Abstract: Disclosed is a guard for a trailer that utilizes a strap webbing to prevent a vehicle from underriding the trailer. The guard includes one or more straps that span the length of the trailer and may include additional structures to pre-tension the straps before a crash or supplement the tension of the straps as a vehicle crashes into the guard. When two or more straps are utilized on a single guard, the straps may be aligned parallel to each other or may form a cross shape. Additional structures may be incorporated into the guard to direct an impacting vehicle towards or away from specific features of the trailer.

Abstract: Disclosed is a guard for a trailer that utilizes a strap webbing to prevent a vehicle from underriding the trailer. The guard includes one or more straps that span the length of the trailer and may include additional structures to pre-tension the straps before a crash or supplement the tension of the straps as a vehicle crashes into the guard. When two or more straps are utilized on a single guard, the straps may be aligned parallel to each other or may form a cross shape. Additional structures may be incorporated into the guard to direct an impacting vehicle towards or away from specific features of the trailer.

Abstract: The present invention relates to a method for synthesis of o-diphenylphosphinobenzoic acid which includes the steps as follows: using chlorodiphenylphosphine as starting material, chlorodiphenylphosphine and alkali metal are added to the solvent to conduct cracking, which produces a diphenyl phosphine alkali metal salt, then o-chlorobenzoic acid salt or o-chlorobenzoic acid ester is added to conduct coupling reaction to produce diphenylphosphinobenzoic acid salt or diphenylphosphinobenzoic acid ester, o-diphenylphosphinobenzoic acid is obtained after hydrolysis. o-diphenylphosphinobenzoic acid can be prepared under atmospheric pressure at temperature above 0° C. by using the present method. The method is safe and stable to operate and can save a lot of energy, thus being suitable for large-scale production.