alumina, and a zeolite membrane which is formed over the surface of the porous substrate, wherein the porous substrate comprises a base layer and a foundation layer which is formed on the base layer and is formed for the zeolite membrane, and the separation membrane is characterized in that a mean pore diameter of the foundation layer is smaller than a mean pore diameter of the base layer.

Abstract: An improved casting substrate is provided for use in a composite membrane for use as a fluid filtration medium. The composite membrane has good adhesion between the casting substrate and the microporous membrane while maintaining high permeability. The casting substrate comprises a single spunbond layer or a multiple spunbond layers formed of thermoplastic fibers, optionally comprising at least one meltblown layer. The casting substrate allows the membrane casting solution to penetrate the casting substrate uniformly to a controlled depth without penetrating through the entire thickness of the substrate. The casting substrate has good uniformity of mean pore size, basis weight, thickness and surface roughness.

Abstract: A separation device for the separation of constituents of different density, in particular of a fluid fed from a well hole, exhibits a container in which the fluid at least partially after entry via a feed line is separated into its constituents using centrifugal force in the radial direction and/or using gravitational force in the vertical direction. To improve this type of separation device such that it can be constructed more compact and in a constructively more simple manner and also that it simultaneously can reliably enable separation of all constituents and their removal from the separation device, a classifier device is arranged in a lower section of the container interior, which at least exhibits one discharge line, extending radially outwards, for the discharge of the fluid into the container interior and delivery lines, joined to the container interior at different levels in the vertical direction, for the separated fluid constituents.

Abstract: The invention relates to a scraper, which comprises an elongated, at least tension transmitting flexible structure, which is formed of formed pieces (X), being coupled with each other one after the other in a longitudinal direction (s) and that are arranged to twist (w1) in respect with each other round an axis standing in a direction of height (h) by means of a joint arrangement (N), whereby the joint arrangement (N) comprises edge projections (N1), existing in a preceding formed piece one below the other in the direction of height (h) of the formed piece, and a cental projection (N2) existing in the following formed piece and that is to be placed between the above edge projections. A joint arrangement (N; N?) is arranged to enable twisting (w2) of the successive formed pieces (X) in respect with each other round an essentially longitudinal axis (s).

Abstract: A density baffle assembly for use in a water treatment system is disclosed. The density baffle assembly includes a plurality of density baffles where each density baffle comprises a corrugated panel member having an upper edge, a lower edge, a first lateral side, and a second lateral side, with a corrugated pattern running across the corrugated panel member. Each density baffle also comprises a support flange integrally connected to the upper edge of the corrugated panel member. The support flange may be affixed to a wall of the water treatment system using a fastening means. Adjacent corrugated panel members may be nested together at their lateral sides and secured to each other using a fastening means.

Abstract: Radionuclide can be easily removed from a solution under aerobic condition by culturing Euglena in contact with radionuclide in a solution that is suitable for viability Euglena to thus transfer said radionuclide to Euglena and separating said Euglena comprising radionuclide from said solution.

Abstract: A process for storing entrapping immobilization pellets in which microorganisms are entrapped and immobilized in an immobilizing material until the entrapping immobilization pellets are used in a treatment tank, the process comprising: storing a large pellet block in water at 15° C. or less or in air at a relative humidity of 90% or more and a temperature of 15° C. or less until the pellet block is cut into the entrapping immobilization pellets and used.

Abstract: This invention is directed to a wastewater treatment system having a fluidizable media carrying anoxic bacteria in a first treatment zone and a filter membrane positioned in a second treatment zone. A wastewater is contacted with the fluidizable media and further contacted with air and a filter membrane.

Abstract: In a waste water treatment apparatus and/or method, waste water containing aminoethanol and dimethyl sulfoxide is introduced into a first denitrification tank within a first waste water treatment apparatus. Malodorous gas generated in the first waste water treatment apparatus is decomposed and treated in a second waste water treatment apparatus where another waste water is treated as another system. The second waste water treatment apparatus has a second nitrification tank including a semi-anaerobic section. The malodorous gas is introduced from the first waste water treatment apparatus into a scrubber. The malodorous gas is treated by sludge which is circulated between the second nitrification tank and the scrubber.

Abstract: A method of controlling duration of a backwash cycle of a filtration system commences with initiating pumping of a backwash fluid (12) through a filter (6) of the filtration system by way of a backwash pump (17). The flow rate of backwash fluid (12) is maintained to within 20% of a predetermined flow rate. A pressure sensor (23) takes a pressure measurement indicative of a pressure differential between upstream and downstream sides of the filter (6). Changes in the pressure measurement over time are monitored. A backwash duration controller (18) stops the backwash pump (17) when a rate of change of the pressure measurement reaches a predetermined minimum value.

Abstract: The invention relates to systems and methods of treating water by directing the water to a first reverse osmosis (RO) membrane; separating the water using the first RO membrane; adding a chelating agent to first permeate and/or raising the pH of the first permeate to between about 5.5 and 7.5 before a second RO membrane; and separating the first permeate into a second permeate and a second concentrate using the second RO membrane, thereby separating constituents from the water.

Abstract: Systems and methods for removing lipids from a fluid, such as plasma, or from lipid-containing organisms. A fluid is combined with at least one extraction solvent, which causes the lipids to separate from the fluid or from lipid-containing organisms. The separated lipids are removed from the fluid. The extraction solvent is removed from the fluid or at least reduced to an acceptable concentration enabling the delipidated fluid to be administered to a patient without the patient experiencing undesirable consequences. Once the fluid has been processed, the fluid may be administered to a patient who donated the fluid, to a different patient, or stored for later use.

Abstract: A method and system (10) for selectively removing one component of a material thereby concentrating other components of the material are disclosed. The material is cooled to below the melting temperature of the material to form a supercooled liquid phase with heat transfer plate with cooling channels (20). Ultrasonic energy from ultrasonic drivers (42) is applied to the material to form solid phase crystals of the component to be removed. These crystals are removed to leave the concentrated product. The ultrasonic energy prevents the growth of dendrites on the crystals, resulting in the formation and removal of small crystals of the component to be removed without damage to or removal of the remaining components. Methods and apparatuses for cryoprecipitation and chromatography are also disclosed.

Abstract: Systems and methods for treating water as well as maintaining water treatment systems are disclosed. The systems and methods include circulating influent water in a recirculation loop. In addition, a contaminate level may be monitored by sensors. When the contaminate level exceeds a set contaminate level, contaminates may be bleed from the systems.

Abstract: The present invention provides a preanalysis treatment method for nitropolycyclic aromatic hydrocarbons present in diesel engine exhaust particulates and the like. The method comprises feeding a test solution 160 in which a sample containing polycyclic aromatic hydrocarbons is dissolved in a solvent to a silica gel column 170 using an eluent lowest in polarity among a plurality of eluents 110, 120 and 130 to be a mobile phase for the test solution unlike the solvent and to differ in polarity from each other; and then allowing polar solvents to flow in ascending order of polarity to fractionate nitropolycyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons other than the nitropolycyclic aromatic hydrocarbons.

Abstract: A method of operating chromatography column apparatus comprising a column tube (101) and first and second discrete end cell structures, associated with the respective ends of the column tube and positionable to close off the column tube and define therein a column space for retaining chromatography medium in use of the apparatus. The first end cell portion comprises a piston portion (106) fitting slidably in the column tube. The column tube and the second end cell structure are separated to provide an access spacing between them. The piston portion (106) of the first end cell structure is advanced through the column tube to expose it at the open second end of the column tube, for maintenance of the piston portion thus exposed. Corresponding chromatography apparatus is another aspect of the disclosure.

Abstract: Device for recovering a material to be measured comprising a reservoir filled with a sample holding material impregnated with a sample liquid in which a material to be measured is dissolved and an adsorbing column for adsorbing the material to be measured, wherein the reservoir and the adsorbing column are communicated by a straight pipe, and further communicated with a recovery vessel via a recovery pipe branched out the straight pipe. Accordingly, operations of opening/closing or switching a first valve provided on the in-flow side of the reservoir, a second valve provided on the out-flow side of the adsorbing column, and a third valve provided to a vent hole to the atmosphere in the recovery vessel, make it possible to recover the material to be measured without depositing the material on the valves.

Abstract: The application describes apparatus and methods using ultrasound transmitted through a chromatography column bed to determine the status of materials in the bed space, particularly during chromatography runs. Detected conditions include the profile of a band of eluting material—to see whether it is satisfactory—the arrival of a band of material at the column output, the fitness for use of the ed packing, the passage of different mobile phases, e.g. salt fronts, and other conditions. Aspects claimed include control processors and corresponding programmed products.

Abstract: A method of reclaiming a well completion brine solution containing metal impurities by introducing to the brine solution an organic chelant of the formula: and may be either a neutral compound, a corresponding salt, or a corresponding quaternary salt, wherein: D is F—A (Y3)u(Y4)v; R is independently selected from Cp or CpC(O); Cp is a C1-C36, preferably a C8-C36, hydrocarbyl group, optionally substituted with one or more substituents selected the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups; each A is independently selected from —N and —P; Y1 is independently selected from J, —[(F)—A(J)]w Y6 and R; J, R1, Y2, Y3, Y4, Y5 and Y6 are independently selected from the group consisting of —H, R, —(F)nCO2Z and —(CH2)nPO(OZ)2; each F is independently selected from a C1-C12 hydrocarbyl group, optionally substituted with one or more substituents selected from the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups; Z is —H, a balanced organic

Abstract: A composition comprising a magnesium halide coated macroporous carbonaceous substrate is provided for effecting moisture removal from a hydrogen halide fluid. Moisture removal is effected by intimately contacting the hydrogen halide fluid with the magnesium halide coated macroporous carbonaceous substrate and separating the fluid from the coated substrate.

Abstract: Methods and apparatus are disclosed for recovering magnetically attractable wellbore casing fragments from drilling fluid used in hydrocarbon-producing formations.

Abstract: A method and device for protecting an aqueous system from scale precipitation by depressing scale precipitation in a bulk phase of a water supply, the device including: (a) an electrolytic cell for fluidly connecting to the system, including: (i) a tank for receiving the water supply, the tank having a copper surface forming a cathode of the cell; and (ii) an element having a zinc surface disposed within the tank, and forming an anode of the cell; (b) a controlling unit for controlling a current (I) from the power supply; and (c) a flowmeter for measuring a flow rate of the water supply, the flow rate associated with a flow rate of water into the system, wherein the controlling unit is designed to control the current according to the flow rate so as to depress the scale precipitation in the bulk phase of the water supply, and wherein the current I exceeds (1.84?A)*Q and is less than (1.84+A)*Q, wherein I is measured in amperes; Q is the total flow rate (m3/h); and A is a positive number and less than 1.05.

Abstract: An object of the present invention is to provide a process for easily producing a water-soluble polymer which has a reduced residual monomer amount and has excellent various flocculating performances when used as a flocculant, the process being capable of grafting a high molecular weight polymer onto starch. A process for producing a water-soluble polymer is provided, which comprises polymerizing water-soluble radical-polymerizable monomers comprising a cationic radical-polymerizable monomer as an essential component in a presence of a polysaccharide, an azo polymerization initiator, and a hydrogen-abstracting agent. A polymer flocculant is also provided, which comprises a water-soluble polymer obtained by the production process.

Abstract: The invention relates to a method for the accelerated dehydration of sludges in sludge disposal areas, especially of sludges from rivers and harbors, by the exclusive use of anionic polymer flocculants and the use of materials obtained according to the inventive method.

Abstract: Disclosed is a method for photolyzing organic matters by which various organic matters including harmful organic matters can be photolyzed quickly. Also disclosed is an efficient method for treating wastewater which utilizes the photolyzing method. An organic matter is photolyzed in a reaction system containing a photocatalyst and a hydrophobic ionic liquid represented by the formula (2) below. [In the formula, Me represents a methyl group and Et represents an ethyl group.

Abstract: A method and apparatus are provided for the controlled application of ultrasonic energy for conditioning of mixtures of gas and liquids by evolving and/or agglomerating gas bubbles existing with or in a liquid or for coalescing droplets of liquid dispersed in another liquid. The invention in preferred embodiments thereof comprises a coalescing apparatus for Increasing the droplet size of a mixture formed as a liquid dispersed in another liquid, and a de-gassing apparatus arranged to evolve and/or agglomerate gaseous bubbles in a gas/liquid mixture. In the apparatuses, ultrasonic transducers are used to impart vibrational energy to the mixtures.

Abstract: An improved method of treating a body of salt water containing chloride ion in which the level of chlorine in the water is controlled by an electrochemical chlorine generator wherein the improvement comprises increasing the chlorine generation in the water without increasing the generator output by addition of a composition comprising potassium monopersulfate is disclosed.

Abstract: Ammonium perfluorooctanoate—also called APFO, PFOA or C8—is a surfactant associated with the production of Teflon®, and is also present in products such as fire-fighting foams and may be formed from the microbial degradation of grease-resistant coatings applied to items such as pizza boxes. APFO itself does not hydrolyze, photolyze, or biodegrade under environmental conditions and is biologically additive. A process by which APFO may be removed and recovered from water by electrosorption is discovered. Removal and recovery by electrosorption form an inexpensive and environmentally friendly method of removal and recovery of APFO.

Abstract: A bicycle holder and/or bicycle stand has a supporting foot and a holding mechanism situated thereon for two tubes of a bicycle frame, wherein the supporting foot has a base part and a shaft, the base part is embodied so that it is possible for the supporting foot to be placed onto it or mounted to a wall or ceiling by means of the base part; and the shaft is embodied so that when the supporting foot is wall-mounted, the shaft is able to support a frame component of at least one bicycle in a nonslip fashion.

Abstract: A wheel rotation device assists in cleaning, inspection and maintenance of wheels. The device has a ramp, a backstop, and two contoured rollers, fastened to rails. The device operates upon a flat surface such as a garage floor or driveway, and avoids slipping from friction with the flat surface and a non-skid treatment on to the underside of the rails. The ramp allows the motorcycle to be rolled forward onto the rollers that centers the motorcycle wheel upon and between the rollers as it is manually rotated. The backstop limits forward movement of the motorcycle wheel to within the rear of the device. The rear roller, nearest the backstop, has spindles projecting through the rails and have machined ends that accept a tool to rotate the motorcycle wheel.

Abstract: An angled rack for supporting footwear includes a plurality of angled brackets securable with conventional fasteners to a vertical wall or door. Each of the angled brackets define a plurality of apertures therethrough which cooperate and support a corresponding plurality of elongated cylindrical rods. The rods pass through the apertures formed in the brackets to provide a supporting platform or footwear or the like. The angled disposition of the brackets and the resulting angled disposition of cylindrical rods provides a convenient stable surface for footwear to rest upon.

Abstract: Disclosed is an improved shelf tray assembly for use to hold and move forward in a simple and efficient way articles of a given dimension placed on a shelf toward a front edge of this shelf in order to allow frontal display of these articles. This assembly has a front rail installable on the shelf close to its front edge, a rear rail installable onto the shelf in parallel relationship with respect to the front rail and one or more tracks snappable onto the front and rear rails, each track acting as a support for the articles to be displayed and having a guiding rail on which a pushing element is slideably mounted. Advantageously, one or more clips are provided at the front end of each track to rigidly retain this track to the front rail. Advantageously also, each track has several slots made in its upper surface to receive one or more lateral partitions so as to guide the articles to be displayed when they are pulled forward, whatever their size.

Abstract: A holding apparatus for a fastener (40) includes a board (10) and a holding member (30). The board defines at least one hole (12) for receiving the fastener. The holding member is attached to the board. At least one resilient arm (34) is formed on the holding member adjacent to the at least one hole for supporting the fastener.

Abstract: An adjustable shelving assembly and a support structure for supporting the adjustable shelf assembly. The adjustable shelf assembly may include at least one extension shelf unit, slidably oriented with respect to a central shelf unit such that the width and/or depth of the shelf may be adjusted. The adjustable shelf assembly may be adjusted without removing the shelf from the accompanying support structure or causing the central shelf unit to be moved. The adjustable shelf assembly may also include structure for receiving advertisements, product identifiers or the like.

Abstract: The inventive counter display for articles such as perfumes and cosmetic products comprises a connecting element (3) extending between a lower end (3b) fixed to a displaying element (2) and a top end (3a) pivotally mounted with respect to a ceiling (8).

Abstract: A product display hanger includes a substrate with an adhesive applied to one surface. A release liner is disposed on the substrate and may include two substantially parallel die cuts formed therein. Thus, a portion or all of the release liner between the die cuts can be separated from the substrate to expose the adhesive on the substrate. Portions of the release liner remaining on the substrate have indicia thereon for identifying the preferred alignment and spacing for products to be displayed or other visible indicia or holes may be provided as a means of guidance for mounting product. At least one hanger hole may be formed near one end of the display hanger for suspending the display hanger from a hook.

Abstract: A collapsible clothes drying rack is disclosed herein. An embodiment of the collapsible drying rack has a first frame member that is collapsible between a folded position and an extended position. The first frame member may have a first locking arm engaged thereto. The embodiment may also have a plurality of rods, wherein each rod may be of equal length. Each rod may have a first end and a second end, and the first end of each rod may be selectively engaged to either the first frame member or the first locking arm. The embodiment may also have a second frame member collapsible between a folded position and an extended position. The second frame member may have a second locking arm engaged thereto. The second end of each of rod may be selectively engaged to either the second frame member or the second locking arm.